package web

import (
	"fmt"
	"net/http"
	"strconv"

	"xiaji-go/models"

	"github.com/gin-gonic/gin"
	"gorm.io/gorm"
)

type WebServer struct {
	db       *gorm.DB
	port     int
	username string
	password string
}

func NewWebServer(db *gorm.DB, port int, username, password string) *WebServer {
	return &WebServer{db: db, port: port, username: username, password: password}
}

func (s *WebServer) Start() {
	gin.SetMode(gin.ReleaseMode)
	r := gin.Default()
	r.LoadHTMLGlob("templates/*")

	// 页面
	r.GET("/", s.handleIndex)
	r.GET("/api/records", s.handleRecords)
	r.POST("/delete/:id", s.handleDelete)
	r.GET("/export", s.handleExport)

	// 健康检查
	r.GET("/health", func(c *gin.Context) {
		c.JSON(http.StatusOK, gin.H{"status": "ok"})
	})

	logAddr := fmt.Sprintf(":%d", s.port)
	fmt.Printf("🌐 Web后台运行在 http://127.0.0.1%s\n", logAddr)
	if err := r.Run(logAddr); err != nil {
		fmt.Printf("❌ Web服务启动失败: %v\n", err)
	}
}

func (s *WebServer) handleIndex(c *gin.Context) {
	c.HTML(http.StatusOK, "index.html", nil)
}

func (s *WebServer) handleRecords(c *gin.Context) {
	var items []models.Transaction
	s.db.Where("is_deleted = ?", false).Order("id desc").Limit(50).Find(&items)

	type txResponse struct {
		ID       uint    `json:"id"`
		UserID   int64   `json:"user_id"`
		Amount   float64 `json:"amount"`
		Category string  `json:"category"`
		Note     string  `json:"note"`
		Date     string  `json:"date"`
	}

	resp := make([]txResponse, len(items))
	for i, item := range items {
		resp[i] = txResponse{
			ID:       item.ID,
			UserID:   item.UserID,
			Amount:   item.AmountYuan(),
			Category: item.Category,
			Note:     item.Note,
			Date:     item.Date,
		}
	}

	c.JSON(http.StatusOK, resp)
}

func (s *WebServer) handleDelete(c *gin.Context) {
	idStr := c.Param("id")
	id, err := strconv.ParseUint(idStr, 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "无效的ID"})
		return
	}

	result := s.db.Model(&models.Transaction{}).Where("id = ? AND is_deleted = ?", id, false).Update("is_deleted", true)
	if result.Error != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "删除失败"})
		return
	}
	if result.RowsAffected == 0 {
		c.JSON(http.StatusNotFound, gin.H{"error": "记录不存在或已删除"})
		return
	}

	c.JSON(http.StatusOK, gin.H{"status": "success"})
}

func (s *WebServer) handleExport(c *gin.Context) {
	var items []models.Transaction
	s.db.Where("is_deleted = ?", false).Order("date asc, id asc").Find(&items)

	c.Header("Content-Type", "text/csv; charset=utf-8")
	c.Header("Content-Disposition", "attachment; filename=transactions.csv")

	// BOM for Excel
	c.Writer.Write([]byte{0xEF, 0xBB, 0xBF})
	c.Writer.WriteString("ID,日期,分类,金额(元),备注\n")

	for _, item := range items {
		line := fmt.Sprintf("%d,%s,%s,%.2f,\"%s\"\n", item.ID, item.Date, item.Category, item.AmountYuan(), item.Note)
		c.Writer.WriteString(line)
	}
}