package cli

import (
	"fmt"
	"slices"
	"strings"
)

type cliOptionBase struct {
	name             string
	shortAlias       string
	aliases          []string
	description      string
	isArray          bool
	hidden           bool
	specialValues    map[string]SpecialValueFunc
	incompatibleWith []string
}

func (opt *cliOptionBase) getBase() *cliOptionBase {
	return opt
}

func (opt *cliOptionBase) getTargetVar() (any, string) {
	return nil, "n/a"
}

func (opt *cliOptionBase) Is(name string) (result bool) {
	if result = opt.name == name; !result && len(opt.aliases) > 0 {
		result = slices.Contains(opt.aliases, name)
	}
	return
}

func (opt *cliOptionBase) isHidden() bool {
	return opt.hidden
}

func (opt *cliOptionBase) SetHidden(hidden bool) {
	opt.hidden = hidden
}

func (opt *cliOptionBase) AddSpecialValue(cliValue string, specialFunc SpecialValueFunc) {
	if opt.specialValues == nil {
		opt.specialValues = make(map[string]SpecialValueFunc)
	}
	opt.specialValues[cliValue] = specialFunc
}

func (opt *cliOptionBase) getSpecialFunc(cliValue string) (specialFunc SpecialValueFunc, exists bool) {
	if len(opt.specialValues) > 0 {
		specialFunc, exists = opt.specialValues[cliValue]
	}
	return
}

func (opt *cliOptionBase) isSet() bool {
	return false
}

func (opt *cliOptionBase) requiresValue() bool {
	return true
}

func (opt *cliOptionBase) addIncompatibleOption(names ...string) {
	opt.incompatibleWith = append(opt.incompatibleWith, names...)
}

func (opt *cliOptionBase) parse(parser cliParser, valuePtr *string) (err error) {
	return fmt.Errorf("unhandled option %q", opt.name)
}

func (opt *cliOptionBase) getDefaultValue() string {
	return ""
}

func pluralSuffix(word string) (suffix string) {
	if len(word) > 0 {
		if strings.HasSuffix(word, "x") || strings.HasSuffix(word, "s") || strings.HasSuffix(word, "ch") {
			suffix = "es"
		} else {
			suffix = "s"
		}
	}
	return
}

func makePlural(word string) (plural string) {
	return word + pluralSuffix(word)
}

func (opt *cliOptionBase) makeOptTemplate(isArray bool, valueType string) (templ string) {
	var suffix, multiValue string
	if isArray {
		suffix = "(" + pluralSuffix(opt.name) + ")"
		multiValue = `["," ...]`
	}
	if opt.shortAlias != "" {
		templ = fmt.Sprintf(`-%s, --%s%s <%s>%s`, opt.shortAlias, opt.name, suffix, valueType, multiValue)
	} else {
		templ = fmt.Sprintf(`--%s%s <%s>%s`, opt.name, suffix, valueType, multiValue)
	}
	return
}

func (opt *cliOptionBase) makeOptSimpleTemplate(valueRequired, multiValue bool, valueType string) (templ string) {
	var valueSpec, dots string

	if multiValue {
		dots = " ..."
	}
	if len(valueType) > 0 {
		valueSpec = " <" + valueType + ">" + dots
		if !valueRequired {
			valueSpec = " [" + valueSpec[1:] + "]"
		}
	}

	if opt.shortAlias != "" {
		templ = fmt.Sprintf(`-%s, --%s%s`, opt.shortAlias, opt.name, valueSpec)
	} else {
		templ = fmt.Sprintf(`--%s%s`, opt.name, valueSpec)
	}
	return
}

func (opt *cliOptionBase) getSpecialValue(parser cliParser, value string, targetVar any) (boxedValue any, err error) {
	if specialFunc, exists := opt.getSpecialFunc(value); exists {
		manager := parser.(OptManager)
		boxedValue, err = specialFunc(manager, value, targetVar)
	}
	return
}

func (opt *cliOptionBase) fetchOptionValue(parser cliParser, argIndex int, valuePtr *string) (value string, skipNextArg bool, err error) {
	if valuePtr != nil {
		value = *valuePtr
	} else {
		if source, optionPresent := parser.getOptionValue(argIndex); optionPresent {
			skipNextArg = true
			value = source
		} else {
			err = errMissingOptionValue(opt.name)
		}
	}
	return
}