package confiq

import (
        "encoding/json"
        "errors"
        "fmt"
        "net"
        "net/url"
        "reflect"
        "time"
)

var (
        errIPCannotBeNil             = errors.New("IP address cannot be nil")
        errCannotParseIP             = errors.New("cannot parse IP address")
        errURLCannotBeNil            = errors.New("URL cannot be nil")
        errCannotParseURL            = errors.New("cannot parse URL")
        errDurationCannotBeNil       = errors.New("duration cannot be nil")
        errCannotParseDuration       = errors.New("cannot parse duration")
        errTimeCannotBeNil           = errors.New("time cannot be nil")
        errCannotParseTime           = errors.New("cannot parse time")
        errCannotParseNonStringTime  = errors.New("cannot parse time from non-string type")
        errJSONRawMessageCannotBeNil = errors.New("JSON raw message cannot be nil")
        errCannotParseJSONRawMessage = errors.New("cannot marshal source value to JSON")
)

type typeDefinition struct {
        kind     reflect.Kind
        pkgPath  string
        typeName string
}

var commonDecoders = map[typeDefinition]decoderFunc{
        {reflect.Int64, "time", "Duration"}:            decodeDuration,
        {reflect.Slice, "net", "IP"}:                   decodeIP,
        {reflect.Slice, "encoding/json", "RawMessage"}: decodeJSONRawMessage,
        {reflect.Struct, "time", "Time"}:               decodeTime,
        {reflect.Struct, "net/url", "URL"}:             decodeURL,
}

func getCommonDecoder(targetValType reflect.Type) decoderFunc {
        if targetValType.Kind() == reflect.Ptr {
                targetValType = targetValType.Elem()
        }

        if decoder, decoderFound := commonDecoders[typeDefinition{targetValType.Kind(), targetValType.PkgPath(), targetValType.Name()}]; decoderFound {
                return decoder
        }

        return nil
}

func decodeDuration(targetValue reflect.Value, sourceValue any) error {
        if sourceValue == nil {
                return errDurationCannotBeNil
        }

        parsedDuration, err := time.ParseDuration(castToString(sourceValue))
        if err != nil {
                return fmt.Errorf("%w: %w", errCannotParseDuration, err)
        }

        targetValue.SetInt(int64(parsedDuration))

        return nil
}

func decodeIP(targetValue reflect.Value, sourceValue any) error {
        if sourceValue == nil {
                return errIPCannotBeNil
        }

        parsedIP := net.ParseIP(castToString(sourceValue))
        if parsedIP == nil {
                return errCannotParseIP
        }

        targetValue.Set(reflect.ValueOf(parsedIP))

        return nil
}

func decodeJSONRawMessage(targetValue reflect.Value, sourceValue any) error {
        if sourceValue == nil {
                return errJSONRawMessageCannotBeNil
        }

        marshaledSourceValue, err := json.Marshal(sourceValue)
        if err != nil {
                return fmt.Errorf("%w: %w", errCannotParseJSONRawMessage, err)
        }

        targetValue.Set(reflect.ValueOf(marshaledSourceValue))

        return nil
}

func decodeTime(targetValue reflect.Value, sourceValue any) error {
        if sourceValue == nil {
                return errTimeCannotBeNil
        }

        if timeValue, isTimeValue := sourceValue.(time.Time); isTimeValue {
                targetValue.Set(reflect.ValueOf(timeValue))

                return nil
        }

        stringValue, isStringValue := sourceValue.(string)
        if !isStringValue {
                return fmt.Errorf("%w: %T", errCannotParseNonStringTime, sourceValue)
        }

        parsedTime, err := time.Parse(time.RFC3339, stringValue)
        if err != nil {
                return fmt.Errorf("%w: %w", errCannotParseTime, err)
        }

        targetValue.Set(reflect.ValueOf(parsedTime))

        return nil
}

func decodeURL(targetValue reflect.Value, sourceValue any) error {
        if sourceValue == nil {
                return errURLCannotBeNil
        }

        parsedURL, err := url.Parse(castToString(sourceValue))
        if err != nil {
                return fmt.Errorf("%w: %w", errCannotParseURL, err)
        }

        targetValue.Set(reflect.ValueOf(parsedURL))

        return nil
}

// Package confiq is a Go package for populating structs from structured data formats such JSON, TOML, YAML or Env.
package confiq

import (
        "errors"
        "fmt"
        "reflect"
)

const defaultTag = "cfg"

var (
        errCannotGetKeyFromNonMap     = errors.New("cannot get key from non-map type")
        errKeyNotFound                = errors.New("key not found")
        errCannotGetIndexFromNonSlice = errors.New("cannot get index from non-slice type")
        errIndexOutOfBounds           = errors.New("index out of bounds")
)

type decoder struct {
        tag string
}

type decodeSettings struct {
        strict bool
        prefix string
}

// ConfigSet is a configuration set that can be used to load and decode configuration values into a struct.
type ConfigSet struct {
        value   *any
        decoder *decoder
}

// New creates a new ConfigSet with the given options.
func New(options ...configSetOption) *ConfigSet {
        var (
                value     any
                configSet = &ConfigSet{
                        value:   &value,
                        decoder: &decoder{tag: defaultTag},
                }
        )

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

        return configSet
}

// Get returns the configuration value at the given path as an interface.
func (c *ConfigSet) Get(path string) (any, error) {
        return c.getByPath(path)
}

func (c *ConfigSet) getByPath(path string) (any, error) {
        currentValue := *c.value

        for path != "" {
                var currentSegment segment

                currentSegment, path = getNextSegment(path)

                switch v := currentSegment.(type) {
                case keySegment:
                        segmentValue, err := getMapValue(currentValue, v.asString())
                        if err != nil {
                                return nil, err
                        }

                        currentValue = segmentValue
                case indexSegment:
                        segmentValue, err := getSliceValue(currentValue, v.asInt())
                        if err != nil {
                                return nil, err
                        }

                        currentValue = segmentValue
                }
        }

        return currentValue, nil
}

func getMapValue(originMap any, key string) (any, error) {
        v := reflect.ValueOf(originMap)
        if v.Kind() != reflect.Map {
                return nil, fmt.Errorf("%w: %s(%T)", errCannotGetKeyFromNonMap, key, originMap)
        }

        value := v.MapIndex(reflect.ValueOf(key))
        if !value.IsValid() {
                return nil, fmt.Errorf("%w: %s", errKeyNotFound, key)
        }

        return value.Interface(), nil
}

func getSliceValue(originSlice any, index int) (any, error) {
        v := reflect.ValueOf(originSlice)
        if v.Kind() != reflect.Slice {
                return nil, fmt.Errorf("%w: %d(%T)", errCannotGetIndexFromNonSlice, index, originSlice)
        }

        if v.Len() <= index || index < 0 {
                return nil, fmt.Errorf("%w: %d", errIndexOutOfBounds, index)
        }

        return v.Index(index).Interface(), nil
}

package confiq

import (
        "encoding"
        "errors"
        "fmt"
        "reflect"
        "strings"
)

const sliceSplitChar = ";"

// Collection of decode errors.
var (
        ErrInvalidTarget        = errors.New("target must be non-nil pointer to a slice, map or struct that has at least one exported field with a the configured tag")
        ErrNoTargetFieldsAreSet = errors.New("none of the target fields were set from config values")
)

var (
        errCannotDecodeCustomTypeField       = errors.New("cannot decode field with custom decoder")
        errCannotDecodeNonRequiredField      = errors.New("cannot decode non-strict field")
        errCannotDecodeNonSliceValueToTarget = errors.New("cannot decode non-slice value to target")
        errCannotUnmarshalPrimitive          = errors.New("cannot unmarshal primitive as text")
        errCannotHaveDefaultForRequiredField = errors.New("cannot have default value for required field")
        errUnsupportedPrimitiveKind          = errors.New("unsupported primitive kind")
)

type (
        decoderFunc      func(targetField reflect.Value, value any) error
        fieldDecoderFunc func(targetField reflect.Value, value any, strict bool) (int, error)
)

type fieldOptions struct {
        path         string
        strict       bool
        required     bool
        defaultValue *string
}

type Decoder interface {
        Decode(value any) error
}

// Decode decodes the configuration values into the target struct.
func (c *ConfigSet) Decode(target interface{}, options ...decodeOption) error {
        return c.decode(target, options)
}

func (c *ConfigSet) decode(target interface{}, options []decodeOption) error {
        decodeSettings := &decodeSettings{
                strict: false,
                prefix: "",
        }

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

        targetValue := reflect.ValueOf(target)
        if targetValue.Kind() != reflect.Ptr || targetValue.IsNil() {
                return ErrInvalidTarget
        }

        targetValue = targetValue.Elem()

        decodedFieldCount, err := c.decodeField(targetValue, fieldOptions{
                path:         decodeSettings.prefix,
                strict:       decodeSettings.strict,
                required:     false,
                defaultValue: nil,
        })
        if err != nil {
                return err
        } else if decodedFieldCount == 0 {
                return ErrNoTargetFieldsAreSet
        }

        return nil
}

func (c *ConfigSet) getFieldConfigValue(fieldOpts fieldOptions) (any, error) {
        if fieldOpts.required && fieldOpts.defaultValue != nil {
                return nil, fmt.Errorf("%w: %s", errCannotHaveDefaultForRequiredField, fieldOpts.path)
        }

        configValue, err := c.getByPath(fieldOpts.path)
        if err != nil {
                if fieldOpts.required {
                        return nil, fmt.Errorf("field is required: %w", err)
                }

                if fieldOpts.defaultValue != nil {
                        return *fieldOpts.defaultValue, nil
                }

                return nil, errCannotDecodeNonRequiredField
        }

        return configValue, nil
}

func (c *ConfigSet) decodeField(targetValue reflect.Value, fieldOpts fieldOptions) (int, error) {
        fieldConfigValue, err := c.getFieldConfigValue(fieldOpts)
        if err != nil {
                if !errors.Is(err, errCannotDecodeNonRequiredField) {
                        return 0, err
                }
        }

        var (
                decodedFields int
                decodeErr     error
                fieldDecoder  fieldDecoderFunc
        )

        if commonDecoder := getCommonDecoder(targetValue.Type()); commonDecoder != nil {
                if err := commonDecoder(targetValue, fieldConfigValue); err != nil {
                        if fieldOpts.strict {
                                return 0, fmt.Errorf("error decoding field value: %w", err)
                        }

                        return 0, nil
                }

                return 1, nil
        }

        if targetValue.Kind() == reflect.Ptr {
                dereferencedTargetValue := reflect.New(targetValue.Type().Elem()).Elem()

                decodedFields, err := c.decodeField(dereferencedTargetValue, fieldOpts)
                if err != nil {
                        if fieldOpts.strict {
                                return 0, fmt.Errorf("error decoding pointer value: %w", err)
                        }

                        return 0, nil
                }

                targetValue.Set(dereferencedTargetValue.Addr())

                return decodedFields, nil
        }

        // check if targetValue implements Decoder interface
        if decoder, ok := targetValue.Addr().Interface().(Decoder); ok {
                if err := decoder.Decode(fieldConfigValue); err != nil {
                        return 0, fmt.Errorf("%w: %w", errCannotDecodeCustomTypeField, err)
                }

                return 1, nil
        }

        switch targetValue.Kind() {
        case reflect.Map:
                fieldDecoder = c.decodeMap
        case reflect.Slice:
                fieldDecoder = c.decodeSlice
        case reflect.Struct:
                fieldDecoder = c.decodeStruct
        default:
                fieldDecoder = c.decodePrimitiveType
        }

        decodedFields, decodeErr = fieldDecoder(targetValue, fieldConfigValue, fieldOpts.strict)
        if decodeErr != nil {
                return 0, decodeErr
        }

        return decodedFields, nil
}

func (c *ConfigSet) decodeMap(targetMapValue reflect.Value, configValue any, strict bool) (int, error) {
        var (
                configMapValue     = reflect.ValueOf(configValue)
                targetMapValueType = targetMapValue.Type()
                targetKeyType      = targetMapValueType.Key()
                targetValueType    = targetMapValueType.Elem()
                setFieldCount      = 0
        )

        // setup empty map
        targetMapValue.Set(reflect.MakeMap(targetMapValueType))

        for _, key := range configMapValue.MapKeys() {
                var (
                        k = reflect.New(targetKeyType).Elem()
                        v = reflect.New(targetValueType).Elem()
                )

                // decode map key
                _, err := c.decodePrimitiveType(k, key.Interface(), strict)
                if err != nil {
                        return 0, fmt.Errorf("error decoding map key: %w", err)
                }

                // decode map value
                decodedFieldCount, err := c.subValue(configValue).
                        decodeField(v, fieldOptions{
                                path:         keySegment(key.String()).String(),
                                strict:       strict,
                                required:     false,
                                defaultValue: nil,
                        })
                if err != nil {
                        return 0, fmt.Errorf("error decoding map value: %w", err)
                }

                targetMapValue.SetMapIndex(k, v)

                setFieldCount += decodedFieldCount
        }

        return setFieldCount, nil
}

func (c *ConfigSet) decodeStruct(targetStructValue reflect.Value, configValue any, strict bool) (int, error) {
        var (
                targetStructType = targetStructValue.Type()
                setFieldCount    = 0
        )

        for i := range targetStructValue.NumField() {
                // get the struct field's tag and options
                targetStructFieldOpts := c.readTag(targetStructType.Field(i), c.decoder.tag)

                // get the struct field's reflection value
                targetStructFieldValue := targetStructValue.Field(i)

                // check if the field is exported
                if !targetStructFieldValue.CanSet() || !targetStructFieldValue.Addr().CanInterface() {
                        continue
                }

                // set the field's strictness
                targetStructFieldOpts.strict = strict || targetStructFieldOpts.strict

                // decode the field
                decodedFieldCount, err := c.subValue(configValue).
                        decodeField(targetStructFieldValue, targetStructFieldOpts)
                if err != nil {
                        return 0, fmt.Errorf("error decoding struct field value: %w", err)
                }

                setFieldCount += decodedFieldCount
        }

        return setFieldCount, nil
}

func (c *ConfigSet) decodeSlice(targetSliceValue reflect.Value, configValue any, strict bool) (int, error) {
        var (
                configSliceValue     = reflect.ValueOf(configValue)
                configSliceValueKind = configSliceValue.Kind()
                setFieldCount        = 0
        )

        if configSliceValueKind != reflect.Slice {
                if configSliceValueKind != reflect.String {
                        return 0, fmt.Errorf("%w: %v", errCannotDecodeNonSliceValueToTarget, configSliceValueKind)
                }

                return c.decodeSlice(targetSliceValue, strings.Split(configSliceValue.String(), sliceSplitChar), strict)
        }

        configSliceValueLength := configSliceValue.Len()

        // Set slice to the same length as the config slice
        targetSliceValue.Set(reflect.MakeSlice(targetSliceValue.Type(), configSliceValueLength, configSliceValueLength))

        // Decode each element based on its type
        for i := range configSliceValueLength {
                decodedFieldCount, err := c.subValue(configValue).
                        decodeField(targetSliceValue.Index(i), fieldOptions{
                                path:         indexSegment(i).String(),
                                strict:       strict,
                                required:     false,
                                defaultValue: nil,
                        })
                if err != nil {
                        return setFieldCount, fmt.Errorf("error decoding slice element value: %w", err)
                }

                setFieldCount += decodedFieldCount
        }

        return setFieldCount, nil
}

func (c *ConfigSet) decodePrimitiveType(primitiveValue reflect.Value, configValue any, strict bool) (int, error) {
        primitiveInterface := primitiveValue.Addr().Interface()

        // check if primitive implements encoding.TextUnmarshaler interface
        if unmarshaler, ok := primitiveInterface.(encoding.TextUnmarshaler); ok {
                if err := unmarshaler.UnmarshalText(castToBytes(configValue)); err != nil {
                        return 0, fmt.Errorf("%w: %w", errCannotUnmarshalPrimitive, err)
                }

                primitiveValue.Set(reflect.ValueOf(primitiveInterface).Elem())

                return 1, nil
        }

        // select the appropriate decoder function based on the primitive's kind
        var (
                primitiveDecoderFunc decoderFunc
                primitiveValueKind   = primitiveValue.Kind()
        )

        switch primitiveValueKind {
        case reflect.Bool:
                primitiveDecoderFunc = decodeBool
        case reflect.String:
                primitiveDecoderFunc = decodeString
        case reflect.Float32, reflect.Float64:
                primitiveDecoderFunc = decodeFloat
        case reflect.Int, reflect.Int8, reflect.Int16, reflect.Int32, reflect.Int64:
                primitiveDecoderFunc = decodeInt
        case reflect.Uint, reflect.Uint8, reflect.Uint16, reflect.Uint32, reflect.Uint64:
                primitiveDecoderFunc = decodeUint
        default:
                return 0, fmt.Errorf("%w: %v", errUnsupportedPrimitiveKind, primitiveValueKind)
        }

        if err := primitiveDecoderFunc(primitiveValue, configValue); err != nil {
                if strict {
                        return 0, fmt.Errorf("error decoding primitive value: %w", err)
                }

                return 0, nil
        }

        return 1, nil
}

func (c *ConfigSet) readTag(field reflect.StructField, tag string) fieldOptions {
        fieldOpts := fieldOptions{
                path:         "",
                strict:       false,
                required:     false,
                defaultValue: nil,
        }

        tagValue := field.Tag.Get(tag)
        if tagValue == "" {
                return fieldOpts
        }

        tagParts := strings.Split(tagValue, ",")

        fieldOpts.path = tagParts[0]

        // read the remaining tag parts
        for _, part := range tagParts[1:] {
                if part == "strict" {
                        fieldOpts.strict = true

                        continue
                }

                if part == "required" {
                        fieldOpts.required = true

                        continue
                }

                if strings.HasPrefix(part, "default=") {
                        devaultValue := part[8:]
                        fieldOpts.defaultValue = &devaultValue

                        continue
                }
        }

        return fieldOpts
}

func (c *ConfigSet) subValue(value any) *ConfigSet {
        return &ConfigSet{
                value:   &value,
                decoder: c.decoder,
        }
}

func castToBytes(value any) []byte {
        return []byte(castToString(value))
}

func castToString(value any) string {
        if stringValue, ok := value.(string); ok {
                return stringValue
        }

        return fmt.Sprintf("%v", value)
}

package confiq

import (
        "errors"
        "fmt"
        "maps"
)

const noPrefix = ""

// Collection of loader errors.
var (
        ErrCannotOpenConfig = errors.New("cannot open config")
        ErrCannotLoadConfig = errors.New("cannot load config")
)

var (
        errValueCannotBeNil           = errors.New("value cannot be nil")
        errCannotApplyValueOfThisType = errors.New("cannot apply value of this type")
        errCannotApplyMapValue        = errors.New("cannot apply map value")
        errCannotApplySliceValue      = errors.New("cannot apply slice value")
)

type loader struct {
        prefix string
}

func (c *ConfigSet) Load(valueContainer IValueContainer, options ...loadOption) error {
        if errs := valueContainer.Errors(); len(errs) > 0 {
                return fmt.Errorf("%w: %w", ErrCannotLoadConfig, errors.Join(errs...))
        }

        return c.applyValues(valueContainer.Get(), options...)
}

// LoadRawValue loads a raw value into the config set.
// The value must be a map[string]any or a slice of any.
func (c *ConfigSet) LoadRawValue(newValues []any, options ...loadOption) error {
        if newValues == nil {
                return errValueCannotBeNil
        }

        return c.applyValues(newValues, options...)
}

func newLoader() *loader {
        return &loader{
                prefix: noPrefix,
        }
}

func (c *ConfigSet) applyValues(newValues []any, options ...loadOption) error {
        loader := newLoader()

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

        for _, newValue := range newValues {
                switch v := newValue.(type) {
                case map[string]any:
                        if err := c.applyMap(v, loader.prefix); err != nil {
                                return err
                        }
                case []any:
                        if err := c.applySlice(v, loader.prefix); err != nil {
                                return err
                        }
                default:
                        return fmt.Errorf("%w: %T", errCannotApplyValueOfThisType, newValue)
                }
        }

        return nil
}

func (c *ConfigSet) applyMap(newValue map[string]any, prefix string) error {
        if prefix == "" {
                return c.applyMapWithoutPrefix(newValue)
        }

        return c.applyMapWithPrefix(newValue, prefix)
}

func (c *ConfigSet) applySlice(newValue []any, prefix string) error {
        if prefix == "" {
                return c.applySliceWithoutPrefix(newValue)
        }

        return c.applySliceWithPrefix(newValue, prefix)
}

func (c *ConfigSet) applyMapWithoutPrefix(newValue map[string]any) error {
        if *c.value == nil {
                *c.value = newValue

                return nil
        }

        valueMap, ok := (*c.value).(map[string]any)
        if !ok {
                return errCannotApplyMapValue
        }

        maps.Copy(valueMap, newValue)

        return nil
}

func (c *ConfigSet) applyMapWithPrefix(newValue map[string]any, prefix string) error {
        if *c.value == nil {
                *c.value = map[string]any{}
        }

        valueMap, ok := (*c.value).(map[string]any)
        if !ok {
                return errCannotApplyMapValue
        }

        valueMapAtPath, ok := valueMap[prefix]
        if !ok {
                valueMap[prefix] = newValue

                return nil
        }

        valueMapAtPathMap, ok := valueMapAtPath.(map[string]any)
        if !ok {
                return errCannotApplyMapValue
        }

        maps.Copy(valueMapAtPathMap, newValue)

        return nil
}

func (c *ConfigSet) applySliceWithoutPrefix(newValue []any) error {
        if *c.value == nil {
                *c.value = newValue

                return nil
        }

        valueSlice, ok := (*c.value).([]any)
        if !ok {
                return errCannotApplySliceValue
        }

        valueSlice = append(valueSlice, newValue...)

        *c.value = valueSlice

        return nil
}

func (c *ConfigSet) applySliceWithPrefix(newValue []any, prefix string) error {
        if *c.value == nil {
                *c.value = map[string]any{}
        }

        valueMap, ok := (*c.value).(map[string]any)
        if !ok {
                return errCannotApplySliceValue
        }

        valueMapAtPath, ok := valueMap[prefix]
        if !ok {
                valueMap[prefix] = newValue

                return nil
        }

        valueMapAtPathSlice, ok := valueMapAtPath.([]any)
        if !ok {
                return errCannotApplySliceValue
        }

        valueMapAtPathSlice = append(valueMapAtPathSlice, newValue...)

        valueMap[prefix] = valueMapAtPathSlice

        return nil
}

// Package confiqenv allows confiq values to be loaded from Env format.
package confiqenv

import (
        "bytes"
        "errors"
        "fmt"
        "io"
        "os"
        "path/filepath"
        "strings"

        "github.com/hashicorp/go-envparse"
)

const (
        envSplitChar     = "="
        envSplitElements = 2
)

var (
        ErrCannotGetBytesFromReader = errors.New("cannot get bytes from reader")
        ErrCannotOpenEnvFile        = errors.New("cannot open Env file")
        ErrCannotReadEnvData        = errors.New("cannot read Env data")
)

// Container is a struct that holds the loaded values.
type Container struct {
        values []any
        errors []error
}

// Get returns the loaded JSON values.
func (c *Container) Get() []any {
        return c.values
}

// Errors returns the errors that occurred during the loading process.
func (c *Container) Errors() []error {
        return c.errors
}

// Load creates an empty container, into which the JSON values can be loaded.
func Load() *Container {
        container := new(Container)

        return container
}

// FromEnvironment loads config data from the environment variables.
func (c *Container) FromEnvironment() *Container {
        var (
                envSlice = os.Environ()
                envMap   = make(map[string]any)
        )

        for _, envElement := range envSlice {
                envKeyValue := strings.SplitN(envElement, envSplitChar, envSplitElements)

                envMap[envKeyValue[0]] = envKeyValue[1]
        }

        c.values = append(c.values, envMap)

        return nil
}

// FromFile loads a Env file from the given path.
func (c *Container) FromFile(path string) *Container {
        inputBytes, err := os.ReadFile(filepath.Clean(path))
        if err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotOpenEnvFile, err))

                return c
        }

        return c.FromBytes(inputBytes)
}

// FromString loads a Env file from the given string.
func (c *Container) FromString(input string) *Container {
        return c.FromBytes([]byte(input))
}

// FromBytes loads a Env file from the given bytes.
func (c *Container) FromBytes(input []byte) *Container {
        return c.FromReader(bytes.NewReader(input))
}

// FromReader loads a Env file from a reader stream.
func (c *Container) FromReader(reader io.Reader) *Container {
        if reader == nil {
                c.errors = append(c.errors, ErrCannotReadEnvData)

                return c
        }

        parsedEnvMap, err := envparse.Parse(reader)
        if err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotReadEnvData, err))

                return c
        }

        c.values = append(c.values, envMapAsAny(parsedEnvMap))

        return c
}

func envMapAsAny(envMap map[string]string) map[string]any {
        anyMap := make(map[string]any)

        for key, value := range envMap {
                anyMap[key] = value
        }

        return anyMap
}

// Package confiqjson allows confiq values to be loaded from JSON format.
package confiqjson

import (
        "bytes"
        "encoding/json"
        "errors"
        "fmt"
        "io"
        "os"
        "path/filepath"
)

var (
        ErrCannotOpenJSONFile  = errors.New("cannot open JSON file")
        ErrCannotReadJSONData  = errors.New("cannot read JSON data")
        ErrCannotReadJSONBytes = errors.New("cannot read JSON bytes")
)

// Container is a struct that holds the loaded values.
type Container struct {
        values []any
        errors []error
}

// Get returns the loaded JSON values.
func (c *Container) Get() []any {
        return c.values
}

// Errors returns the errors that occurred during the loading process.
func (c *Container) Errors() []error {
        return c.errors
}

// Load creates an empty container, into which the JSON values can be loaded.
func Load() *Container {
        container := new(Container)

        return container
}

// FromFile loads a JSON file from the given path.
func (c *Container) FromFile(path string) *Container {
        bytes, err := os.ReadFile(filepath.Clean(path))
        if err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotOpenJSONFile, err))

                return c
        }

        c.readFromBytes(bytes)

        return c
}

// FromString loads a JSON file from the given string.
func (c *Container) FromString(input string) *Container {
        c.readFromBytes([]byte(input))

        return c
}

// FromReader loads a JSON file from a reader stream.
func (c *Container) FromReader(reader io.Reader) *Container {
        if reader == nil {
                c.errors = append(c.errors, ErrCannotReadJSONData)

                return c
        }

        buffer := new(bytes.Buffer)

        if _, err := buffer.ReadFrom(reader); err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotReadJSONData, err))

                return c
        }

        c.readFromBytes(buffer.Bytes())

        return c
}

// FromBytes loads a JSON file from the given bytes.
func (c *Container) FromBytes(input []byte) *Container {
        c.readFromBytes(input)

        return c
}

func (c *Container) readFromBytes(input []byte) {
        var value any

        if err := json.Unmarshal(input, &value); err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotReadJSONBytes, err))

                return
        }

        c.values = append(c.values, value)
}

// Package confiqtoml allows confiq values to be loaded from TOML format.
package confiqtoml

import (
        "bytes"
        "errors"
        "fmt"
        "io"
        "os"
        "path/filepath"

        "github.com/pelletier/go-toml"
)

var (
        ErrCannotOpenTOMLFile  = errors.New("cannot open TOML file")
        ErrCannotReadTOMLData  = errors.New("cannot read TOML data")
        ErrCannotReadTOMLBytes = errors.New("cannot read TOML bytes")
)

// Container is a struct that holds the loaded values.
type Container struct {
        values []any
        errors []error
}

// Get returns the loaded TOML values.
func (c *Container) Get() []any {
        return c.values
}

// Errors returns the errors that occurred during the loading process.
func (c *Container) Errors() []error {
        return c.errors
}

// Load creates an empty container, into which the TOML values can be loaded.
func Load() *Container {
        container := new(Container)

        return container
}

// FromFile loads a TOML file from the given path.
func (c *Container) FromFile(path string) *Container {
        bytes, err := os.ReadFile(filepath.Clean(path))
        if err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotOpenTOMLFile, err))

                return c
        }

        c.readFromBytes(bytes)

        return c
}

// FromString loads a TOML file from the given string.
func (c *Container) FromString(input string) *Container {
        c.readFromBytes([]byte(input))

        return c
}

// FromReader loads a TOML file from a reader stream.
func (c *Container) FromReader(reader io.Reader) *Container {
        if reader == nil {
                c.errors = append(c.errors, ErrCannotReadTOMLData)

                return c
        }

        buffer := new(bytes.Buffer)

        if _, err := buffer.ReadFrom(reader); err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotReadTOMLData, err))

                return c
        }

        c.readFromBytes(buffer.Bytes())

        return c
}

// FromBytes loads a TOML file from the given bytes.
func (c *Container) FromBytes(input []byte) *Container {
        c.readFromBytes(input)

        return c
}

func (c *Container) readFromBytes(input []byte) {
        var value any

        if err := toml.Unmarshal(input, &value); err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotReadTOMLBytes, err))

                return
        }

        c.values = append(c.values, value)
}

// Package confiqyaml allows confiq values to be loaded from YAML format.
package confiqyaml

import (
        "bytes"
        "errors"
        "fmt"
        "io"
        "os"
        "path/filepath"

        "gopkg.in/yaml.v3"
)

var (
        ErrCannotOpenYAMLFile  = errors.New("cannot open YAML file")
        ErrCannotReadYAMLData  = errors.New("cannot read YAML data")
        ErrCannotReadYAMLBytes = errors.New("cannot read YAML bytes")
)

// Container is a struct that holds the loaded values.
type Container struct {
        values []any
        errors []error
}

// Get returns the loaded YAML values.
func (c *Container) Get() []any {
        return c.values
}

// Errors returns the errors that occurred during the loading process.
func (c *Container) Errors() []error {
        return c.errors
}

// Load creates an empty container, into which the YAML values can be loaded.
func Load() *Container {
        container := new(Container)

        return container
}

// FromFile loads a YAML file from the given path.
func (c *Container) FromFile(path string) *Container {
        bytes, err := os.ReadFile(filepath.Clean(path))
        if err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotOpenYAMLFile, err))

                return c
        }

        c.readFromBytes(bytes)

        return c
}

// FromString loads a YAML file from the given string.
func (c *Container) FromString(input string) *Container {
        c.readFromBytes([]byte(input))

        return c
}

// FromReader loads a YAML file from a reader stream.
func (c *Container) FromReader(reader io.Reader) *Container {
        if reader == nil {
                c.errors = append(c.errors, ErrCannotReadYAMLData)

                return c
        }

        buffer := new(bytes.Buffer)

        if _, err := buffer.ReadFrom(reader); err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotReadYAMLData, err))

                return c
        }

        c.readFromBytes(buffer.Bytes())

        return c
}

// FromBytes loads a YAML file from the given bytes.
func (c *Container) FromBytes(input []byte) *Container {
        c.readFromBytes(input)

        return c
}

func (c *Container) readFromBytes(input []byte) {
        var value any

        if err := yaml.Unmarshal(input, &value); err != nil {
                c.errors = append(c.errors, fmt.Errorf("%w: %w", ErrCannotReadYAMLBytes, err))

                return
        }

        c.values = append(c.values, value)
}

package confiq

// ConfigSetOptions is exposed so that functions which wrap the New function can make adding the WithTag option easier.
type ConfigSetOptions []loadOption

type configSetOption func(*ConfigSet)

// WithTag sets the struct tag to be used by the decoder for reading configuration values of struct fields.
func WithTag(tag string) configSetOption {
        return func(s *ConfigSet) {
                s.decoder.tag = tag
        }
}

// LoadOptions is exposed so that functions which wrap the Load function can make adding the WithPrefix option easier.
type LoadOptions []loadOption

type loadOption func(*loader)

// WithPrefix sets the prefix to be used when loading configuration values into the ConfigSet.
func WithPrefix(prefix string) loadOption {
        return func(l *loader) {
                l.prefix = prefix
        }
}

// DecodeOptions is exposed so that functions which wrap the Decode function can make adding the AsStrict and FromPrefix options easier.
type DecodeOptions []decodeOption

type decodeOption func(*decodeSettings)

// AsStrict sets the decoder to decode the configuration values as if all fields are set to strict.
func AsStrict() decodeOption {
        return func(d *decodeSettings) {
                d.strict = true
        }
}

// FromPrefix sets the prefix to be used when decoding configuration values into the target struct.
func FromPrefix(prefix string) decodeOption {
        return func(d *decodeSettings) {
                d.prefix = prefix
        }
}

package confiq

import (
        "errors"
        "fmt"
        "reflect"
        "strconv"
)

var (
        errCannotParseBool  = errors.New("cannot parse bool")
        errCannotParseFloat = errors.New("cannot parse float")
        errCannotParseInt   = errors.New("cannot parse int")
        errCannotParseUint  = errors.New("cannot parse uint")
)

func decodeString(targetValue reflect.Value, sourceValue any) error {
        targetValue.SetString(castToString(sourceValue))

        return nil
}

func decodeBool(targetValue reflect.Value, sourceValue any) error {
        if boolValue, ok := sourceValue.(bool); ok {
                targetValue.SetBool(boolValue)

                return nil
        } else {
                parsedBool, err := strconv.ParseBool(castToString(sourceValue))
                if err != nil {
                        return fmt.Errorf("%w: %w", errCannotParseBool, err)
                }

                targetValue.SetBool(parsedBool)
        }

        return nil
}

func decodeFloat(targetValue reflect.Value, sourceValue any) error {
        switch sV := sourceValue.(type) {
        case float32:
                targetValue.SetFloat(float64(sV))
        case float64:
                targetValue.SetFloat(sV)
        default:
                parsedFloat, err := strconv.ParseFloat(castToString(sourceValue), targetValue.Type().Bits())
                if err != nil {
                        return fmt.Errorf("%w: %w", errCannotParseFloat, err)
                }

                targetValue.SetFloat(parsedFloat)
        }

        return nil
}

func decodeInt(targetValue reflect.Value, sourceValue any) error {
        switch sV := sourceValue.(type) {
        case int:
                targetValue.SetInt(int64(sV))
        case int8:
                targetValue.SetInt(int64(sV))
        case int16:
                targetValue.SetInt(int64(sV))
        case int32:
                targetValue.SetInt(int64(sV))
        case int64:
                targetValue.SetInt(sV)
        default:
                parsedInt, err := strconv.ParseInt(castToString(sourceValue), 0, targetValue.Type().Bits())
                if err != nil {
                        return fmt.Errorf("%w: %w", errCannotParseInt, err)
                }

                targetValue.SetInt(parsedInt)
        }

        return nil
}

func decodeUint(targetValue reflect.Value, sourceValue any) error {
        switch sV := sourceValue.(type) {
        case uint:
                targetValue.SetUint(uint64(sV))
        case uint8:
                targetValue.SetUint(uint64(sV))
        case uint16:
                targetValue.SetUint(uint64(sV))
        case uint32:
                targetValue.SetUint(uint64(sV))
        case uint64:
                targetValue.SetUint(sV)
        default:
                parsedUint, err := strconv.ParseUint(castToString(sourceValue), 0, targetValue.Type().Bits())
                if err != nil {
                        return fmt.Errorf("%w: %w", errCannotParseUint, err)
                }

                targetValue.SetUint(parsedUint)
        }

        return nil
}

package confiq

import (
        "strconv"
        "strings"
)

const (
        segmentDividerChar = "."
        openBraceChar      = "["
        closeBraceChar     = "]"
)

type segment interface {
        String() string
}

type keySegment string

func (kS keySegment) String() string {
        return string(kS)
}

func (kS keySegment) asString() string {
        return string(kS)
}

type indexSegment int

func (iS indexSegment) String() string {
        return openBraceChar + strconv.Itoa(int(iS)) + closeBraceChar
}

func (iS indexSegment) asInt() int {
        return int(iS)
}

func getNextSegment(path string) (segment, string) {
        var (
                nextSegment, remainingPath string
                segmentDividerIndex        = strings.Index(path, segmentDividerChar)
        )

        if segmentDividerIndex == -1 {
                nextSegment = path
                remainingPath = ""
        } else {
                nextSegment = path[:segmentDividerIndex]
                remainingPath = path[segmentDividerIndex+1:]
        }

        openBraceIndex := strings.Index(path, openBraceChar)
        if openBraceIndex == -1 {
                return keySegment(nextSegment), remainingPath
        }

        closeBraceIndex := strings.Index(nextSegment, closeBraceChar)
        if closeBraceIndex == -1 || closeBraceIndex < openBraceIndex {
                return keySegment(nextSegment), remainingPath
        }

        if openBraceIndex != 0 {
                return keySegment(nextSegment[:openBraceIndex]), nextSegment[openBraceIndex:closeBraceIndex+1] + segmentDividerChar + remainingPath
        }

        index := nextSegment[openBraceIndex+1 : closeBraceIndex]

        if indexInt, err := strconv.Atoi(index); err == nil {
                return indexSegment(indexInt), remainingPath
        }

        return keySegment(index), remainingPath
}