// Copyright 2023 GoEdge CDN goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cn .

package main

import (
	"encoding/json"
	"fmt"
	"github.com/TeaOSLab/EdgeCommon/pkg/langs"
	"github.com/iwind/TeaGo/Tea"
	_ "github.com/iwind/TeaGo/bootstrap"
	"github.com/iwind/TeaGo/lists"
	"github.com/iwind/TeaGo/types"
	"go/format"
	"os"
	"path/filepath"
	"regexp"
	"sort"
	"strconv"
	"strings"
)

func main() {
	var args = os.Args
	if len(args) >= 2 {
		switch args[1] {
		case "generate":
			runGenerate()
		}
	} else {
		fmt.Println("Usage: langs [generate]")
	}
}

func runGenerate() {
	var rootDir = filepath.Clean(Tea.Root + "/../pkg/langs/protos")
	dir, err := os.Open(rootDir)
	if err != nil {
		fmt.Println("[ERROR]read dir failed: " + err.Error())
		return
	}
	defer func() {
		_ = dir.Close()
	}()

	files, err := dir.Readdir(0)
	if err != nil {
		fmt.Println("[ERROR]read dir failed: " + err.Error())
		return
	}

	var dirRegexp = regexp.MustCompile(`^[a-z]+-[a-z]+$`)
	var jsonFileNameRegexp = regexp.MustCompile(`^([a-zA-Z0-9]+)(_([a-zA-Z0-9]+))+\.json$`)
	var messageCodeRegexp = regexp.MustCompile(`^[a-zA-Z0-9_]+$`)

	var messageCodes = []string{}
	var messageMaps = map[string]map[string]string{} // lang => { K:V }
	var defaultLang = langs.DefaultManager().DefaultLang()

	for _, file := range files {
		var dirName = file.Name()

		if !file.IsDir() || !dirRegexp.MatchString(dirName) {
			continue
		}
		var langCode = dirName
		var isBaseLang = langCode == defaultLang

		func() {
			jsonFiles, err := filepath.Glob(rootDir + "/" + dirName + "/*.json")
			if err != nil {
				fmt.Println("[ERROR]list json files failed: " + err.Error())
				return
			}

			for _, jsonFile := range jsonFiles {
				var jsonFileName = filepath.Base(jsonFile)
				if len(jsonFileName) == 0 || !jsonFileNameRegexp.MatchString(jsonFileName) {
					continue
				}
				var module = strings.TrimSuffix(jsonFileName, ".json")

				data, err := os.ReadFile(jsonFile)
				if err != nil {
					fmt.Println("[ERROR]read json file '" + jsonFile + "' failed: " + err.Error())
					return
				}

				var m = map[string]string{} // code => value
				err = json.Unmarshal(data, &m)
				if err != nil {
					fmt.Println("[ERROR]decode json file '" + jsonFile + "' failed: " + err.Error())
					return
				}

				var newM = map[string]string{}
				for code, value := range m {
					if !messageCodeRegexp.MatchString(code) {
						fmt.Println("[ERROR]invalid message code '" + code + "'")
						return
					}

					var fullCode = module + "_" + code
					if isBaseLang {
						messageCodes = append(messageCodes, fullCode)
					}
					newM[fullCode] = value
				}

				finalMap, ok := messageMaps[langCode]
				if !ok {
					finalMap = map[string]string{}
					messageMaps[langCode] = finalMap
				}
				for code, value := range newM {
					finalMap[code] = value
				}
			}
		}()
	}

	// check message codes
	fmt.Println("checking message codes ...")
	var defaultMessageMap = map[string]string{}
	for langCode, messageMap := range messageMaps {
		if langCode == defaultLang { // only check lang not equal to 'en-us'
			defaultMessageMap = messageMap
			continue
		}

		for messageCode := range messageMap {
			if !lists.ContainsString(messageCodes, messageCode) {
				fmt.Println("[ERROR]message code '" + messageCode + "' in lang '" + langCode + "' not exist in default lang file ('" + defaultLang + "')")
				return
			}
		}
	}
	fmt.Println("found '" + types.String(len(messageCodes)) + "' message codes")

	// generate codes/codes.go
	sort.Strings(messageCodes)
	var codesSource = `
// generated by run 'langs generate'

package codes

import(
	"github.com/TeaOSLab/EdgeCommon/pkg/langs"
)

const (
	`

	for _, messageCode := range messageCodes {
		// add comment to message code
		comment, _, _ := strings.Cut(defaultMessageMap[messageCode], "\n")

		codesSource += upperWords(messageCode) + " langs.MessageCode = " + strconv.Quote(messageCode) + " // " + comment + "\n"
	}

	codesSource += `
)
`

	formattedCodesSource, err := format.Source([]byte(codesSource))
	if err != nil {
		fmt.Println("[ERROR]format 'codes.go' failed: " + err.Error())
		return
	}

	fmt.Println("generating 'codes/codes.go' ...")
	err = os.WriteFile(Tea.Root+"/../pkg/langs/codes/codes.go", formattedCodesSource, 0666)
	if err != nil {
		fmt.Println("[ERROR]write to 'codes.go' failed: " + err.Error())
		return
	}

	// generate messages_LANG.go
	for langCode, messageMap := range messageMaps {
		var langFile = strings.ReplaceAll("messages/messages_"+langCode+".go", "-", "_")

		fmt.Println("generating '" + langFile + "' ...")
		var source = `
// generated by run 'langs generate'

package messages

import(
	"github.com/TeaOSLab/EdgeCommon/pkg/langs"
)

func init() {
	langs.Load("` + langCode + `", map[string]string{
	`

		for code, value := range messageMap {
			source += strconv.Quote(code) + ": " + strconv.Quote(value) + ",\n"
		}

		source += `
	})
}
`

		formattedSource, err := format.Source([]byte(source))
		if err != nil {
			fmt.Println("[ERROR]format '" + langFile + "' failed: " + err.Error())
			return
		}

		err = os.WriteFile(Tea.Root+"/../pkg/langs/"+langFile, formattedSource, 0666)
		if err != nil {
			fmt.Println("[ERROR]write file '" + langFile + "' failed: " + err.Error())
			return
		}
	}

	// generate language javascript files for EdgeAdmin
	for lang, messageMap := range messageMaps {
		if lang != defaultLang {
			// TODO merge messageMap with default message map
		}

		for _, component := range []string{"EdgeAdmin", "EdgeUser"} {
			fmt.Println("generating '" + lang + ".js' for " + component + " ...")
			var targetFile = filepath.Clean(Tea.Root + "/../../" + component + "/web/public/js/langs/" + lang + ".js")
			var targetDir = filepath.Dir(targetFile)
			dirStat, _ := os.Stat(targetDir)
			if dirStat != nil {
				messageMapJSON, err := json.Marshal(messageMap)
				if err != nil {
					fmt.Println("[ERROR]marshal message map failed: " + err.Error())
					return
				}
				err = os.WriteFile(targetFile, []byte(`// generated by 'langs generate'
window.LANG_MESSAGES = `+string(messageMapJSON)+";\n"), 0666)
				if err != nil {
					fmt.Println("[ERROR]write file '" + targetFile + "' failed: " + err.Error())
					return
				}
			}
		}
	}

	fmt.Println("success")
}

func upperWords(s string) string {
	var words = strings.Split(s, "_")
	for index, word := range words {
		words[index] = upperWord(word)
	}
	return strings.Join(words, "")
}

func upperWord(word string) string {
	var l = len(word)
	if l == 0 {
		return ""
	}

	if l == 1 {
		return strings.ToUpper(word)
	}

	// special words
	switch word {
	case "api", "http", "https", "tcp", "udp", "ip", "dns", "ns", "waf", "acme", "ssh", "toa":
		return strings.ToUpper(word)
	case "ipv6":
		return "IPv6"
	case "ddos":
		return "DDoS"
	}

	return strings.ToUpper(word[:1]) + word[1:]
}