//go:build windows

package main

import (
	"bytes"
	"encoding/json"
	"fmt"
	"image"
	"net/http"
	"strings"
	"time"
	"unicode/utf8"

	"github.com/lxn/walk"
	. "github.com/lxn/walk/declarative"
	"github.com/lxn/win"
	qrcode "github.com/skip2/go-qrcode"
)

type guiAPIResponse struct {
	Code    int             `json:"code"`
	Message string          `json:"message"`
	Data    json.RawMessage `json:"data"`
}

type guiCardData struct {
	Name       string `json:"Name"`
	IDNum      string `json:"IDNum"`
	CardNum    string `json:"CardNum"`
	CardIDCode string `json:"CardIDCode"`
}

func runGUIProcess() int {
	cfg, err := loadConfig()
	if err != nil {
		walk.MsgBox(nil, "读卡程序", err.Error(), walk.MsgBoxIconError)
		return 1
	}
	if err = runGUI(cfg); err != nil {
		walk.MsgBox(nil, "读卡程序", err.Error(), walk.MsgBoxIconError)
		return 1
	}
	return 0
}

func runGUI(cfg Config) error {
	var window *walk.MainWindow
	var qrView *walk.ImageView
	var message *walk.Label
	var readButton *walk.PushButton
	var currentBitmap *walk.Bitmap

	setMessage := func(text string, isError bool) {
		message.SetText(text)
		if isError {
			message.SetTextColor(walk.RGB(196, 43, 28))
		} else {
			message.SetTextColor(walk.RGB(90, 98, 108))
		}
	}

	readCard := func() {
		readButton.SetEnabled(false)
		readButton.SetText("正在读卡…")
		_ = qrView.SetImage(nil)
		if currentBitmap != nil {
			currentBitmap.Dispose()
			currentBitmap = nil
		}
		setMessage("请保持卡片位置不动", false)
		go func() {
			card, failure := requestCard(cfg)
			var qrImage image.Image
			if failure == nil {
				content := buildQRContent(card)
				if strings.Trim(content, "|") == "" {
					failure = fmt.Errorf("读卡成功，但未获取到有效卡片信息")
				} else {
					code, qrErr := qrcode.New(content, qrcode.Medium)
					if qrErr != nil {
						failure = fmt.Errorf("生成二维码失败：%w", qrErr)
					} else {
						qrImage = code.Image(300)
					}
				}
			}

			window.Synchronize(func() {
				defer func() {
					readButton.SetEnabled(true)
					readButton.SetText("读卡")
				}()
				if failure != nil {
					setMessage(failure.Error(), true)
					return
				}
				bitmap, bitmapErr := walk.NewBitmapFromImage(qrImage)
				if bitmapErr != nil {
					setMessage("显示二维码失败："+bitmapErr.Error(), true)
					return
				}
				if err := qrView.SetImage(bitmap); err != nil {
					bitmap.Dispose()
					setMessage("显示二维码失败："+err.Error(), true)
					return
				}
				if currentBitmap != nil {
					currentBitmap.Dispose()
				}
				currentBitmap = bitmap
				setMessage("读卡成功，请扫描二维码", false)
			})
		}()
	}

	windowDef := MainWindow{
		AssignTo:   &window,
		Title:      "社保卡读卡",
		Size:       Size{520, 590},
		MinSize:    Size{520, 590},
		MaxSize:    Size{520, 590},
		Background: SolidColorBrush{Color: walk.RGB(247, 249, 252)},
		Layout:     VBox{MarginsZero: true, SpacingZero: true},
		Children: []Widget{
			Composite{
				Layout: VBox{Margins: Margins{24, 22, 24, 12}, Spacing: 12},
				Children: []Widget{
					Label{Text: "社保卡读卡", Font: Font{Family: "Microsoft YaHei UI", PointSize: 16, Bold: true}, TextColor: walk.RGB(30, 38, 50)},
					ImageView{AssignTo: &qrView, MinSize: Size{320, 320}, Mode: ImageViewModeCenter, Background: SolidColorBrush{Color: walk.RGB(255, 255, 255)}},
					Label{AssignTo: &message, Text: "请放置社保卡，然后点击读卡", Font: Font{Family: "Microsoft YaHei UI", PointSize: 10}, Alignment: AlignHCenterVCenter, TextAlignment: AlignCenter, MinSize: Size{0, 52}, TextColor: walk.RGB(90, 98, 108)},
				},
			},
			Composite{
				Background: SolidColorBrush{Color: walk.RGB(255, 255, 255)},
				Layout:     HBox{Margins: Margins{24, 18, 24, 18}},
				Children: []Widget{
					HSpacer{},
					PushButton{AssignTo: &readButton, Text: "读卡", MinSize: Size{150, 44}, Font: Font{Family: "Microsoft YaHei UI", PointSize: 11, Bold: true}, OnClicked: readCard},
					HSpacer{},
				},
			},
		},
	}
	if err := windowDef.Create(); err != nil {
		return err
	}
	// Keep only the requested minimize and close buttons in the title bar.
	style := win.GetWindowLong(window.Handle(), win.GWL_STYLE)
	win.SetWindowLong(window.Handle(), win.GWL_STYLE, style&^win.WS_MAXIMIZEBOX)
	defer func() {
		if currentBitmap != nil {
			currentBitmap.Dispose()
		}
		window.Dispose()
	}()
	window.Run()
	return nil
}

func requestCard(cfg Config) (guiCardData, error) {
	body, _ := json.Marshal(map[string]string{"reader_type": cfg.GUIReaderType})
	client := &http.Client{Timeout: 2 * time.Minute}
	host := cfg.Host
	if host == "0.0.0.0" || host == "::" {
		host = "127.0.0.1"
	}
	url := fmt.Sprintf("http://%s:%d/api/card/read-nopin", host, cfg.Port)
	var lastErr error
	for attempt := 0; attempt < 8; attempt++ {
		response, err := client.Post(url, "application/json", bytes.NewReader(body))
		if err != nil {
			lastErr = err
			time.Sleep(250 * time.Millisecond)
			continue
		}
		defer response.Body.Close()
		var payload guiAPIResponse
		if err = json.NewDecoder(response.Body).Decode(&payload); err != nil {
			return guiCardData{}, fmt.Errorf("读卡服务返回格式错误：%w", err)
		}
		if response.StatusCode != http.StatusOK || payload.Code != 0 {
			if strings.TrimSpace(payload.Message) == "" {
				payload.Message = fmt.Sprintf("读卡失败（状态码 %d）", response.StatusCode)
			}
			return guiCardData{}, fmt.Errorf("%s", payload.Message)
		}
		var card guiCardData
		if err = json.Unmarshal(payload.Data, &card); err != nil {
			return guiCardData{}, fmt.Errorf("无法解析卡片信息：%w", err)
		}
		return card, nil
	}
	return guiCardData{}, fmt.Errorf("无法连接读卡服务：%v", lastErr)
}

func buildQRContent(card guiCardData) string {
	return encodeURIComponent(card.Name) + "|" + card.IDNum + "|" + card.CardNum + "|" + card.CardIDCode
}

// encodeURIComponent matches JavaScript's encodeURIComponent for UTF-8 text.
func encodeURIComponent(value string) string {
	const hex = "0123456789ABCDEF"
	var result strings.Builder
	result.Grow(len(value))
	for len(value) > 0 {
		r, size := utf8.DecodeRuneInString(value)
		if r == utf8.RuneError && size == 1 {
			r = '\uFFFD'
		}
		encoded := make([]byte, utf8.RuneLen(r))
		utf8.EncodeRune(encoded, r)
		for _, b := range encoded {
			if (b >= 'a' && b <= 'z') || (b >= 'A' && b <= 'Z') || (b >= '0' && b <= '9') || strings.ContainsRune("-_.!~*'()", rune(b)) {
				result.WriteByte(b)
			} else {
				result.WriteByte('%')
				result.WriteByte(hex[b>>4])
				result.WriteByte(hex[b&15])
			}
		}
		value = value[size:]
	}
	return result.String()
}