// Package bash provides utilities for executing bash commands and processing their output.
// It includes functionality for process management, system monitoring, and output formatting.
package bash

import (
        "bytes"
        "errors"
        "fmt"
        "os/exec"
        "regexp"
        "strconv"
        "strings"
)

const (
        // ansi is a regular expression pattern for matching ANSI escape sequences.
        // These sequences are used for terminal color formatting and control.
        // The pattern matches:
        // - CSI (Control Sequence Introducer) sequences starting with ESC[
        // - OSC (Operating System Command) sequences
        // - Other common terminal control sequences.
        ansi = "[\u001B\u009B][[\\]()#;?]*(?:(?:(?:[a-zA-Z\\d]*(?:;[a-zA-Z\\d]*)*)?\u0007)|(?:(?:\\d{1,4}(?:;\\d{0,4})*)?[\\dA-PRZcf-ntqry=><~]))" //nolint:lll

        // commandBash specifies the default command to use for bash shell execution.
        commandBash = "bash"

        // zeroValue is the default string value returned when numeric operations fail.
        zeroValue = "0.0"

        // uptimeZeroValue is the default string value returned when uptime cannot be determined.
        uptimeZeroValue = "00:00:00"
)

// ansiRegexp is a precompiled regular expression created from the ansi pattern.
// This is used for efficient stripping of ANSI escape sequences from strings.
var ansiRegexp = regexp.MustCompile(ansi)

// Common error definitions used throughout the package.
var (
        // ErrInvalidCommand indicates that command is invalid.
        ErrInvalidCommand = errors.New("invalid command")

        // ErrEmptyPID indicates that a process lookup returned an empty process ID.
        ErrEmptyPID = errors.New("empty process id")

        // ErrNotRunning indicates that the requested process is not currently running.
        ErrNotRunning = errors.New("process is not running")

        // ErrBashExecuteFailed indicates that a bash command execution failed.
        ErrBashExecuteFailed = errors.New("bash execute failed")
)

// Strip removes all ANSI escape sequences and trailing newline characters from a string.
// This is useful for cleaning up colored terminal output or formatted text.
//
// Parameters:
//   - str: The input string potentially containing ANSI codes
//
// Returns:
//   - A cleaned string with all ANSI sequences and trailing newlines removed
//
// Example:
//
//        cleaned := Strip("\033[32mHello\033[0m\n") // Returns "Hello".
func Strip(str string) string {
        return strings.TrimRight(ansiRegexp.ReplaceAllString(str, ""), "\n")
}

// Execute runs a system command and captures its output streams.
// It provides a convenient wrapper around exec.Command with integrated error handling.
//
// Parameters:
//   - name: The name/path of the command to execute (e.g. "ls", "/bin/bash")
//   - args: Variadic arguments to pass to the command (e.g. "-l", "-a")
//
// Returns:
//   - string: The combined stdout output of the command
//   - error:  Returns ErrBashExecuteFailed if stderr contains output,
//     or the original exec error if the command failed to run.
//     Returns nil if execution was successful with empty stderr.
//
// Behavior:
//   - Captures both stdout and stderr streams separately
//   - Considers any stderr output as an error condition
//   - Preserves the command's exit status error if present
//   - Trims no output - returned strings may contain trailing newlines
//
// Example:
//
//        output, err := Execute("ls", "-l", "/tmp")
//        if err != nil {
//            // Handle error (either from stderr or command failure)
//        }
//        fmt.Println(output)
//
// Notes:
//   - For bash commands, consider using commandBash constant as name
//   - Command output is not stripped of ANSI codes (use Strip() separately)
//   - Not suitable for interactive commands requiring stdin.
func Execute(name string, args ...string) (string, error) {
        var stdout, stder bytes.Buffer

        cmd := exec.Command(name, args...)

        cmd.Stdout = &stdout
        cmd.Stderr = &stder

        err := cmd.Run()

        // Return stderr if present, even if command technically succeeded.
        if stder.String() != "" {
                return stdout.String(), fmt.Errorf("%w: %s", ErrBashExecuteFailed, stder.String())
        }

        return stdout.String(), err
}

// GetLargeFileList finds large files with specific extension in given path
// Parameters:
//   - path: directory to search
//   - ext: file extension to match (e.g. ".log")
//   - params: optional count parameter (default 20)
//
// Returns list of files or error if command fails.
func GetLargeFileList(path, mask string, params ...int) (string, error) {
        count := "20"
        if len(params) > 0 {
                count = strconv.Itoa(params[0])
        }

        args := []string{
                "-c", "ls " + path + " -hSRs | egrep '" + mask + "' | head -" + count,
        }

        return Execute(commandBash, args...)
}

// PidofByProcess retrieves the process ID (PID) of a running process by its name.
// It uses the system's 'pidof' command to find the PID of the specified process.
//
// Parameters:
//   - process: Name of the process to look up (e.g., "nginx", "java").
//     Should match the exact executable name.
//
// Returns:
//   - string: The PID of the process as a string if found.
//   - error:  May return:
//   - Original error from command execution if pidof fails
//   - ErrEmptyPID if process is not running or pidof returns empty
//   - Other system errors if command cannot be executed
//
// Behavior:
//   - Executes 'pidof <process>' command internally
//   - Automatically trims trailing newline from output
//   - Returns first PID if multiple instances are running (pidof behavior)
//   - Does not validate if the process is actually running beyond PID existence
//
// Example:
//
//        pid, err := PidofByProcess("nginx")
//        if err != nil {
//            if errors.Is(err, ErrEmptyPID) {
//                fmt.Println("Nginx is not running")
//            } else {
//                log.Fatalf("Error checking nginx: %v", err)
//            }
//        }
//        fmt.Printf("Nginx PID: %s\n", pid)
//
// Notes:
//   - Requires pidof command to be available in system PATH
//   - For more advanced process lookups, see PidofByProcessAndParam
//   - Returned PID string may need conversion to int for numeric operations
//   - On systems with multiple process instances, consider using pgrep instead.
func PidofByProcess(process string) (string, error) {
        out, err := Execute("pidof", process)
        if err != nil {
                return "", err
        }

        if l := strings.Split(out, "\n"); len(l) > 0 {
                pid := l[0]
                if pid == "" {
                        return "", ErrEmptyPID
                }

                return pid, nil
        }

        return "", ErrNotRunning
}

// PidofByProcessAndParam finds a process ID by process name and matching parameter.
// It executes a command pipeline: pgrep -af <process> | grep <param> to locate
// the specific process instance containing the given parameter.
//
// Parameters:
//   - process: The name of the process to search for (e.g. "java", "nginx")
//   - param: The parameter string to match in the process command line
//     (e.g. "--config=myapp.conf", "servername")
//
// Returns:
//   - string: The PID of the matching process
//   - error: ErrEmptyPID if process is found but PID is empty,
//     ErrNotRunning if no matching process is found,
//     or other errors from command execution
//
// Example:
//
//        pid, err := PidofByProcessAndParam("java", "-Dapp.name=myapp")
//        if err != nil {
//            // handle error
//        }.
func PidofByProcessAndParam(process, param string) (string, error) {
        if process == "" || param == "" || string(process[0]) == "-" {
                return "", ErrInvalidCommand
        }

        if string(param[0]) == "-" {
                param = "\\" + param
        }

        cmd := fmt.Sprintf("pgrep -af %q | grep -v %q | grep %q | grep -o -e %q", process, " bash ", param, `^[0-9]*`)

        out, err := Execute(commandBash, "-c", cmd)
        if err != nil {
                return "", err
        }

        if l := strings.Split(out, "\n"); len(l) > 0 {
                pid := l[0]
                if pid == "" {
                        return "", ErrEmptyPID
                }

                return pid, nil
        }

        return "", ErrNotRunning
}

// GetUptimeByPID retrieves the elapsed time since a process started using its PID.
// It executes the 'ps' command to get the process's running duration in format [[DD-]HH:]MM:SS.
//
// Parameters:
//   - pid: The process ID as a string (e.g., "12345"). Must be a valid running process ID.
//
// Returns:
//   - string: The process uptime in format:
//   - "MM:SS" for processes running <1 hour
//   - "HH:MM:SS" for processes running <1 day
//   - "DD-HH:MM:SS" for processes running multiple days
//   - uptimeZeroValue ("00:00:00") if the process is not found
//   - error:  Returns:
//   - Original error if 'ps' command execution fails
//   - nil if successful (even if process not found)
//
// Behavior:
//   - Uses 'ps -o etime= -p PID' command to get process duration
//   - Automatically trims whitespace and newlines from output
//   - Returns zero value (not error) if process doesn't exist
//   - Output format matches system 'ps' command behavior
//
// Example:
//
//        uptime, err := GetUptimeByPID("12345")
//        if err != nil {
//            log.Printf("Failed to check uptime: %v", err)
//        }
//        fmt.Printf("Process running for: %s", uptime) // e.g. "01:23:45"
//
// Notes:
//   - Requires 'ps' command to be available in system PATH
//   - Unlike other functions, returns zero value rather than error for missing process
//   - For empty/zero uptime, check against uptimeZeroValue constant
//   - Uptime resolution is seconds (no milliseconds).
func GetUptimeByPID(pid string) (string, error) {
        uptime, err := Execute("ps", "-o", "etime=", "-p", pid)
        if err != nil {
                return uptimeZeroValue, err
        }

        return strings.Trim(uptime, " \n"), nil
}

// CPUPercentByPID retrieves the CPU usage percentage for a specific process.
// The percentage represents the process's total CPU utilization since its start.
//
// Parameters:
//   - pid: The process ID as a string (e.g., "1234"). Must be a valid running process.
//
// Returns:
//   - string: CPU usage percentage with "%" suffix (e.g., "25.5%")
//     Returns zeroValue + "%" ("0.0%") if:
//   - Process is not found
//   - Process is using 0% CPU
//   - Command fails
//   - error:  Error from command execution if ps command fails,
//     nil if successful (even if process shows 0% usage)
//
// Behavior:
//   - Uses 'ps S -p PID -o pcpu=' command to get CPU percentage
//   - The 'S' option includes child processes in calculation
//   - Automatically trims whitespace and appends "%" symbol
//   - Returns string formatted to one decimal place
//
// Example:
//
//        cpu, err := CPUPercentByPID("1234")
//        if err != nil {
//            log.Printf("CPU check failed: %v", err)
//        }
//        fmt.Printf("CPU Usage: %s", cpu) // e.g. "75.3%"
//
// Notes:
//   - CPU percentage is relative to a single core (may exceed 100% on multicore systems)
//   - Requires 'ps' command to be available in system PATH
//   - For containerized processes, results may differ from host metrics
//   - Values are snapshots, not averages over time
//   - Consider using multiple samples for monitoring trending usage.
func CPUPercentByPID(pid string) (string, error) {
        cpu, err := Execute("ps", "S", "-p", pid, "-o", "pcpu=")
        if err != nil {
                return zeroValue + "%", err
        }

        return strings.Trim(cpu, " \n") + "%", nil
}

// MemPercentByPID retrieves the memory usage percentage for a specific process.
// The percentage represents the process's resident memory relative to total system memory.
//
// Parameters:
//   - pid: The process ID as a string (e.g., "5678"). Must be a valid running process.
//
// Returns:
//   - string: Memory usage percentage with "%" suffix (e.g., "4.2%")
//     Returns zeroValue + "%" ("0.0%") if:
//   - Process is not found
//   - Process uses 0% memory
//   - Command execution fails
//   - error:  Error from command execution if ps command fails,
//     nil if successful (even if process shows 0% usage)
//
// Behavior:
//   - Uses 'ps S -p PID -o pmem=' command to get memory percentage
//   - The 'S' option includes child processes in calculation
//   - Automatically trims whitespace and appends "%" symbol
//   - Returns string formatted to one decimal place
//
// Example:
//
//        mem, err := MemPercentByPID("5678")
//        if err != nil {
//            log.Printf("Memory check failed: %v", err)
//        }
//        fmt.Printf("Memory Usage: %s", mem) // e.g. "2.8%"
//
// Notes:
//   - Percentage is relative to total physical memory (RAM)
//   - Does not include shared memory or swap usage
//   - Requires 'ps' command to be available in system PATH
//   - Values represent current snapshot, not averages over time.
func MemPercentByPID(pid string) (string, error) {
        mem, err := Execute("ps", "S", "-p", pid, "-o", "pmem=")
        if err != nil {
                return zeroValue + "%", err
        }

        return strings.Trim(mem, " \n") + "%", nil
}

// MemUsedByPID calculates the total resident memory usage of a process and its children in megabytes.
// It sums the RSS (Resident Set Size) memory of all process threads and converts to MB.
//
// Parameters:
//   - pid: The process ID as a string (e.g., "1234"). Must be a valid running process.
//
// Returns:
//   - string: Memory usage formatted with " MB" suffix (e.g., "24.5 MB")
//     Returns zeroValue + " MB" ("0.0 MB") if:
//   - Process is not found
//   - Process uses no resident memory
//   - Command execution fails
//   - error:  Error from command execution if the bash command fails,
//     nil if successful (even if memory usage is 0)
//
// Implementation Details:
//   - Uses bash command pipeline:
//     1. `ps -ylp PID` lists all threads with memory info
//     2. `awk` sums the RSS (column 8) and converts to MB (/1024)
//   - Automatically trims whitespace/newlines from output
//   - Adds " MB" suffix to clarify units
//
// Example:
//
//        memUsage, err := MemUsedByPID("1234")
//        if err != nil {
//            log.Printf("Memory check failed: %v", err)
//        }
//        fmt.Printf("Memory used: %s", memUsage) // e.g. "45.2 MB"
//
// Notes:
//   - Measures physical RAM usage (RSS), not virtual memory
//   - Includes memory used by all process threads
//   - Values are in binary megabytes (MiB, 1024-based)
//   - Requires GNU ps and awk utilities.
func MemUsedByPID(pid string) (string, error) {
        args := []string{
                "-c", "ps -ylp " + pid + " | awk '{x += $8} END {print \"\" x/1024;}'",
        }

        mem, err := Execute(commandBash, args...)
        if err != nil {
                return zeroValue + " MB", err
        }

        return strings.Trim(mem, " \n") + " MB", nil
}

// MemUsed retrieves the total used system memory in megabytes (MB).
// It calculates the actively used memory excluding buffers/cache.
//
// Returns:
//   - string: Total used memory formatted with " MB" suffix (e.g., "2048 MB")
//     Returns zeroValue + " MB" ("0.0 MB") if:
//   - Command execution fails
//   - Unable to parse memory information
//   - error:  Error from command execution if the bash command fails,
//     nil if successful
//
// Implementation Details:
//   - Uses bash command pipeline:
//     1. `free` command to get memory statistics
//     2. `awk` extracts the used memory value (column 3 from second line)
//     3. Converts from kilobytes to megabytes (/1024)
//     4. Formats as integer (%.0f) to remove decimal places
//   - Automatically trims whitespace/newlines from output
//   - Adds " MB" suffix to clarify units
//
// Example:
//
//        usedMem, err := MemUsed()
//        if err != nil {
//            log.Printf("Failed to get system memory: %v", err)
//        }
//        fmt.Printf("System memory used: %s", usedMem) // e.g. "3752 MB"
//
// Notes:
//   - Measures actual used memory excluding buffers/cache
//   - Values are in binary megabytes (MiB, 1024-based)
//   - Requires GNU free and awk utilities
//   - Represents system-wide memory usage, not per-process
//   - Consider using /proc/meminfo for more detailed breakdown.
func MemUsed() (string, error) {
        args := []string{
                "-c", "free | awk 'NR==2 { printf(\"%.0f\", $3/1024); }'",
        }

        mem, err := Execute(commandBash, args...)
        if err != nil {
                return zeroValue + " MB", err
        }

        return strings.Trim(mem, " \n") + " MB", nil
}

// MemAvail retrieves the total available system memory in megabytes (MB).
// This represents the physical RAM available for new processes, excluding buffers/cache.
//
// Returns:
//   - string: Total available memory formatted with " MB" suffix (e.g., "8192 MB")
//     Returns zeroValue + " MB" ("0.0 MB") if:
//   - Command execution fails
//   - Unable to parse memory information
//   - error:  Error from command execution if the bash command fails,
//     nil if successful
//
// Implementation Details:
//   - Uses bash command pipeline:
//     1. `free` command to get memory statistics
//     2. `awk` extracts the total memory value (column 2 from second line)
//     3. Converts from kilobytes to megabytes (/1024)
//     4. Formats as integer (%.0f) for clean output
//   - Automatically trims whitespace/newlines from output
//   - Adds " MB" suffix to clarify units
//
// Example:
//
//        availMem, err := MemAvail()
//        if err != nil {
//            log.Printf("Failed to get available memory: %v", err)
//        }
//        fmt.Printf("Available system memory: %s", availMem) // e.g. "16384 MB"
//
// Notes:
//   - Measures physical RAM, not including swap space
//   - Values are in binary megabytes (MiB, 1024-based)
//   - Requires GNU free and awk utilities
//   - Represents system-wide available memory
//   - For accurate container memory limits, check cgroup settings.
func MemAvail() (string, error) {
        args := []string{
                "-c", "free | awk 'NR==2 { printf(\"%.0f\", $2/1024); }'",
        }

        mem, err := Execute(commandBash, args...)
        if err != nil {
                return zeroValue + " MB", err
        }

        return strings.Trim(mem, " \n") + " MB", nil
}

package extract

// String safely dereferences a string pointer, returning the string value or empty string if nil.
// This provides a nil-safe way to access string pointers and ensures you always get a valid string:
//   - If pointer is non-nil: returns the underlying string value
//   - If pointer is nil: returns an empty string ("")
//
// Useful when working with optional string fields in structs or API responses.
func String(pointer *string) string {
        if pointer != nil {
                return *pointer
        }

        return ""
}

// IsEmptyString checks if a string pointer is nil or points to an empty string.
// Returns true if either:
//   - The pointer is nil
//   - The dereferenced string is empty ("")
//
// Useful for safely checking optional string fields that may be nil.
func IsEmptyString(pointer *string) bool {
        return pointer == nil || *pointer == ""
}

// Int64 safely dereferences an int64 pointer, returning the value or 0 if nil.
//
// This helper function provides nil-safety when working with optional numeric fields:
//   - If pointer is non-nil: returns the underlying int64 value
//   - If pointer is nil: returns 0 (zero value for int64)
//
// Useful when working with optional int64 fields in structs or API responses.
func Int64(pointer *int64) int64 {
        if pointer != nil {
                return *pointer
        }

        return 0
}

package files

import (
        "fmt"
        "io"
        "os"
        "path/filepath"
        "strings"
        "syscall"
        "time"
)

// OwnerWritePerm provides 0755 permission.
const OwnerWritePerm = os.FileMode(0o755)

// FileExists checks if a file exists and is not a directory before we
// try using it to prevent further errors.
func FileExists(filename string) bool {
        info, err := os.Stat(filename)
        if os.IsNotExist(err) {
                return false
        }

        return !info.IsDir()
}

// FileCopy copies src file to destination path.
func FileCopy(src string, destination string, perms ...os.FileMode) error {
        perm := os.ModePerm
        if len(perms) != 0 {
                perm = perms[0]
        }

        input, err := os.ReadFile(src)
        if err != nil {
                return err
        }

        return os.WriteFile(destination, input, perm)
}

// ReadStringFile reads file as string.
func ReadStringFile(path string, name string) (string, error) {
        b, err := os.ReadFile(path + "/" + name)
        if err != nil {
                return "", err
        }

        return string(b), nil
}

// ReadBinFile reads file as slice of bytes.
func ReadBinFile(path string, name string) ([]byte, error) {
        b, err := os.ReadFile(path + "/" + name)
        if err != nil {
                return []byte{}, err
        }

        return b, nil
}

// WriteFileString writes string content to text file.
func WriteFileString(path string, name string, value string) error {
        fo, err := os.Create(path + "/" + name)
        if err != nil {
                return err
        }

        if _, err := fo.WriteString(value); err != nil {
                return err
        }

        return nil
}

// CreateAndOpenFile creates file and open it foe recording.
func CreateAndOpenFile(path string, fileName string, perms ...os.FileMode) (io.Writer, error) {
        perm := OwnerWritePerm
        if len(perms) != 0 {
                perm = perms[0]
        }

        filePath := path
        if filePath != "" {
                // Not dependent on the transmitted "/".
                filePath = strings.TrimRight(filePath, "/") + "/"

                if err := MkdirAll(path); err != nil {
                        return nil, err
                }
        }

        filePath += fileName

        f, err := os.OpenFile(filePath, os.O_WRONLY|os.O_CREATE|os.O_APPEND, perm)
        if err != nil {
                return nil, err
        }

        return f, nil
}

// StatTimes gets file stats info.
func StatTimes(name string) (atime, mtime, ctime time.Time, err error) {
        info, err := os.Stat(name)
        if err != nil {
                return
        }

        mtime = info.ModTime()
        stat := info.Sys().(*syscall.Stat_t) //nolint
        atime = time.Unix(stat.Atim.Sec, stat.Atim.Nsec)
        ctime = time.Unix(stat.Ctim.Sec, stat.Ctim.Nsec)

        return
}

// MkdirAll creates a directory named path,
// along with any necessary parents, and returns nil,
// or else returns an error.
// The permission bits perm (before umask) are used for all
// directories that MkdirAll creates.
func MkdirAll(path string, perm ...os.FileMode) error {
        _, err := os.Stat(path)

        if os.IsNotExist(err) {
                p := os.ModePerm
                if len(perm) != 0 {
                        p = perm[0]
                }

                return os.MkdirAll(path, p)
        }

        return err
}

// GetDirNamesInFolder returns slice with directory names in path.
func GetDirNamesInFolder(path string) ([]string, error) {
        items, err := os.ReadDir(path)
        if err != nil {
                return make([]string, 0), fmt.Errorf("scan dirrectory: %w", err)
        }

        names := make([]string, 0, len(items))

        for _, item := range items {
                if item.IsDir() {
                        names = append(names, item.Name())
                }
        }

        return names, nil
}

// GetFileNamesInFolder returns slice with file names in path.
func GetFileNamesInFolder(path string) ([]string, error) {
        items, err := os.ReadDir(path)
        if err != nil {
                return make([]string, 0), fmt.Errorf("scan dirrectory: %w", err)
        }

        names := make([]string, 0, len(items))

        for _, item := range items {
                if !item.IsDir() {
                        names = append(names, item.Name())
                }
        }

        return names, nil
}

// GetAbsPath returns an absolute path based on the input path and a default path.
// It handles three cases for the input path:
//  1. If the path is already absolute (starts with "/"), home-relative (starts with "~/"),
//     or relative to current directory (starts with "./"), it returns the path as-is.
//  2. If the path is empty, it uses the defaultPath instead.
//  3. For all other cases, it treats the path as relative to the executable's directory.
//
// Parameters:
//   - path: The input path to process (can be empty, absolute, or relative)
//   - defaultPath: The default path to use if input path is empty
//
// Returns:
//   - string: The resulting absolute path
//   - error: Any error that occurred while getting the executable's directory
//
// Example usage:
//
//        absPath, err := GetAbsPath("config.json", "/etc/default/config.json")
//        // Returns "/path/to/executable/config.json" if no error
func GetAbsPath(path, defaultPath string) (string, error) {
        // Use default path if input path is empty
        if path == "" {
                path = defaultPath
        }

        // Check if path is already in absolute, home-relative, or current-directory-relative form
        if path != "" && (string(path[0]) == "/" || strings.HasPrefix(path, "~/") || strings.HasPrefix(path, "./")) {
                return path, nil
        }

        // Get the absolute path of the directory containing the executable
        home, err := filepath.Abs(filepath.Dir(os.Args[0]))
        if err != nil {
                return "", err
        }

        // Combine executable directory with the relative path
        path = home + "/" + path

        return path, nil
}

// ClearDir removes all contents of the specified directory while preserving
// the directory itself. It traverses the directory recursively, deleting all
// files, subdirectories, and symbolic links.
//
// Parameters:
//   - dir - string path to the directory to be cleared
//
// Returns:
//   - error - nil on success, or any error encountered during the operation
//
// Behavior details:
//   - Preserves the original directory (only removes its contents)
//   - Handles nested directory structures recursively
//   - Follows symbolic links when deleting (removes link targets)
//   - Stops and returns on the first error encountered
//   - Returns nil if directory doesn't exist (consistent with os.RemoveAll)
//
// Example usage:
//
//        err := ClearDir("/tmp/workdir")
//        if err != nil {
//            log.Fatal("Failed to clear directory:", err)
//        }
//
// Warning:
//   - This is a destructive operation - deleted files cannot be recovered
//   - The function will remove ALL contents without confirmation
//   - Ensure proper permissions exist for all files/subdirectories.
func ClearDir(dir string) error {
        entries, err := os.ReadDir(dir)
        if err != nil {
                return err
        }

        for _, entry := range entries {
                if err := os.RemoveAll(filepath.Join(dir, entry.Name())); err != nil {
                        return err
                }
        }

        return nil
}

// Package httpclient provides a configurable HTTP client with sensible defaults
// and helper methods for making HTTP requests.
package httpclient

import (
        "context"
        "errors"
        "fmt"
        "io"
        "net"
        "net/http"
)

var (
        // ErrWrongStatusCode is returned when the server responds with an unexpected HTTP status code.
        ErrWrongStatusCode = errors.New("wrong status code")

        // ErrEmptyResponse is returned when the server response is nil and error is nil.
        ErrEmptyResponse = errors.New("empty response")
)

// Client wraps http.Client to provide additional functionality and configuration.
// It embeds the standard http.Client to expose all its methods while adding custom behavior.
type Client struct {
        http.Client
}

// New creates and returns a new Client instance configured with the given settings.
// The configuration includes timeouts, transport settings, and dialer parameters.
func New(cfg *Config) *Client {
        cfg.SetDefaults()

        return &Client{
                http.Client{
                        Timeout: cfg.Timeout,
                        Transport: &http.Transport{
                                DialContext: (&net.Dialer{
                                        Timeout:       cfg.Dialer.Timeout,
                                        Deadline:      cfg.Dialer.Deadline,
                                        FallbackDelay: cfg.Dialer.FallbackDelay,
                                        KeepAlive:     cfg.Dialer.KeepAlive,
                                }).DialContext,
                                TLSHandshakeTimeout: cfg.TLSHandshakeTimeout,
                        },
                },
        }
}

// SendRequest executes an HTTP request with the given method, URI, and optional body.
// It handles the full request lifecycle including context cancellation, error handling,
// and response processing.
//
// Parameters:
//   - ctx: Context for cancellation and timeout control
//   - method: HTTP method (GET, POST, etc.)
//   - uri: Target URL for the request
//   - body: Request body content (can be nil)
//
// Returns:
//   - Response body as byte slice if successful
//   - Error if request fails, response status is not 200 OK, or body read fails.
func (c *Client) SendRequest(ctx context.Context, method, uri string, body io.Reader) ([]byte, error) {
        req, err := http.NewRequestWithContext(ctx, method, uri, body)
        if err != nil {
                return nil, err
        }

        res, err := c.Do(req)
        if err != nil {
                return nil, err
        }

        if res == nil {
                return nil, ErrEmptyResponse
        }

        defer res.Body.Close()

        if res.StatusCode != http.StatusOK {
                return nil, fmt.Errorf("%w: %d %s", ErrWrongStatusCode, res.StatusCode, res.Status)
        }

        resBody, err := io.ReadAll(res.Body)
        if err != nil {
                return nil, err
        }

        return resBody, nil
}

package httpclient

import "time"

const (
        // DefaultTimeout is the default timeout for general network operations.
        DefaultTimeout = 10 * time.Second

        // DefaultTLSHandshakeTimeout is the default timeout for TLS handshake operations.
        DefaultTLSHandshakeTimeout = 5 * time.Second

        // DefaultDialerTimeout is the default timeout for establishing new connections.
        DefaultDialerTimeout = 5 * time.Second
)

// Config represents configuration settings for network connections.
// It includes timeouts and dialer-specific parameters that can be
// unmarshalled from either JSON or YAML formats.
type Config struct {
        // Timeout specifies the maximum duration for the entire connection
        // process. Zero means no timeout.
        Timeout time.Duration `json:"timeout" yaml:"timeout"`

        // TLSHandshakeTimeout specifies the maximum duration to wait for
        // a TLS handshake to complete. Zero means no timeout.
        TLSHandshakeTimeout time.Duration `json:"tls_handshake_timeout" yaml:"tls_handshake_timeout"`

        // Dialer contains configuration specific to the connection dialer.
        Dialer struct {
                // Timeout is the maximum duration for dialing a connection.
                // This includes name resolution if required.
                Timeout time.Duration `json:"timeout" yaml:"timeout"`

                // Deadline specifies an absolute time point after which
                // dial operations will fail.
                // Zero means no deadline.
                Deadline time.Time `json:"deadline" yaml:"deadline"`

                // FallbackDelay specifies the length of time to wait before
                // spawning a fallback connection, when dual-stack IPv4/IPv6
                // is enabled.
                FallbackDelay time.Duration `json:"fallback_delay" yaml:"fallback_delay"`

                // KeepAlive specifies the keep-alive period for network
                // connections. If zero, keep-alives are not enabled.
                KeepAlive time.Duration `json:"keep_alive" yaml:"keep_alive"`
        } `json:"dialer" yaml:"dialer"`
}

// SetDefaults initializes the configuration with default values for any unset fields.
// If Timeout, TLSHandshakeTimeout, or Dialer.Timeout are zero (unset), they will be
// populated with their respective default values.
//
// This ensures the configuration is always valid and prevents zero-values from causing
// unexpected behavior in network operations.
func (cfg *Config) SetDefaults() {
        // Set default general operation timeout if not specified.
        if cfg.Timeout == 0 {
                cfg.Timeout = DefaultTimeout
        }

        // Set default TLS handshake timeout if not specified.
        if cfg.TLSHandshakeTimeout == 0 {
                cfg.TLSHandshakeTimeout = DefaultTLSHandshakeTimeout
        }

        // Set default dialer connection timeout if not specified.
        if cfg.Dialer.Timeout == 0 {
                cfg.Dialer.Timeout = DefaultDialerTimeout
        }
}

package problemdetails

import (
        "encoding/json"
        "errors"

        "github.com/labstack/echo/v4"
        "github.com/outdead/golibs/httpserver/validator"
)

type Binder struct {
        logger Logger
}

// NewBinder creates and returns new Binder instance.
func NewBinder(l Logger) *Binder {
        return &Binder{
                logger: l,
        }
}

// Bind parses echo Context to data structure. Returns en error if data is invalid.
func (b *Binder) Bind(c echo.Context, req interface{}) error {
        if err := c.Bind(req); err != nil {
                var t *json.UnmarshalTypeError
                if ok := errors.As(err, &t); ok {
                        return validator.NewValidationError(t.Field, err.Error())
                }

                // TODO: There is no way to get field names of int, time.Time, uuid.CartUUID if got incorrect data.
                return validator.NewValidationError("", err.Error())
        }

        return nil
}

// BindAndValidate parses echo Context to data structure and validate received
// data. Returns en error if data is invalid.
func (b *Binder) BindAndValidate(c echo.Context, req interface{}) error {
        if err := b.Bind(c, req); err != nil {
                return err
        }

        return c.Validate(req)
}

package problemdetails

import (
        "errors"
        "fmt"
        "net/http"

        "github.com/labstack/echo/v4"
        "github.com/outdead/golibs/httpserver/validator"
)

// Error types for RFC-7807 Problem Details format.
// See: https://datatracker.ietf.org/doc/html/rfc7807
const (
        TypeValidation          = "validation-error"
        TypeUnauthorized        = "unauthorized"
        TypeForbidden           = "forbidden"
        TypeNotFound            = "data-not-found"
        TypeInternalServerError = "internal-server-error"
        TypeHTTP                = "http-error"
)

// Titles for RFC-7807 Problem Details format.
const (
        TitleValidation          = "Your request parameters didn't validate."
        TitleUnauthorized        = "Your request has not been applied."
        TitleForbidden           = "Your request has been forbidden."
        TitleNotFound            = "Not Found"
        TitleInternalServerError = "Internal Server Error"
)

// Statuses for RFC-7807 Problem Details format.
const (
        StatusValidation          = http.StatusBadRequest          // 400
        StatusUnauthorized        = http.StatusUnauthorized        // 401
        StatusForbidden           = http.StatusForbidden           // 403
        StatusNotFound            = http.StatusNotFound            // 404
        StatusBusinessError       = http.StatusUnprocessableEntity // 422
        StatusInternalServerError = http.StatusInternalServerError // 500
)

// Error contains error in RFC-7807 Problem Details format.
type Error struct {
        Type   string `json:"type"`
        Title  string `json:"title"`
        Status int    `json:"status"`
        Detail string `json:"detail,omitempty"`
        // InvalidParams contains the explanation of errors in RFC-7807 format.
        InvalidParams validator.ValidationErrors `json:"invalid-params,omitempty"` //nolint
}

// Error represents an error condition, with the nil value representing no error.
func (e *Error) Error() string {
        msg := fmt.Sprintf("%d %s: %s", e.Status, e.Type, e.Title)
        if len(e.InvalidParams) != 0 {
                msg += " - " + e.InvalidParams.Error()
        }

        return msg
}

func NewError(err error) *Error {
        body := NewInternalServerError()

        if ok := errors.As(err, &body); !ok {
                switch e := err.(type) { //nolint:errorlint, varnamelen // errors.As is too annoying in this case.
                case *validator.ValidationError:
                        body = NewValidationError(*e)
                        if e.Name == "" {
                                body.Detail = e.Reason
                        }
                case validator.ValidationErrors:
                        body = NewValidationError(e...)
                case *echo.HTTPError:
                        body = NewHTTPError(e)
                default:
                        if errors.Is(err, validator.ErrNotFound) {
                                body = NewNotFoundError(err)
                        }
                }
        }

        return body
}

func NewValidationError(err ...validator.ValidationError) *Error {
        return &Error{
                Type:          TypeValidation,
                Title:         TitleValidation,
                Status:        StatusValidation,
                Detail:        "",
                InvalidParams: err,
        }
}

func NewUnauthorizedError(err ...validator.ValidationError) *Error {
        return &Error{
                Type:          TypeUnauthorized,
                Title:         TitleUnauthorized,
                Status:        StatusUnauthorized,
                Detail:        "",
                InvalidParams: err,
        }
}

func NewForbiddenError(err ...validator.ValidationError) *Error {
        return &Error{
                Type:          TypeForbidden,
                Title:         TitleForbidden,
                Status:        StatusForbidden,
                Detail:        "",
                InvalidParams: err,
        }
}

func NewNotFoundError(err error) *Error {
        return &Error{
                Type:   TypeNotFound,
                Title:  TitleNotFound,
                Status: StatusNotFound,
                Detail: err.Error(),
        }
}

func NewInternalServerError() *Error {
        return &Error{
                Type:   TypeInternalServerError,
                Title:  TitleInternalServerError,
                Status: StatusInternalServerError,
                Detail: TitleInternalServerError,
        }
}

func NewHTTPError(err *echo.HTTPError) *Error {
        detail, _ := err.Message.(string)

        return &Error{
                Type:   TypeHTTP,
                Title:  http.StatusText(err.Code),
                Status: err.Code,
                Detail: detail,
        }
}

package problemdetails

import (
        "fmt"
        "net/http"

        "github.com/labstack/echo/v4"
)

// Responder wraps on echo Context to be used on echo HTTP handlers to
// construct an HTTP response.
type Responder struct {
        logger Logger
}

// NewResponder creates and returns pointer to Responder.
func NewResponder(l Logger) *Responder {
        return &Responder{l}
}

// ServeResult sends a JSON response with the result data.
func (r *Responder) ServeResult(c echo.Context, i interface{}) error {
        return c.JSON(http.StatusOK, i)
}

// ServeError sends a JSON error response with status code.
func (r *Responder) ServeError(c echo.Context, err error, logPrefix ...string) error {
        if err == nil {
                return nil
        }

        body := NewError(err)

        if body.Status == StatusInternalServerError {
                if len(logPrefix) != 0 {
                        err = fmt.Errorf("%s: %w", logPrefix[0], err)
                }

                r.logger.Error(err.Error())
        }

        return c.JSON(body.Status, body)
}

package httpserver

import (
        "context"
        "errors"
        "fmt"
        "io"
        "net/http"
        "sync"
        "time"

        "github.com/labstack/echo/v4"
        "github.com/labstack/echo/v4/middleware"
        "github.com/outdead/golibs/httpserver/problemdetails"
        "github.com/outdead/golibs/httpserver/validator"
)

// ShutdownTimeOut is time to terminate queries when quit signal given.
const ShutdownTimeOut = 10 * time.Second

// ErrLockedServer returned on repeated call Close() the HTTP server.
var ErrLockedServer = errors.New("http server is locked")

// Logger describes Error and Info functions.
type Logger interface {
        Infof(format string, args ...interface{})
        Fatalf(format string, args ...interface{})
        Debug(args ...interface{})
        Error(args ...interface{})
        Writer() io.Writer
}

// Binder represents Bind and BindAndValidate functions.
type Binder interface {
        Bind(c echo.Context, req interface{}) error
        BindAndValidate(c echo.Context, req interface{}) error
}

// Responder represents ServeResult and ServeError functions.
type Responder interface {
        ServeResult(c echo.Context, i interface{}) error
        ServeError(c echo.Context, err error, logPrefix ...string) error
}

// Option infects params to Server.
type Option func(server *Server)

// WithBinder injects Binder to Server.
func WithBinder(binder Binder) Option {
        return func(s *Server) {
                s.Binder = binder
        }
}

// WithResponder injects Responder to Server.
func WithResponder(responser Responder) Option {
        return func(s *Server) {
                s.Responder = responser
        }
}

func WithRecover(rec bool) Option {
        return func(s *Server) {
                s.recover = rec
        }
}

// A Server defines parameters for running an HTTP server.
type Server struct {
        Binder
        Responder
        Echo *echo.Echo

        logger  Logger
        errors  chan error
        recover bool
        quit    chan bool
        wg      sync.WaitGroup
}

// NewServer allocates and returns a new Server.
func NewServer(log Logger, errs chan error, options ...Option) *Server {
        s := Server{
                logger: log,
                errors: errs,

                quit: make(chan bool),
        }

        for _, option := range options {
                option(&s)
        }

        if s.Binder == nil {
                s.Binder = problemdetails.NewBinder(s.logger)
        }

        if s.Responder == nil {
                s.Responder = problemdetails.NewResponder(s.logger)
        }

        s.Echo = s.newEcho()

        return &s
}

// Serve initializes HTTP Server and runs it on received port.
func (s *Server) Serve(port string) {
        go func() {
                if err := s.Echo.Start(":" + port); err != nil && !errors.Is(err, http.ErrServerClosed) {
                        // Report error if server is not closed by Echo#Shutdown.
                        s.ReportError(fmt.Errorf("start http server: %w", err))
                }
        }()

        s.logger.Infof("http server started on port %s", port)

        s.quit = make(chan bool)
        s.wg.Add(1)

        go func() {
                defer s.wg.Done()

                <-s.quit
                s.logger.Debug("stopping http server...")

                ctx, cancel := context.WithTimeout(context.Background(), ShutdownTimeOut)
                defer cancel()

                if s.Echo != nil {
                        if err := s.Echo.Shutdown(ctx); err != nil {
                                s.ReportError(fmt.Errorf("shutdown http server: %w", err))
                        }
                }
        }()
}

// ReportError publishes error to the errors channel.
// if you do not read errors from the errors channel then after the channel
// buffer overflows the application exits with a fatal level and the
// os.Exit(1) exit code.
func (s *Server) ReportError(err error) {
        if err != nil {
                select {
                case s.errors <- err:
                default:
                        s.logger.Fatalf("http server error channel is locked: %s", err)
                }
        }
}

// Close stops HTTP Server.
func (s *Server) Close() error {
        if s.quit == nil {
                return ErrLockedServer
        }

        select {
        case s.quit <- true:
                s.wg.Wait()
                s.logger.Debug("stop http server success")

                return nil
        default:
                return ErrLockedServer
        }
}

func (s *Server) newEcho() *echo.Echo {
        e := echo.New()
        e.Use(middleware.CORS())

        if s.recover {
                e.Use(middleware.Recover())
        }

        e.Validator = validator.New()

        e.Logger.SetOutput(s.logger.Writer())
        e.HideBanner = true
        e.HidePort = true

        e.HTTPErrorHandler = s.httpErrorHandler

        return e
}

// httpErrorHandler customizes error response.
// @source: https://github.com/labstack/echo/issues/325
func (s *Server) httpErrorHandler(err error, c echo.Context) {
        if err = s.ServeError(c, err); err != nil {
                s.ReportError(fmt.Errorf("error handle: %w", err))
        }
}

package validator

import "errors"

var (
        // ErrNotFound is returned when data not found by identifier.
        ErrNotFound = errors.New("not found")

        // ErrDuplicateKey is returned when got duplicate key error from database.
        ErrDuplicateKey = errors.New("duplicate key")

        // ErrRequiredFieldMissed is returned when required param is empty in the request.
        ErrRequiredFieldMissed = errors.New("is required")
)

// Delimiters for text representation of errors.
const (
        ErrorSeparator = "; "
        FieldSeparator = " : "
)

// ValidationError contains field name and error message.
type ValidationError struct {
        Name   string `json:"name"`
        Reason string `json:"reason"`
}

// NewValidationError creates and returns pointer to ValidationError.
func NewValidationError(field, msg string) *ValidationError {
        return &ValidationError{Name: field, Reason: msg}
}

// Error represents an error condition, with the nil value representing no error.
func (ve *ValidationError) Error() string {
        return ve.Name + FieldSeparator + ve.Reason
}

// ValidationErrors is an array of ValidationError's for use in custom error
// messages post validation.
type ValidationErrors []ValidationError

// Error represents an error condition, with the nil value representing no error.
func (ves ValidationErrors) Error() string {
        var message string

        for i, ve := range ves {
                message += ve.Error()

                if i+1 != len(ves) {
                        message += ErrorSeparator
                }
        }

        return message
}

package validator

import (
        "errors"
        "fmt"

        "github.com/go-playground/validator/v10"
)

// Validator is a wrapper for external validation package. Allows extending validation rules.
type Validator struct {
        v *validator.Validate
}

// New returns a new instance of Validator with sane defaults.
func New() *Validator {
        return &Validator{
                v: validator.New(),
        }
}

// Validate implement Validator interface.
func (v *Validator) Validate(i interface{}) error {
        err := v.v.Struct(i)
        if err == nil {
                return nil
        }

        var vErrs validator.ValidationErrors
        if !errors.As(err, &vErrs) {
                return err
        }

        fields := make(ValidationErrors, 0, len(vErrs))

        for _, vErr := range vErrs {
                msg := fmt.Sprintf("invalid on '%s' rule", vErr.Tag())
                valErr := NewValidationError(vErr.StructNamespace(), msg)
                fields = append(fields, *valErr)
        }

        return fields
}

// Package jobticker provides a managed ticker for periodic job execution.
// It wraps time.Ticker with start/stop controls and error handling.
package jobticker

import (
        "sync"
        "time"
)

// Logger describes the minimal logging interface required by the Ticker.
// Implementations should provide Debug and Error logging capabilities.
type Logger interface {
        Debug(args ...interface{})
        Error(args ...interface{})
}

// HandlerFunc defines the signature for functions that will be executed
// on each tick interval. Returning an error will log the failure.
type HandlerFunc func() error

// Ticker manages a recurring background job with start/stop capabilities.
// It ensures safe concurrent operation and proper resource cleanup.
type Ticker struct {
        name     string
        interval time.Duration
        handler  HandlerFunc
        logger   Logger
        metrics  Metrics

        wg          sync.WaitGroup
        stopTimeout time.Duration
        mu          sync.Mutex
        quit        chan bool
        started     bool
}

// New creates a configured but unstarted Ticker instance.
// Useful when you need to delay starting the ticker.
//
// Parameters:
//
//        name     - identifier for logging.
//        handler  - function to execute on each interval.
//        interval - time between executions.
//        l        - logger implementation.
//
// Returns:
//
//        *Ticker - started ticker instance (call Close when done).
func New(name string, handler HandlerFunc, interval time.Duration, l Logger, options ...Option) *Ticker {
        ticker := &Ticker{
                name:     name,
                interval: interval,
                handler:  handler,
                logger:   l,
        }

        for _, option := range options {
                option(ticker)
        }

        return ticker
}

// Start creates and immediately starts a new Ticker instance.
// This is the preferred entry point for most use cases.
//
// Parameters:
//
//        name     - identifier for logging.
//        handler  - function to execute on each interval.
//        interval - time between executions.
//        l        - logger implementation.
//
// Returns:
//
//        *Ticker - started ticker instance (call Close when done).
func Start(name string, handler HandlerFunc, interval time.Duration, l Logger, options ...Option) *Ticker {
        ti := New(name, handler, interval, l, options...)
        ti.Start()

        return ti
}

// Start begins the ticker's execution loop in a new goroutine.
// Safe to call multiple times (will log and ignore subsequent calls).
func (t *Ticker) Start() {
        t.mu.Lock()
        defer t.mu.Unlock()

        if t.started {
                t.logger.Debug(t.name + ": already been started")

                return
        }

        t.quit = make(chan bool, 1)
        t.started = true

        t.wg.Add(1)

        go t.run()
}

// Stop initiates a graceful shutdown of the ticker. It:
// 1. Sends a quit signal to the running goroutine
// 2. Waits for the current handler to complete
// 3. Implements timeout protection for stuck handlers
//
// Safe to call multiple times - will return immediately if:
// - Ticker isn't running (!started)
// - Quit channel is already full (shutdown in progress)
//
// Logs debug messages for all edge cases (already stopped, etc.).
func (t *Ticker) Stop() {
        t.mu.Lock()
        defer t.mu.Unlock()

        if t.quit == nil || !t.started {
                t.logger.Debug(t.name + ": is not running")

                return
        }

        select {
        case t.quit <- true:
                if t.stopTimeout == 0 {
                        t.wg.Wait() // waiting for goroutines

                        return
                }

                done := make(chan struct{})
                go func() {
                        t.wg.Wait() // waiting for goroutines
                        close(done)
                }()

                select {
                case <-done:
                case <-time.After(t.stopTimeout):
                        t.logger.Error(t.name + ": forced shutdown due to timeout")
                }
        default:
                t.logger.Debug(t.name + ": close already been called")
        }
}

// IsRunning safely checks the ticker's current state.
// Returns:
//
//        true - if ticker is actively running
//        false - if stopped or never started
//
// Thread-safe atomic read - safe to call from any goroutine.
func (t *Ticker) IsRunning() bool {
        t.mu.Lock()
        defer t.mu.Unlock()

        return t.started
}

// run is the main ticker event loop running in a goroutine.
// Handles:
// - Interval tick execution
// - Graceful shutdown signals
// - Resource cleanup on exit
//
// Note: Started by Start(), stopped by Stop().
// Uses defer for guaranteed state cleanup.
func (t *Ticker) run() {
        defer func() {
                t.started = false
                t.wg.Done()
        }()

        ticker := time.NewTicker(t.interval)

        defer ticker.Stop()

        for {
                select {
                case now := <-ticker.C:
                        t.executeHandler(now)
                case <-t.quit:
                        t.logger.Debug(t.name + ": quit...")

                        return
                }
        }
}

// executeHandler safely runs the user-provided handler function.
// Provides:
// - Panic recovery
// - Error logging
// - Performance metrics collection
//
// Parameters:
//
//        startedAt - timestamp when handler execution began.
func (t *Ticker) executeHandler(startedAt time.Time) {
        defer func() {
                if r := recover(); r != nil {
                        t.logger.Error(t.name+": handler panic:", r)
                }
        }()

        err := t.handler()
        if err != nil {
                t.logger.Error(t.name+":", err)
        }

        if t.metrics != nil {
                t.metrics.Observe(t.name, startedAt, time.Since(startedAt), err)
        }
}

package jobticker

import "time"

type Option func(t *Ticker)

func WithStopTimeout(timeout time.Duration) Option {
        return func(t *Ticker) {
                t.stopTimeout = timeout
        }
}

func WithMetrics(metrics Metrics) Option {
        return func(t *Ticker) {
                t.metrics = metrics
        }
}

package logger

import (
        "fmt"
        "io"
        "time"

        "github.com/bwmarrin/discordgo"
        "github.com/outdead/discordbotrus"
        "github.com/outdead/golibs/files"
        "github.com/sirupsen/logrus"
)

// Hook includes logrus.Hook interface and describes Close method.
type Hook interface {
        logrus.Hook
        Close() error
}

// Logger wraps logrus.Logger with additional configuration and methods.
type Logger struct {
        *logrus.Logger
        config Config

        discordHook    Hook
        discordSession *discordgo.Session
}

// New creates and returns a new Logger instance with default JSON formatter.
// The returned logger has no output set by default (uses stderr).
func New() *Logger {
        logger := &Logger{
                Logger: logrus.New(),
        }
        logger.Formatter = new(logrus.JSONFormatter)

        return logger
}

// AddOutput adds additional output writer to the logger.
// This allows writing logs to multiple destinations simultaneously.
// The new writer will be used in addition to any existing outputs.
func (log *Logger) AddOutput(w io.Writer) {
        log.Out = io.MultiWriter(log.Out, w)
}

// SetConfig applies a new configuration to the Logger and configures all required outputs.
// It handles the following configuration aspects:
//   - Core logger settings (log level)
//   - File output configuration (if specified)
//   - Discord hook setup (if configured)
//
// Parameters:
//   - cfg: Pointer to Config struct containing all logger settings. Must not be nil.
//   - options: Optional variadic list of Option functions to modify logger behavior.
//
// Returns:
//   - error: Returns ErrInvalidConfig if cfg is nil or contains invalid settings.
//     Returns file creation errors if file logging is configured.
//     Returns Discord hook initialization errors if Discord logging is configured.
//
// Usage:
//
//        err := logger.SetConfig(&Config{
//            Level: "info",
//            File: FileConfig{Path: "/var/log", Layout: "2006-01-02.log"},
//        })
//        if err != nil {
//            // handle error
//        }
//
// Notes:
//   - This function is not concurrent-safe and should not be called while the logger is in use.
//   - Replaces all previous configuration when called.
//   - File outputs are created immediately if specified in config.
//   - Discord hooks are initialized immediately if configured.
func (log *Logger) SetConfig(cfg *Config, options ...Option) error {
        if cfg == nil {
                return ErrInvalidConfig
        }

        log.config = *cfg

        for _, option := range options {
                option(log)
        }

        if cfg.Level != "" {
                logrusLevel, err := logrus.ParseLevel(cfg.Level)
                if err != nil {
                        return fmt.Errorf("%w: %w", ErrInvalidConfig, err)
                }

                log.Level = logrusLevel
        }

        if log.config.File.Layout != "" {
                file, err := files.CreateAndOpenFile(log.config.File.Path, time.Now().Format(log.config.File.Layout))
                if err != nil {
                        return fmt.Errorf("create logger file hook: %w", err)
                }

                log.AddOutput(file)
        }

        if cfg.Discord.ChannelID != "" {
                var err error

                if cfg.Discord.Token != "" {
                        log.discordHook, err = discordbotrus.New(&cfg.Discord)
                } else {
                        log.discordHook, err = discordbotrus.New(&cfg.Discord, discordbotrus.WithSession(log.discordSession))
                }

                if err != nil {
                        return fmt.Errorf("create logrus discord hook error: %w", err)
                }

                log.AddHook(log.discordHook)
        }

        return nil
}

// Writer returns the current writer used by the logger.
// This can be used to redirect the logger's output or integrate with other systems.
func (log *Logger) Writer() io.Writer {
        return log.Logger.Writer()
}

// Close implements the io.Closer interface for the Logger.
// Currently, it doesn't perform any cleanup but is provided for future compatibility.
func (log *Logger) Close() error {
        if log.discordHook != nil {
                return log.discordHook.Close()
        }

        return nil
}

package logger

import (
        "github.com/bwmarrin/discordgo"
)

type Option func(log *Logger)

func WithDiscordSession(session *discordgo.Session) Option {
        return func(log *Logger) {
                log.discordSession = session
        }
}

package random

import (
        crand "crypto/rand"
        "math/big"
        mrand "math/rand"
)

func IntWeak(from, to int) int {
        return from + mrand.Intn(to-from+1) //nolint:gosec // I'm ok with unsecure here.
}

func IntStrong(from, to int) int {
        num, _ := crand.Int(crand.Reader, big.NewInt(int64(to-from+1)))

        return from + int(num.Int64())
}

package times

import (
        "fmt"
        "time"
)

// FmtDuration formats a time.Duration into a human-readable string with optional seconds.
// The duration is rounded to the nearest minute (or second) before formatting.
//
// The function provides two formatting modes:
// - Default: "[-]XXhXXm" format (hours and minutes)
// - With seconds: "[-]XXhXXmXXs" format (when secs[0] is true)
//
// Parameters:
//   - duration: The time duration to format (can be negative)
//   - secs: Optional boolean flag to include seconds in output
//
// Returns:
//   - Formatted duration string with leading zero padding and optional sign
func FmtDuration(duration time.Duration, withSeconds ...bool) string {
        sign := ""

        showSeconds := len(withSeconds) > 0 && withSeconds[0]

        if showSeconds {
                duration = duration.Round(time.Second)
        } else {
                duration = duration.Round(time.Minute)
        }

        if negative := duration < 0; negative {
                duration = -duration
                sign = "-"
        }

        hours := duration / time.Hour
        duration -= hours * time.Hour //nolint:durationcheck // Intentional duration math - safe conversion
        minutes := duration / time.Minute

        if !showSeconds {
                return fmt.Sprintf("%s%02dh%02dm", sign, hours, minutes)
        }

        duration -= minutes * time.Minute //nolint:durationcheck // Intentional duration math - safe conversion
        seconds := duration / time.Second

        return fmt.Sprintf("%s%02dh%02dm%02ds", sign, hours, minutes, seconds)
}

package times

import (
        "errors"
        "fmt"
        "time"
)

var ErrInvalidTimeFormat = errors.New("invalid time format")

// ParseOnlyTime parses a time string into hours, minutes, and seconds components.
// It supports multiple time formats with flexible parsing:
//   - "HH:MM:SS" (full time format)
//   - "HH:MM"    (hours and minutes, seconds default to 0)
//   - "HH"       (only hours, minutes and seconds default to 0)
//
// The function attempts each format in order and returns the first successful match.
// All returned time components are unsigned integers.
//
// Parameters:
//
//        strtime - string containing the time to parse (e.g., "14:30:00", "09:45", "23")
//
// Returns:
//
//        hour   - parsed hour (0-23)
//        minute - parsed minute (0-59)
//        second - parsed second (0-59)
//        err    - error if parsing fails, wrapping ErrInvalidTimeFormat with the invalid input
//
// Example usage:
//
//        h, m, s, err := ParseOnlyTime("08:30:15") // returns 8, 30, 15, nil
//        h, m, s, err := ParseOnlyTime("12:45")    // returns 12, 45, 0, nil
//        h, m, s, err := ParseOnlyTime("invalid")  // returns 0, 0, 0, error.
func ParseOnlyTime(strtime string) (hour, minute, second uint, err error) {
        formats := []string{
                "15:04:05", // Full format (HH:MM:SS)
                "15:04",    // Hours and minutes (HH:MM)
                "15",       // Only hours (HH)
        }

        for _, layout := range formats {
                if t, err := time.Parse(layout, strtime); err == nil {
                        // #nosec G115 - Conversion is safe because time.Time methods
                        // always return valid ranges (Hour: 0-23, Minute/Second: 0-59)
                        return uint(t.Hour()), uint(t.Minute()), uint(t.Second()), nil
                }
        }

        return 0, 0, 0, fmt.Errorf("%w: %q", ErrInvalidTimeFormat, strtime)
}

// ParseOnlyTimeSafe tries to parse time string, returns zero values (0,0,0) on failure.
// Silent version that never fails - ideal for non-critical time parsing.
func ParseOnlyTimeSafe(strtime string) (hour, minute, second uint) {
        hour, minute, second, _ = ParseOnlyTime(strtime)

        return
}

// Package times provides custom time handling utilities.
package times

import (
        "errors"
        "fmt"
        "time"
)

// DateTimeLayout defines the standard format for date-time strings
// Uses Go's reference time format: Mon Jan 2 15:04:05 MST 2006.
const DateTimeLayout = "2006-01-02 15:04:05"

// ErrUndefinedDateTime is returned when an unsupported type is encountered.
var ErrUndefinedDateTime = errors.New("undefined datetime")

// SQLTime is a custom type that wraps time.Time to provide custom scanning behavior.
type SQLTime time.Time

// Scan implements the sql.Scanner interface for SQLTime
// It converts various input types into a SQLTime value.
func (t *SQLTime) Scan(v interface{}) error {
        if v == nil {
                return nil
        }

        switch value := v.(type) {
        case time.Time:
                // Direct assignment if input is time.Time
                *t = SQLTime(value)
        case string:
                // Parse string using the defined layout
                vt, err := time.Parse(DateTimeLayout, value)
                if err != nil {
                        return err
                }

                *t = SQLTime(vt)
        case []byte:
                // Handle byte slices (common in database drivers)
                vt, err := time.Parse(DateTimeLayout, string(value))
                if err != nil {
                        return err
                }

                *t = SQLTime(vt)
        default:
                // Return error for unsupported types
                return fmt.Errorf("%w: %v", ErrUndefinedDateTime, value)
        }

        return nil
}

// Package ttlcounter provides a thread-safe TTL counter.
// All methods are safe for concurrent use by multiple goroutines.
// Could be useful for scenarios like rate limiting, tracking recent
// activity, or any case where you need to count events but only care
// about recent ones.
package ttlcounter

import (
        "sync"
        "time"
)

const (
        // DefaultTTL is the default time-to-live in seconds for counter items.
        DefaultTTL = 1 * time.Second

        // DefaultVacuumInterval is the default interval for automatic cleanup of expired items.
        DefaultVacuumInterval = 1 * time.Second
)

// Item represents a counter item with a value and last access timestamp.
type Item struct {
        value  int   // The current counter value
        access int64 // Unix timestamp of last access
}

func (item *Item) Expired(ttl time.Duration) bool {
        return item.access+ttl.Nanoseconds() <= time.Now().UnixNano()
}

// Counter is a TTL-based counter that automatically expires old entries.
type Counter struct {
        mu      sync.Mutex
        items   map[string]*Item
        ttl     time.Duration
        stop    chan struct{}
        stopped sync.Once
}

// New creates a new Counter with the specified TTL (in seconds)
// and starts a background goroutine to periodically clean up expired items
// If ttl <= 0, DefaultTTL will be used.
func New(ttl time.Duration) *Counter {
        if ttl <= 0 {
                ttl = DefaultTTL
        }

        counter := &Counter{
                items: make(map[string]*Item),
                ttl:   ttl,
                stop:  make(chan struct{}),
        }

        // Start a background goroutine to clean up expired items every second
        go counter.vacuumLoop()

        return counter
}

// Len returns the current number of items in the counter.
func (c *Counter) Len() int {
        c.mu.Lock()
        defer c.mu.Unlock()

        return len(c.items)
}

// Keys returns a slice of all existing keys in the counter
// The order of keys is not guaranteed.
func (c *Counter) Keys() []string {
        c.mu.Lock()
        defer c.mu.Unlock()

        keys := make([]string, 0, len(c.items))
        for key := range c.items {
                keys = append(keys, key)
        }

        return keys
}

// Inc increments the counter for the specified key
// If the key doesn't exist, it creates a new counter starting at 1
// Updates the last access time to current time.
func (c *Counter) Inc(key string) {
        c.mu.Lock()
        defer c.mu.Unlock()

        now := time.Now()

        item, ok := c.items[key]
        if !ok {
                item = &Item{}
                c.items[key] = item
        }

        item.value++
        item.access = now.UnixNano()
}

// Get returns the current value for the specified key
// Returns 0 if the key doesn't exist
// Note: This doesn't update the last access time.
func (c *Counter) Get(key string) int {
        c.mu.Lock()
        defer c.mu.Unlock()

        var value int

        if item, ok := c.items[key]; ok {
                if item.Expired(c.ttl) {
                        return 0
                }

                value = item.value
        }

        return value
}

// Touch returns the current value for the specified key and resets last access time.
// Returns 0 if the key doesn't exist.
func (c *Counter) Touch(key string) int {
        c.mu.Lock()
        defer c.mu.Unlock()

        now := time.Now()

        var value int

        if item, ok := c.items[key]; ok {
                if item.Expired(c.ttl) {
                        return 0
                }

                value = item.value
                item.access = now.UnixNano()
        }

        return value
}

// Del removes the specified key from the counter.
// If the key doesn't exist, nothing happens.
func (c *Counter) Del(key string) {
        c.mu.Lock()
        defer c.mu.Unlock()

        delete(c.items, key)
}

// Expire returns how many seconds until the key expires
// Returns a negative number if the key is already expired
// Returns 0 if the key doesn't exist.
func (c *Counter) Expire(key string) time.Duration {
        c.mu.Lock()
        defer c.mu.Unlock()

        now := time.Now().UnixNano()

        if item, ok := c.items[key]; ok {
                remaining := item.access + c.ttl.Nanoseconds() - now
                if remaining > 0 {
                        return time.Duration(remaining)
                }

                return 0
        }

        return 0
}

// Vacuum cleans up expired items based on the provided current time
// Called automatically by the background goroutine.
func (c *Counter) Vacuum() {
        c.mu.Lock()
        defer c.mu.Unlock()

        for key, item := range c.items {
                if item.Expired(c.ttl) {
                        delete(c.items, key)
                }
        }
}

// TTL returns the configured time-to-live in seconds.
func (c *Counter) TTL() time.Duration {
        return c.ttl
}

// SetTTL updates the time-to-live for counter items
// If ttl <= 0, DefaultTTL will be used.
func (c *Counter) SetTTL(ttl time.Duration) {
        c.mu.Lock()
        defer c.mu.Unlock()

        if ttl <= 0 {
                ttl = DefaultTTL
        }

        c.ttl = ttl
}

// Close stops the background cleanup goroutine
// Safe to call multiple times.
func (c *Counter) Close() {
        c.stopped.Do(func() {
                close(c.stop)
        })
}

// vacuumLoop runs in a goroutine and periodically calls Vacuum
// until the counter is closed.
func (c *Counter) vacuumLoop() {
        ticker := time.NewTicker(DefaultVacuumInterval)
        defer ticker.Stop()

        for {
                select {
                case <-ticker.C:
                        c.Vacuum()
                case <-c.stop:
                        return
                }
        }
}