package printer

import (
	"crypto/rand"
	"encoding/hex"
	"fmt"
	"strings"

	"github.com/gin-gonic/gin"
	"wails-app/internal/dao"
	"wails-app/internal/global"
	commonModel "wails-app/internal/model/common"
	"wails-app/internal/model/common/response"
	printService "wails-app/internal/modules/printer/service"
	"wails-app/internal/service"
)

var printSvc = printService.NewPrintService()

type ticketMachinePassage interface {
	HandlePassage(commonModel.PassageRequest) (*commonModel.PassageResult, error)
}

type ticketMachinePrinter interface {
	PrintTicket(printerID uint, lotName, channelCode, plateNo string, ticketID uint, ticketNo string) error
}

type buttonReq struct {
	PrinterID   uint   `json:"printer_id"`
	ChannelCode string `json:"channel_code"`
	DeviceCode  string `json:"device_code"`
	PlateNo     string `json:"plate_number"`
}

type rawPrintDebugReq struct {
	DeviceName string `json:"device_name"`
}

type ticketMachineResult struct {
	SessionID        uint   `json:"session_id"`
	TicketID         uint   `json:"ticket_id"`
	TicketNo         string `json:"ticket_no"`
	SlipNo           uint   `json:"slip_no"`
	EntryTime        int64  `json:"entry_time"`
	PlateNumber      string `json:"plate_number"`
	AnonymousVehicle bool   `json:"anonymous_vehicle"`
	ParkingLotID     uint   `json:"parking_lot_id"`
	ParkingLotName   string `json:"parking_lot_name"`
	ChannelCode      string `json:"channel_code"`
	ChannelName      string `json:"channel_name"`
	DeviceCode       string `json:"device_code"`
	DeviceName       string `json:"device_name"`
	BusinessStatus   string `json:"business_status"`
	GateStatus       string `json:"gate_status"`
	PrintStatus      string `json:"print_status"`
}

func generateTicketMachineIdentity(prefix string) (string, error) {
	data := make([]byte, 8)
	if _, err := rand.Read(data); err != nil {
		return "", fmt.Errorf("生成票机车辆标识失败: %w", err)
	}
	return prefix + strings.ToUpper(hex.EncodeToString(data)), nil
}

func resolveTicketMachineLocation(req buttonReq) (*dao.Channel, *dao.UHFReader, *dao.ParkingLot, error) {
	if global.GVA_DB == nil {
		return nil, nil, nil, fmt.Errorf("数据库未初始化")
	}
	channelCode := strings.TrimSpace(req.ChannelCode)
	if channelCode == "" {
		return nil, nil, nil, fmt.Errorf("通道编码不能为空")
	}

	var channel dao.Channel
	if err := global.GVA_DB.Where("channel_code = ?", channelCode).First(&channel).Error; err != nil {
		return nil, nil, nil, fmt.Errorf("票机通道不存在: %s", channelCode)
	}
	if channel.Direction != "in" && channel.Direction != "inout" {
		return nil, nil, nil, fmt.Errorf("票机只能绑定入口或双向通道: %s", channelCode)
	}
	if channel.ParkingLotID == 0 {
		return nil, nil, nil, fmt.Errorf("票机通道未配置停车场: %s", channelCode)
	}

	var devices []dao.UHFReader
	deviceCode := strings.TrimSpace(req.DeviceCode)
	query := global.GVA_DB.Where("channel_id = ? AND is_active = ?", channel.ID, true)
	if deviceCode != "" {
		query = query.Where("device_code = ?", deviceCode)
	}
	if err := query.Order("id").Find(&devices).Error; err != nil {
		return nil, nil, nil, err
	}
	if len(devices) == 0 {
		if deviceCode == "" {
			return nil, nil, nil, fmt.Errorf("票机通道没有绑定启用的闸机设备: %s", channelCode)
		}
		return nil, nil, nil, fmt.Errorf("设备未启用或不属于票机通道: %s", deviceCode)
	}
	if len(devices) > 1 {
		return nil, nil, nil, fmt.Errorf("票机通道绑定了多个启用设备，必须指定 device_code")
	}

	var lot dao.ParkingLot
	if err := global.GVA_DB.First(&lot, channel.ParkingLotID).Error; err != nil {
		return nil, nil, nil, fmt.Errorf("票机通道所属停车场不存在")
	}
	return &channel, &devices[0], &lot, nil
}

func processTicketMachineButton(req buttonReq, passage ticketMachinePassage, printer ticketMachinePrinter) (*ticketMachineResult, error) {
	if req.PrinterID == 0 {
		return nil, fmt.Errorf("打印机ID不能为空")
	}
	channel, device, lot, err := resolveTicketMachineLocation(req)
	if err != nil {
		return nil, err
	}

	displayPlate := strings.TrimSpace(req.PlateNo)
	plateNumber := displayPlate
	anonymous := plateNumber == ""
	if anonymous {
		plateNumber, err = generateTicketMachineIdentity("TKT")
		if err != nil {
			return nil, err
		}
	}

	passageResult, passageErr := passage.HandlePassage(commonModel.PassageRequest{
		PlateNumber:   plateNumber,
		DeviceCode:    device.DeviceCode,
		Direction:     "in",
		TriggerSource: "ticket_machine",
	})
	if passageResult == nil {
		if passageErr == nil {
			passageErr = fmt.Errorf("统一通行入口未返回处理结果")
		}
		return nil, passageErr
	}

	result := &ticketMachineResult{
		SessionID:        passageResult.SessionID,
		TicketID:         passageResult.TicketID,
		TicketNo:         passageResult.TicketNo,
		SlipNo:           passageResult.TicketID,
		EntryTime:        passageResult.EntryTime,
		PlateNumber:      passageResult.PlateNumber,
		AnonymousVehicle: anonymous,
		ParkingLotID:     lot.ID,
		ParkingLotName:   lot.LotName,
		ChannelCode:      channel.ChannelCode,
		ChannelName:      channel.ChannelName,
		DeviceCode:       device.DeviceCode,
		DeviceName:       device.DeviceName,
		BusinessStatus:   "completed",
		GateStatus:       passageResult.GateStatus,
		PrintStatus:      "pending",
	}
	if !passageResult.BusinessCompleted {
		result.BusinessStatus = "failed"
		if passageErr == nil {
			passageErr = fmt.Errorf("统一通行入口未完成入场业务")
		}
		return result, passageErr
	}
	if result.SessionID == 0 || result.TicketID == 0 || result.TicketNo == "" {
		result.PrintStatus = "skipped"
		return result, fmt.Errorf("统一通行入口未返回新建会话和数字票")
	}

	if err := printer.PrintTicket(req.PrinterID, lot.LotName, channel.ChannelCode, displayPlate, result.TicketID, result.TicketNo); err != nil {
		result.PrintStatus = "failed"
		if passageErr != nil {
			return result, fmt.Errorf("%v；打印失败: %w", passageErr, err)
		}
		return result, fmt.Errorf("打印失败: %w", err)
	}
	result.PrintStatus = "printed"
	if passageErr != nil {
		return result, passageErr
	}
	return result, nil
}

func handleTicketMachineButton(c *gin.Context, req buttonReq) {
	result, err := processTicketMachineButton(
		req,
		&service.ServiceGroupApp.ParkingServiceGroup.PassageService,
		printSvc,
	)
	if err != nil {
		if result != nil {
			response.FailWithDetailed(result, err.Error(), c)
			return
		}
		response.FailWithMessage(err.Error(), c)
		return
	}
	response.OkWithData(result, c)
}

// TicketMachineButton 处理真实票机按钮事件，业务统一进入 PassageService。
func TicketMachineButton(c *gin.Context) {
	var req buttonReq
	if err := c.ShouldBindJSON(&req); err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	handleTicketMachineButton(c, req)
}

func TicketMachineButtonTest(c *gin.Context) {
	var req buttonReq
	if err := c.ShouldBindJSON(&req); err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	plateNumber, err := generateTicketMachineIdentity("TEST")
	if err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	req.PlateNo = plateNumber
	handleTicketMachineButton(c, req)
}

func ticketMachineRawPrintDebug(c *gin.Context) {
	var req rawPrintDebugReq
	if err := c.ShouldBindJSON(&req); err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	req.DeviceName = strings.TrimSpace(req.DeviceName)
	if req.DeviceName == "" {
		response.FailWithMessage("打印设备名称不能为空", c)
		return
	}
	if err := printService.InitCSN(printService.FindCsnDllPath()); err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	printService.Csn_EnumUSB()
	printService.Csn_EnumPRN()
	h, err := printService.Csn_OpenUSB(req.DeviceName)
	if err != nil {
		h, err = printService.Csn_OpenPRN(req.DeviceName)
	}
	if err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	defer printService.Csn_Close(h)
	printService.Csn_SetPort(h)
	testData := []byte{0x1B, 0x40, 'T', 'E', 'S', 'T', ' ', 'P', 'R', 'I', 'N', 'T', '\n', '\n', '\n', '\n', 0x1B, 0x69}
	n := printService.Csn_WriteData(testData)
	if n != len(testData) {
		response.FailWithDetailed(gin.H{"bytes_written": n, "bytes_expected": len(testData)}, "打印数据未完整写入", c)
		return
	}
	response.OkWithData(gin.H{
		"device_name": req.DeviceName, "bytes_written": n,
	}, c)
}

func ticketMachineUSBList(c *gin.Context) {
	if err := printService.InitCSN(printService.FindCsnDllPath()); err != nil {
		response.FailWithMessage(err.Error(), c)
		return
	}
	usb := printService.Csn_EnumUSBNames()
	prn := printService.Csn_EnumPRNNames()
	response.OkWithData(gin.H{"usb": usb, "prn": prn}, c)
}

func SetupPrinterRouter(router *gin.RouterGroup) {
	router.POST("/ticket-machine/button", TicketMachineButton)
}

// SetupPrinterDebugRoutes 仅在显式开发配置开启时注册，调用方必须使用私有鉴权路由组。
func SetupPrinterDebugRoutes(router *gin.RouterGroup, enabled bool) {
	if !enabled {
		return
	}
	router.POST("/ticket-machine/test", TicketMachineButtonTest)
	router.POST("/ticket-machine/debug", ticketMachineRawPrintDebug)
	router.GET("/ticket-machine/usb-list", ticketMachineUSBList)
}