package main

import (
	"embed"
	"encoding/json"
	"fmt"
	"io"
	"net/http"
	"os"
	"path/filepath"
	"strings"
	"time"

	"github.com/getlantern/systray"
)

//go:embed icon.ico
var icon []byte

var _ = embed.FS{} // 保证 Go 1.26+ embed 引用检查

// ---------- 配置常量 ----------
const (
	apiTimeout       = 15 * time.Second  // HTTP 请求超时
	refreshPeriod    = 10 * time.Minute   // 自动刷新间隔
	lowBalanceYuan   = 1.0                // 低余额告警阈值（元）
	balanceDefaultURL = "https://api.deepseek.com/user/balance"
)

var (
	apiKey     string
	balanceURL = balanceDefaultURL
)

// ---------- API 响应 ----------
type balanceResp struct {
	IsAvailable  bool          `json:"is_available"`
	BalanceInfos []balanceItem `json:"balance_infos"`
}

type balanceItem struct {
	Currency        string `json:"currency"`
	TotalBalance    string `json:"total_balance"`
	GrantedBalance  string `json:"granted_balance"`
	ToppedUpBalance string `json:"topped_up_balance"`
}

// ---------- 入口 ----------
func main() {
	loadDotEnv()
	apiKey = envOr("DEEPSEEK_API_KEY", "")
	if v := envOr("DEEPSEEK_BALANCE_URL", ""); v != "" {
		balanceURL = v
	}
	systray.Run(onReady, func() {})
}

func onReady() {
	systray.SetIcon(icon)
	systray.SetTitle("DeepSeek")
	if apiKey == "" {
		systray.SetTooltip("DeepSeek - 未配置 API Key\n请在 .env 文件中设置 DEEPSEEK_API_KEY")
	} else {
		systray.SetTooltip("DeepSeek 余额查询 - 正在获取...")
	}

	// 菜单
	mBalance := systray.AddMenuItem("余额: 查询中...", "")
	mBalance.Disable()
	mRefresh := systray.AddMenuItem("刷新余额", "手动刷新")
	mAuto := systray.AddMenuItem("自动刷新: 开启", "切换自动刷新")
	mAlert := systray.AddMenuItem("低余额告警: 关闭", "切换低余额告警")
	systray.AddSeparator()
	mDotEnv := systray.AddMenuItem("打开 .env 配置文件", "编辑 API Key")
	mAbout := systray.AddMenuItem("关于", "状态信息")
	mQuit := systray.AddMenuItem("退出", "关闭程序")

	// 运行时状态（仅在事件循环 goroutine 中访问，无数据竞争）
	autoRefresh := true
	alertOn := false
	var ticker *time.Ticker
	var tickStop chan struct{}

	startTick := func() {
		ticker = time.NewTicker(refreshPeriod)
		tickStop = make(chan struct{})
		go func() {
			for {
				select {
				case <-ticker.C:
					if apiKey != "" {
						balance, _ := refreshAndUpdate(mBalance)
						if alertOn && balance < lowBalanceYuan && balance > 0 {
	showMessageBox("DeepSeek 余额不足",
								fmt.Sprintf("当前余额 ¥%.2f，低于阈值 ¥%.0f，请及时充值。", balance, lowBalanceYuan))
						}
					}
				case <-tickStop:
					ticker.Stop()
					return
				}
			}
		}()
	}

	stopTick := func() {
		if tickStop != nil {
			close(tickStop)
			tickStop = nil
		}
	}

	startTick()

	// 首次查询
	go func() {
		if apiKey == "" {
			mBalance.SetTitle("余额: 未配置 Key")
			mBalance.SetTooltip("点击「打开 .env 配置文件」设置 API Key")
		} else {
			refreshAndUpdate(mBalance)
		}
	}()

	// 事件循环
	for {
		select {
		case <-mRefresh.ClickedCh:
			if apiKey == "" {
	showMessageBox("DeepSeek Tray",
					"未配置 API Key。\n请点击「打开 .env 配置文件」设置 DEEPSEEK_API_KEY。")
			} else {
				refreshAndUpdate(mBalance)
			}

		case <-mAuto.ClickedCh:
			if autoRefresh {
				stopTick()
				mAuto.SetTitle("自动刷新: 关闭")
			} else {
				startTick()
				mAuto.SetTitle("自动刷新: 开启")
			}
			autoRefresh = !autoRefresh

		case <-mAlert.ClickedCh:
			alertOn = !alertOn
			if alertOn {
				mAlert.SetTitle("低余额告警: 开启")
				mAlert.SetTooltip(fmt.Sprintf("余额低于 ¥%.0f 时提醒", lowBalanceYuan))
				if apiKey != "" {
					balance, _ := refreshAndUpdate(mBalance)
					if balance < lowBalanceYuan && balance > 0 {
						showMessageBox("DeepSeek 余额不足",
							fmt.Sprintf("当前余额 ¥%.2f，低于阈值 ¥%.0f，请及时充值。", balance, lowBalanceYuan))
					}
				}
			} else {
				mAlert.SetTitle("低余额告警: 关闭")
				mAlert.SetTooltip("切换低余额告警")
			}

		case <-mDotEnv.ClickedCh:
			openDotEnv()

		case <-mAbout.ClickedCh:
			ar := "否"
			if autoRefresh {
				ar = "是"
			}
			ao := "否"
			if alertOn {
				ao = "是"
			}
	showMessageBox("DeepSeek Balance Tray",
				fmt.Sprintf("DeepSeek 余额查询系统托盘\n\n自动刷新: %s\n刷新间隔: %d 分钟\n低余额告警: %s\n\n配置文件: .env",
					ar, int(refreshPeriod.Minutes()), ao))

		case <-mQuit.ClickedCh:
			stopTick()
			systray.Quit()
			return
		}
	}
}

// ---------- 核心：余额获取与 UI 更新 ----------

// refreshAndUpdate 请求 API 并更新托盘状态，返回 CNY 余额数值。
func refreshAndUpdate(m *systray.MenuItem) (cnyBalance float64, err error) {
	text, currency, cny := fetchBalance()

	tooltip := fmt.Sprintf("DeepSeek 余额: %s %s\n更新时间: %s",
		text, currency, time.Now().Format("15:04:05"))
	systray.SetTooltip(tooltip)
	m.SetTitle("余额: " + text + " " + currency)
	m.SetTooltip(tooltip)

	if cny > 0 {
		systray.SetTitle(text)
	} else {
		systray.SetTitle("DeepSeek")
	}
	return cny, nil
}

// fetchBalance 返回 (余额文本, 货币, CNY 数值)。
func fetchBalance() (string, string, float64) {
	client := &http.Client{Timeout: apiTimeout}
	req, err := http.NewRequest("GET", balanceURL, nil)
	if err != nil {
		return "创建请求失败", "", 0
	}
	req.Header.Set("Authorization", "Bearer "+apiKey)
	req.Header.Set("Accept", "application/json")

	resp, err := client.Do(req)
	if err != nil {
		return "网络错误: " + err.Error(), "", 0
	}
	defer resp.Body.Close()

	if resp.StatusCode == http.StatusUnauthorized {
		return "API Key 无效", "", 0
	}
	if resp.StatusCode != http.StatusOK {
		body, _ := io.ReadAll(io.LimitReader(resp.Body, 512))
		return fmt.Sprintf("HTTP %d: %s", resp.StatusCode, string(body)), "", 0
	}

	var br balanceResp
	if err := json.NewDecoder(resp.Body).Decode(&br); err != nil {
		return "解析响应失败", "", 0
	}

	if !br.IsAvailable || len(br.BalanceInfos) == 0 {
		return "余额不可用", "", 0
	}

	// 取第一个币种为主显示，叠加所有 CNY 为数值
	info := br.BalanceInfos[0]
	first := fmt.Sprintf("%s %s", info.TotalBalance, info.Currency)

	var cnyTotal float64
	for _, item := range br.BalanceInfos {
		var v float64
		fmt.Sscanf(item.TotalBalance, "%f", &v)
		if item.Currency == "CNY" {
			cnyTotal += v
		}
	}

	return first, info.Currency, cnyTotal
}

// ---------- .env 支持 ----------

func loadDotEnv() {
	dir := exeDir()
	if dir == "" {
		return
	}
	data, err := os.ReadFile(filepath.Join(dir, ".env"))
	if err != nil {
		return
	}
	for _, line := range strings.Split(string(data), "\n") {
		line = strings.TrimSpace(line)
		if line == "" || line[0] == '#' {
			continue
		}
		idx := strings.IndexByte(line, '=')
		if idx < 0 {
			continue
		}
		key := strings.TrimSpace(line[:idx])
		val := strings.Trim(strings.TrimSpace(line[idx+1:]), `"`)
		// .env 不覆盖已有环境变量
		if os.Getenv(key) == "" && key != "" {
			os.Setenv(key, val)
		}
	}
}

func openDotEnv() {
	dir := exeDir()
	if dir == "" {
	showMessageBox("错误", "无法获取程序路径")
		return
	}
	path := filepath.Join(dir, ".env")

	if _, err := os.Stat(path); os.IsNotExist(err) {
		tmpl := "# DeepSeek API Key（必填）\nDEEPSEEK_API_KEY=sk-your-key-here\n\n# 余额查询接口（可选）\n# DEEPSEEK_BALANCE_URL=https://api.deepseek.com/user/balance\n"
		if err := os.WriteFile(path, []byte(tmpl), 0644); err != nil {
	showMessageBox("错误", "无法创建 .env 文件: "+err.Error())
			return
		}
	}

	runNotepad(path)
}

// exeDir 返回可执行文件所在目录路径。
func exeDir() string {
	p, err := os.Executable()
	if err != nil {
		return ""
	}
	return filepath.Dir(p)
}

// ---------- 工具 ----------

func envOr(key, def string) string {
	if v, ok := os.LookupEnv(key); ok && v != "" {
		return v
	}
	return def
}