package pinyin

import (
	"bufio"
	"fmt"
	"os"
	"strconv"
	"strings"
	"unicode/utf8"
)

type vowel int32

var (
	ys = []vowel{'ā', 'ē', 'ī', 'ō', 'ū', 'ǖ', 'Ā', 'Ē', 'Ī', 'Ō', 'Ū', 'Ǖ'} // 单韵母 一声
	es = []vowel{'á', 'é', 'í', 'ó', 'ú', 'ǘ', 'Á', 'É', 'Í', 'Ó', 'Ú', 'Ǘ'} // 单韵母 二声
	ss = []vowel{'ǎ', 'ě', 'ǐ', 'ǒ', 'ǔ', 'ǚ', 'Ǎ', 'Ě', 'Ǐ', 'Ǒ', 'Ǔ', 'Ǚ'} // 单韵母 三声
	fs = []vowel{'à', 'è', 'ì', 'ò', 'ù', 'ǜ', 'À', 'È', 'Ì', 'Ò', 'Ù', 'Ǜ'} // 单韵母 四声
	ws = []vowel{'a', 'e', 'i', 'o', 'u', 'v', 'A', 'E', 'I', 'O', 'U', 'V'} // 单韵母 无声调
)

var (
	pinyinTemp map[vowel]interface{}
	toneTemp   map[vowel]vowel
)

const (
	Tone               string = "带声调的拼音"    // 带声调的拼音 例如：Cào
	InitialsInCapitals string = "首字母大写不带声调" // 首字母大写不带声调 例如：Cao
	None               string = ""          //如果匹配不到汉字，就靠大家维护下 【匹配失败，手动添加代码到pinyin.txt】
)

func LoadingPYFile(filename string) {
	f, err := os.Open(filename)
	if err != nil {
		fmt.Println(err)
	}
	if err != nil {
		panic(err)
	}
	pinyinTemp = make(map[vowel]interface{}, 0)
	toneTemp = make(map[vowel]vowel)
	for i, t := range ys {
		toneTemp[t] = ws[i]
	}
	for i, t := range es {
		toneTemp[t] = ws[i]
	}
	for i, t := range ss {
		toneTemp[t] = ws[i]
	}
	for i, t := range fs {
		toneTemp[t] = ws[i]
	}
	defer func() {
		_ = f.Close()
	}()
	scanner := bufio.NewScanner(f)
	for scanner.Scan() {
		//单行分割取出拼音
		str := strings.Split(scanner.Text(), "=>")
		if len(str) < 2 {
			continue
		}
		i, err := strconv.ParseInt(str[0], 16, 32)
		if err != nil {
			continue
		}
		pinyinTemp[vowel(i)] = str[1]
		//fmt.Println(pinyinTemp[vowel(i)])
	}
}

func PY(source string) (string, error) {
	return PYSplit(source, "", "")
}

func PYSplit(source string, split string, types string) (string, error) {
	hz := []vowel(source)
	words := make([]string, 0)
	for _, s := range hz {
		word, err := _vowel(s, types)
		if err != nil {
			return None, err
		}
		if len(word) > 0 {
			words = append(words, word)
		}
	}
	return strings.Join(words, split), nil
}

func _vowel(source vowel, types string) (string, error) {
	switch types {
	case Tone:
		return getTone(source), nil
	case InitialsInCapitals:
		return getInitialsInCapitals(source), nil
	default:
		return getDefault(source), nil
	}
}

func getTone(source vowel) string {
	if pinyinTemp[source] != nil {
		return pinyinTemp[source].(string)
	}
	return string(source)
}

func getInitialsInCapitals(source vowel) string {
	def := getDefault(source)
	var result string
	if def == "" {
		return def
	}
	str := []vowel(def)
	if str[0] > 32 {
		str[0] = str[0] - 32
	}
	for _, v := range str {
		result += string(v)
	}
	return result
}

func getDefault(source vowel) string {
	tone := getTone(source)
	var result string
	if tone == "" {
		return None
	}
	resultLen := make([]vowel, utf8.RuneCountInString(tone))
	count := 0
	for _, t := range tone {
		changes, ok := toneTemp[vowel(t)]
		if ok {
			resultLen[count] = changes
		} else {
			resultLen[count] = vowel(t)
		}
		count++
	}
	for _, v := range resultLen {
		result += string(v)
	}
	return result
}