package server

import (
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"os"
	"path"
	"strconv"
	"time"
	"weatherstation/internal/config"
	"weatherstation/internal/database"
	"weatherstation/pkg/types"

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

// StartGinServer 启动Gin Web服务器
func StartGinServer() error {
	// 设置Gin模式
	gin.SetMode(gin.ReleaseMode)

	// 创建Gin引擎
	r := gin.Default()

	// 加载HTML模板
	r.LoadHTMLGlob("templates/*")

	// 静态文件服务
	r.Static("/static", "./static")
	// 雷达数据静态目录（用于访问 latest 下的图片/二进制）
	r.Static("/radar", "./radar_data")

	// 路由设置
	r.GET("/", indexHandler)

	// API路由组
	api := r.Group("/api")
	{
		api.GET("/system/status", systemStatusHandler)
		api.GET("/stations", getStationsHandler)
		api.GET("/data", getDataHandler)
		api.GET("/forecast", getForecastHandler)
		api.GET("/radar/latest", radarLatestHandler)
		api.GET("/radar/latest/grid", radarLatestGridHandler)
	}

	// 获取配置的Web端口
	port := config.GetConfig().Server.WebPort
	if port == 0 {
		port = 10003 // 默认端口
	}

	// 备注：雷达抓取改为独立 CLI 触发，Web 服务不自动启动后台任务

	// 启动服务器
	fmt.Printf("Gin Web服务器启动，监听端口 %d...\n", port)
	return r.Run(fmt.Sprintf(":%d", port))
}

// indexHandler 处理主页请求
func indexHandler(c *gin.Context) {
	data := types.PageData{
		Title:         "英卓气象站",
		ServerTime:    time.Now().Format("2006-01-02 15:04:05"),
		OnlineDevices: database.GetOnlineDevicesCount(database.GetDB()),
		TiandituKey:   "0c260b8a094a4e0bc507808812cefdac",
	}
	c.HTML(http.StatusOK, "index.html", data)
}

// 备注：雷达站采用前端 Tab（hash）切换，无需单独路由

// systemStatusHandler 处理系统状态API请求
func systemStatusHandler(c *gin.Context) {
	status := types.SystemStatus{
		OnlineDevices: database.GetOnlineDevicesCount(database.GetDB()),
		ServerTime:    time.Now().Format("2006-01-02 15:04:05"),
	}
	c.JSON(http.StatusOK, status)
}

// getStationsHandler 处理获取站点列表API请求
func getStationsHandler(c *gin.Context) {
	stations, err := database.GetStations(database.GetDB())
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "查询站点失败"})
		return
	}

	// 为每个站点计算十进制ID
	for i := range stations {
		if len(stations[i].StationID) > 6 {
			hexID := stations[i].StationID[len(stations[i].StationID)-6:]
			if decimalID, err := strconv.ParseInt(hexID, 16, 64); err == nil {
				stations[i].DecimalID = strconv.FormatInt(decimalID, 10)
			}
		}
	}

	c.JSON(http.StatusOK, stations)
}

// getDataHandler 处理获取历史数据API请求
func getDataHandler(c *gin.Context) {
	// 获取查询参数
	decimalID := c.Query("decimal_id")
	startTime := c.Query("start_time")
	endTime := c.Query("end_time")
	interval := c.Query("interval")

	// 将十进制ID转换为十六进制（补足6位）
	decimalNum, err := strconv.ParseInt(decimalID, 10, 64)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "无效的站点编号"})
		return
	}
	hexID := fmt.Sprintf("%06X", decimalNum)
	stationID := fmt.Sprintf("RS485-%s", hexID)

	// 解析时间（按本地CST解析，避免被当作UTC）
	loc, _ := time.LoadLocation("Asia/Shanghai")
	if loc == nil {
		loc = time.FixedZone("CST", 8*3600)
	}
	start, err := time.ParseInLocation("2006-01-02 15:04:05", startTime, loc)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "无效的开始时间"})
		return
	}

	end, err := time.ParseInLocation("2006-01-02 15:04:05", endTime, loc)
	if err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "无效的结束时间"})
		return
	}

	// 获取数据（改为基于10分钟聚合表的再聚合）
	var points []types.WeatherPoint
	if interval == "raw" {
		points, err = database.GetSeriesRaw(database.GetDB(), stationID, start, end)
	} else {
		points, err = database.GetSeriesFrom10Min(database.GetDB(), stationID, start, end, interval)
	}
	if err != nil {
		log.Printf("查询数据失败: %v", err) // 记录具体错误到服务端日志
		c.JSON(http.StatusInternalServerError, gin.H{
			"error": fmt.Sprintf("查询数据失败: %v", err),
		})
		return
	}

	c.JSON(http.StatusOK, points)
}

// getForecastHandler 处理获取预报数据API请求
func getForecastHandler(c *gin.Context) {
	// 获取查询参数
	stationID := c.Query("station_id")
	startTime := c.Query("from")
	endTime := c.Query("to")
	provider := c.Query("provider")
	versionsStr := c.DefaultQuery("versions", "1")
	versions, _ := strconv.Atoi(versionsStr)
	if versions <= 0 {
		versions = 1
	}

	if stationID == "" {
		c.JSON(http.StatusBadRequest, gin.H{"error": "缺少station_id参数"})
		return
	}

	// 如果没有提供时间范围，则默认查询未来3小时
	loc, _ := time.LoadLocation("Asia/Shanghai")
	if loc == nil {
		loc = time.FixedZone("CST", 8*3600)
	}

	var start, end time.Time
	var err error

	if startTime == "" || endTime == "" {
		// 默认查询未来3小时
		now := time.Now().In(loc)
		start = now.Truncate(time.Hour).Add(1 * time.Hour) // 下一个整点开始
		end = start.Add(3 * time.Hour)                     // 未来3小时
	} else {
		// 解析用户提供的时间
		start, err = time.ParseInLocation("2006-01-02 15:04:05", startTime, loc)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": "无效的开始时间格式"})
			return
		}

		end, err = time.ParseInLocation("2006-01-02 15:04:05", endTime, loc)
		if err != nil {
			c.JSON(http.StatusBadRequest, gin.H{"error": "无效的结束时间格式"})
			return
		}
	}

	// 获取预报数据
	log.Printf("查询预报数据: stationID=%s, provider=%s, versions=%d, start=%s, end=%s", stationID, provider, versions, start.Format("2006-01-02 15:04:05"), end.Format("2006-01-02 15:04:05"))
	points, err := database.GetForecastData(database.GetDB(), stationID, start, end, provider, versions)
	if err != nil {
		log.Printf("查询预报数据失败: %v", err)
		c.JSON(http.StatusInternalServerError, gin.H{
			"error": fmt.Sprintf("查询预报数据失败: %v", err),
		})
		return
	}

	log.Printf("查询到预报数据: %d 条", len(points))
	c.JSON(http.StatusOK, points)
}

// radarLatestHandler 返回最新一次雷达抓取的元数据与图片URL
func radarLatestHandler(c *gin.Context) {
	// 读取 latest/metadata.json
	latestRoot := "./radar_data/latest"
	metaPath := latestRoot + "/metadata.json"
	b, err := os.ReadFile(metaPath)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "未找到最新雷达元数据"})
		return
	}
	var meta map[string]any
	if err := json.Unmarshal(b, &meta); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "解析元数据失败"})
		return
	}
	// 构造图片URL（通过 /radar/latest/* 静态路径访问）
	images := map[string]string{
		"china":   "/radar/latest/nmc_chinaall.png",
		"huanan":  "/radar/latest/nmc_huanan.png",
		"nanning": "/radar/latest/nmc_nanning.png",
	}
	if files, ok := meta["files"].(map[string]any); ok {
		if v, ok2 := files["cma_png"].(string); ok2 && v != "" {
			_, name := path.Split(v)
			images["cma"] = "/radar/latest/" + name
		}
	}
	c.JSON(http.StatusOK, gin.H{
		"meta":   meta,
		"images": images,
	})
}

// radarLatestGridHandler 读取 latest 下的 z-y-x.bin 并返回 256x256 的 dBZ 二维数组（无效为 null）
func radarLatestGridHandler(c *gin.Context) {
	latestRoot := "./radar_data/latest"
	metaPath := latestRoot + "/metadata.json"
	b, err := os.ReadFile(metaPath)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "未找到最新雷达元数据"})
		return
	}
	var meta map[string]any
	if err := json.Unmarshal(b, &meta); err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "解析元数据失败"})
		return
	}
	z := intFromMeta(meta, "z")
	y := intFromMeta(meta, "y")
	x := intFromMeta(meta, "x")
	binName := fmt.Sprintf("%d-%d-%d.bin", z, y, x)
	binPath := path.Join(latestRoot, binName)
	buf, err := os.ReadFile(binPath)
	if err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "未找到最新BIN文件"})
		return
	}
	const w, h = 256, 256
	if len(buf) != w*h*2 {
		c.JSON(http.StatusBadRequest, gin.H{"error": "BIN尺寸异常"})
		return
	}
	grid := make([][]*float64, h)
	for r := 0; r < h; r++ {
		row := make([]*float64, w)
		for c2 := 0; c2 < w; c2++ {
			off := (r*w + c2) * 2
			u := uint16(buf[off])<<8 | uint16(buf[off+1])
			v := int16(u)
			if v == 32767 || v < 0 {
				row[c2] = nil
				continue
			}
			dbz := float64(v) / 10.0
			row[c2] = &dbz
		}
		grid[r] = row
	}
	bounds := map[string]float64{"west": 0, "south": 0, "east": 0, "north": 0}
	if v, ok := meta["bounds"].(map[string]any); ok {
		if f, ok2 := v["west"].(float64); ok2 {
			bounds["west"] = f
		}
		if f, ok2 := v["south"].(float64); ok2 {
			bounds["south"] = f
		}
		if f, ok2 := v["east"].(float64); ok2 {
			bounds["east"] = f
		}
		if f, ok2 := v["north"].(float64); ok2 {
			bounds["north"] = f
		}
	}
	resDeg := 0.0
	if f, ok := meta["res_deg"].(float64); ok {
		resDeg = f
	}
	c.JSON(http.StatusOK, gin.H{
		"z": z, "y": y, "x": x,
		"bounds":  bounds,
		"res_deg": resDeg,
		"grid":    grid,
	})
}

func intFromMeta(m map[string]any, key string) int {
	if v, ok := m[key]; ok {
		switch t := v.(type) {
		case float64:
			return int(t)
		case int:
			return t
		}
	}
	return 0
}