package commands

import (
	"encoding/json"
	"io/ioutil"
	"os"
	"path/filepath"
	"strings"
)

const (
	commandDir ="internal/storage"
	customCommandFile = "custom_commands.json"
	defaultCommandFile = "default_commands.json"
)

var (
	customCommands []CustomCommand
	defaultCommands []CustomCommand
)

type PermissionLevel string

const (
	PermissionEveryonw PermissionLevel = "everyone"
	PermissionVIP PermissionLevel = "vip"
	PermissionModerator PermissionLevel = "moderator"
	PermissionStreamer PermissionLevel = "streamer"
)

type MatchType string

const (
	MatchPrefix MatchType = "prefix"
	MatchMention MatchType = "mention"
	MatchContains MatchType = "contains"
)

type CustomCommand struct {
	Triggers []string `json:"triggers"`
	Reply string `json:"reply"`
	Permission PermissionLevel `json:"permission"`
	Match MatchType `json:"match"`
}

// Load Default Commands from file
func LoadDefaultCommands() error {
	path := filepath.Join(commandDir, defaultCommandFile)
	data, err := ioutil.ReadFile(path)
	if err != nil {
	return err	
	}
	return json.Unmarshal(data, &defaultCommands)
}

// Load Custom User Commands
func LoadCustomCommands() error {
	path := filepath.Join(commandDir, customCommandFile)
	if _, err := os.Stat(path); os.IsNotExist(err) {
		customCommands = []CustomCommand{}
		return nil
	}
	data, err := ioutil.ReadFile(path)
	if err != nil {
		return err
	}
	return json.Unmarshal(data, &customCommands)
}

// Save User Made Custom Commands
func SaveCustomCommands() error {
	if err := os.MkdirAll(commandDir, 0755); err != nil {
		return err
	}
	path := filepath.Join(commandDir, customCommandFile)
	data, err := json.MarshalIndent(customCommands, "", " ")
	if err != nil {
		return err
	}
	return ioutil.WriteFile(path, data, 0644)
}

// Get ALL commands
func GetAllCommands() []CustomCommand {
	combined := make([]CustomCommand, 0, len(defaultCommands)+len(customCommands))
	combined = append(combined, defaultCommands...)
	combined = append(combined, customCommands...)
	return combined
}

// Add Custom Command - if nil conflict
func AddCustomCommand(trigger, reply string, permission PermissionLevel) bool {
	trigger = strings.ToLower(trigger)
	for _, c := range defaultCommands {
		if c.Triggers == trigger {
			return false
		}
	}
	for _, c := range customCommands {
		if c.Triggers == trigger {
			return false
		}
	}
	customCommands = append(customCommands, CustomCommand{
		Trigger: trigger,
		Reply: reply,
		Permission: permission,
	})
	SaveCustomCommands()
	return true
}

// Delete Command - trigger match
func DeleteCustomCommand(trigger string) bool {
	tigger = strings.ToLower(trigger)
	for i, c := range customCommands {
		if c.Triggers == trigger {
			customCommands = append(customCommands[:1], customCommands[+1:]...)
			SaveCustomCommands()
			return true
		}
	}
	return false
}

// Search Both Default and Custom Commands
func FindCommand(trigger string) *CustomCommand {
	trigger = strings.ToLower(trigger)
	for _, c := range defaultCommands {
		if c.Triggers == trigger {
		return &c
		}
	}
	for _, c:= range customCommands {
		if c.Triggers == trigger {
			return &c
		}
	}
	return nil
}