package utils

import (
	"bytes"
	"crypto/md5"
	"encoding/hex"
	"encoding/json"
	"fmt"
	"io"
	"math/rand"
	"net/http"
	"strings"
	"time"
)

// UnixToDate 10位时间戳转日期字符串
func UnixToDate(timestamp int) string {
	return time.Unix(int64(timestamp), 0).Format("2006-01-02 15:04:05")
}

// DateToUnix 日期字符串转10位时间戳
func DateToUnix(str string) int64 {
	t, err := time.ParseInLocation("2006-01-02 15:04:05", str, time.Local)
	if err != nil {
		return 0
	}
	return t.Unix()
}

// GetUnixTimestamp 获取10位时间戳
func GetUnixTimestamp() int64 {
	return time.Now().Unix()
}

// GetUnixNano 获取13位时间戳
func GetUnixNano() int64 {
	return time.Now().UnixNano() / 1e6
}

// GetDate 获取当前日期时间字符串
func GetDate() string {
	return time.Now().Format("2006-01-02 15:04:05")
}

// Md5 MD5加密
func Md5(str string) string {
	m := md5.New()
	m.Write([]byte(str))
	return hex.EncodeToString(m.Sum(nil))
}

// 邀请码生成常量
const (
	inviteCodeBase    = "E8S2DZX9WYLTN6BQF7CP5IK3MJUAR4HV"
	inviteCodeDecimal = 32
	inviteCodePad     = "A"
	inviteCodeLen     = 8
)

// EncodeInviteCode 生成邀请码
func EncodeInviteCode(uid uint64) string {
	id := uid
	res := ""
	for id != 0 {
		mod := id % inviteCodeDecimal
		id = id / inviteCodeDecimal
		res += string(inviteCodeBase[mod])
	}
	if len(res) < inviteCodeLen {
		res += inviteCodePad
		for i := 0; i < inviteCodeLen-len(res)-1; i++ {
			res += string(inviteCodeBase[(int(uid)+i)%inviteCodeDecimal])
		}
	}
	return res
}

// GetRandomCode 生成指定长度的随机数字字符串
func GetRandomCode(length int) string {
	var sb strings.Builder
	r := rand.New(rand.NewSource(time.Now().UnixNano()))
	for i := 0; i < length; i++ {
		fmt.Fprintf(&sb, "%d", r.Intn(10))
	}
	return sb.String()
}

// GetRandomString 生成指定长度的随机字符串
func GetRandomString(length int) string {
	const chars = "0123456789abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
	result := make([]byte, length)
	r := rand.New(rand.NewSource(time.Now().UnixNano()))
	for i := 0; i < length; i++ {
		result[i] = chars[r.Intn(len(chars))]
	}
	return string(result)
}

// UniqueStrings 字符串切片去重
func UniqueStrings(s []string) []string {
	seen := make(map[string]struct{})
	result := make([]string, 0, len(s))
	for _, v := range s {
		if _, ok := seen[v]; !ok {
			seen[v] = struct{}{}
			result = append(result, v)
		}
	}
	return result
}

// HTTPGet 发送GET请求
func HTTPGet(url string) (string, error) {
	client := &http.Client{Timeout: 5 * time.Second}
	resp, err := client.Get(url)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}
	return string(body), nil
}

// HTTPPost 发送POST请求
func HTTPPost(url string, data interface{}, contentType string) (string, error) {
	jsonData, err := json.Marshal(data)
	if err != nil {
		return "", err
	}

	req, err := http.NewRequest("POST", url, bytes.NewBuffer(jsonData))
	if err != nil {
		return "", err
	}
	req.Header.Set("Content-Type", contentType)

	client := &http.Client{Timeout: 5 * time.Second}
	resp, err := client.Do(req)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return "", err
	}
	return string(body), nil
}

// Min 返回两个整数中的较小值
func Min(a, b int) int {
	if a < b {
		return a
	}
	return b
}

// Max 返回两个整数中的较大值
func Max(a, b int) int {
	if a > b {
		return a
	}
	return b
}