package main

import (
	"database/sql"
	"fmt"
	"net/http"
	"strconv"
	"time"

	"weatherstation/config"

	"github.com/gin-gonic/gin"
	_ "github.com/lib/pq"
)

var ginDB *sql.DB

func initGinDB() error {
	cfg := config.GetConfig()

	connStr := fmt.Sprintf("host=%s port=%d user=%s password=%s dbname=%s sslmode=%s",
		cfg.Database.Host, cfg.Database.Port, cfg.Database.User,
		cfg.Database.Password, cfg.Database.DBName, cfg.Database.SSLMode)

	var err error
	ginDB, err = sql.Open("postgres", connStr)
	if err != nil {
		return fmt.Errorf("无法连接到数据库: %v", err)
	}

	err = ginDB.Ping()
	if err != nil {
		return fmt.Errorf("数据库连接测试失败: %v", err)
	}

	return nil
}

// 获取在线设备数量
func getOnlineDevicesCount() int {
	if ginDB == nil {
		return 0
	}

	query := `
		SELECT COUNT(DISTINCT station_id) 
		FROM rs485_weather_data 
		WHERE timestamp > NOW() - INTERVAL '5 minutes'`

	var count int
	err := ginDB.QueryRow(query).Scan(&count)
	if err != nil {
		return 0
	}
	return count
}

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

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

// 获取WH65LP站点列表API
func getStationsHandler(c *gin.Context) {
	query := `
		SELECT DISTINCT s.station_id, 
			COALESCE(s.password, '') as station_name,
			'WH65LP' as device_type,
			COALESCE(MAX(r.timestamp), '1970-01-01'::timestamp) as last_update,
			COALESCE(s.latitude, 0) as latitude,
			COALESCE(s.longitude, 0) as longitude,
			COALESCE(s.name, '') as name,
			COALESCE(s.location, '') as location
		FROM stations s
		LEFT JOIN rs485_weather_data r ON s.station_id = r.station_id
		WHERE s.station_id LIKE 'RS485-%'
		GROUP BY s.station_id, s.password, s.latitude, s.longitude, s.name, s.location
		ORDER BY s.station_id`

	rows, err := ginDB.Query(query)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "查询站点失败"})
		return
	}
	defer rows.Close()

	var stations []Station
	for rows.Next() {
		var station Station
		var lastUpdate time.Time
		err := rows.Scan(
			&station.StationID,
			&station.StationName,
			&station.DeviceType,
			&lastUpdate,
			&station.Latitude,
			&station.Longitude,
			&station.Name,
			&station.Location,
		)
		if err != nil {
			continue
		}
		station.LastUpdate = lastUpdate.Format("2006-01-02 15:04:05")

		// 从station_id中提取十六进制ID并转换为十进制
		if len(station.StationID) > 6 {
			hexID := station.StationID[len(station.StationID)-6:]
			if decimalID, err := strconv.ParseInt(hexID, 16, 64); err == nil {
				station.DecimalID = strconv.FormatInt(decimalID, 10)
			}
		}

		stations = append(stations, station)
	}

	c.JSON(http.StatusOK, stations)
}

// 获取历史数据API
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)

	// 构建查询SQL（统一风向矢量平均，雨量为累计量的正增量求和）
	var query string
	switch interval {
	case "10min":
		query = `
			WITH base AS (
				SELECT 
					date_trunc('hour', timestamp) + (floor(date_part('minute', timestamp) / 10) * interval '10 minute') as time_group,
					timestamp as ts,
					temperature, humidity, pressure, wind_speed, wind_direction, rainfall, light, uv
				FROM rs485_weather_data
				WHERE station_id = $1 AND timestamp BETWEEN $2 AND $3
			),
			rain_inc AS (
				SELECT time_group, GREATEST(rainfall - LAG(rainfall) OVER (PARTITION BY time_group ORDER BY ts), 0) AS inc
				FROM base
			),
			rain_sum AS (
				SELECT time_group, SUM(inc) AS rainfall
				FROM rain_inc
				GROUP BY time_group
			),
			grouped_data AS (
				SELECT 
					time_group,
					AVG(temperature) as temperature,
					AVG(humidity) as humidity,
					AVG(pressure) as pressure,
					AVG(wind_speed) as wind_speed,
					DEGREES(ATAN2(AVG(SIN(RADIANS(wind_direction))), AVG(COS(RADIANS(wind_direction))))) AS wind_direction_raw,
					AVG(light) as light,
					AVG(uv) as uv
				FROM base
				GROUP BY time_group
			)
			SELECT 
				to_char(g.time_group, 'YYYY-MM-DD HH24:MI:SS') as date_time,
				ROUND(g.temperature::numeric, 2) as temperature,
				ROUND(g.humidity::numeric, 2) as humidity,
				ROUND(g.pressure::numeric, 2) as pressure,
				ROUND(g.wind_speed::numeric, 2) as wind_speed,
				ROUND((CASE WHEN g.wind_direction_raw < 0 THEN g.wind_direction_raw + 360 ELSE g.wind_direction_raw END)::numeric, 2) AS wind_direction,
				ROUND(COALESCE(r.rainfall, 0)::numeric, 3) as rainfall,
				ROUND(g.light::numeric, 2) as light,
				ROUND(g.uv::numeric, 2) as uv
			FROM grouped_data g
			LEFT JOIN rain_sum r ON r.time_group = g.time_group
			ORDER BY g.time_group`
	case "30min":
		query = `
			WITH base AS (
				SELECT 
					date_trunc('hour', timestamp) + (floor(date_part('minute', timestamp) / 30) * interval '30 minute') as time_group,
					timestamp as ts,
					temperature, humidity, pressure, wind_speed, wind_direction, rainfall, light, uv
				FROM rs485_weather_data
				WHERE station_id = $1 AND timestamp BETWEEN $2 AND $3
			),
			rain_inc AS (
				SELECT time_group, GREATEST(rainfall - LAG(rainfall) OVER (PARTITION BY time_group ORDER BY ts), 0) AS inc
				FROM base
			),
			rain_sum AS (
				SELECT time_group, SUM(inc) AS rainfall
				FROM rain_inc
				GROUP BY time_group
			),
			grouped_data AS (
				SELECT 
					time_group,
					AVG(temperature) as temperature,
					AVG(humidity) as humidity,
					AVG(pressure) as pressure,
					AVG(wind_speed) as wind_speed,
					DEGREES(ATAN2(AVG(SIN(RADIANS(wind_direction))), AVG(COS(RADIANS(wind_direction))))) AS wind_direction_raw,
					AVG(light) as light,
					AVG(uv) as uv
				FROM base
				GROUP BY time_group
			)
			SELECT 
				to_char(g.time_group, 'YYYY-MM-DD HH24:MI:SS') as date_time,
				ROUND(g.temperature::numeric, 2) as temperature,
				ROUND(g.humidity::numeric, 2) as humidity,
				ROUND(g.pressure::numeric, 2) as pressure,
				ROUND(g.wind_speed::numeric, 2) as wind_speed,
				ROUND((CASE WHEN g.wind_direction_raw < 0 THEN g.wind_direction_raw + 360 ELSE g.wind_direction_raw END)::numeric, 2) AS wind_direction,
				ROUND(COALESCE(r.rainfall, 0)::numeric, 3) as rainfall,
				ROUND(g.light::numeric, 2) as light,
				ROUND(g.uv::numeric, 2) as uv
			FROM grouped_data g
			LEFT JOIN rain_sum r ON r.time_group = g.time_group
			ORDER BY g.time_group`
	default: // 1hour
		query = `
			WITH base AS (
				SELECT 
					date_trunc('hour', timestamp) as time_group,
					timestamp as ts,
					temperature, humidity, pressure, wind_speed, wind_direction, rainfall, light, uv
				FROM rs485_weather_data
				WHERE station_id = $1 AND timestamp BETWEEN $2 AND $3
			),
			rain_inc AS (
				SELECT time_group, GREATEST(rainfall - LAG(rainfall) OVER (PARTITION BY time_group ORDER BY ts), 0) AS inc
				FROM base
			),
			rain_sum AS (
				SELECT time_group, SUM(inc) AS rainfall
				FROM rain_inc
				GROUP BY time_group
			),
			grouped_data AS (
				SELECT 
					time_group,
					AVG(temperature) as temperature,
					AVG(humidity) as humidity,
					AVG(pressure) as pressure,
					AVG(wind_speed) as wind_speed,
					DEGREES(ATAN2(AVG(SIN(RADIANS(wind_direction))), AVG(COS(RADIANS(wind_direction))))) AS wind_direction_raw,
					AVG(light) as light,
					AVG(uv) as uv
				FROM base
				GROUP BY time_group
			)
			SELECT 
				to_char(g.time_group, 'YYYY-MM-DD HH24:MI:SS') as date_time,
				ROUND(g.temperature::numeric, 2) as temperature,
				ROUND(g.humidity::numeric, 2) as humidity,
				ROUND(g.pressure::numeric, 2) as pressure,
				ROUND(g.wind_speed::numeric, 2) as wind_speed,
				ROUND((CASE WHEN g.wind_direction_raw < 0 THEN g.wind_direction_raw + 360 ELSE g.wind_direction_raw END)::numeric, 2) AS wind_direction,
				ROUND(COALESCE(r.rainfall, 0)::numeric, 3) as rainfall,
				ROUND(g.light::numeric, 2) as light,
				ROUND(g.uv::numeric, 2) as uv
			FROM grouped_data g
			LEFT JOIN rain_sum r ON r.time_group = g.time_group
			ORDER BY g.time_group`
	}

	// 执行查询
	rows, err := ginDB.Query(query, stationID, startTime, endTime)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "查询数据失败"})
		return
	}
	defer rows.Close()

	var weatherPoints []WeatherPoint
	for rows.Next() {
		var point WeatherPoint
		err := rows.Scan(
			&point.DateTime,
			&point.Temperature,
			&point.Humidity,
			&point.Pressure,
			&point.WindSpeed,
			&point.WindDir,
			&point.Rainfall,
			&point.Light,
			&point.UV,
		)
		if err != nil {
			continue
		}
		weatherPoints = append(weatherPoints, point)
	}

	c.JSON(http.StatusOK, weatherPoints)
}

func StartGinServer() {
	err := initGinDB()
	if err != nil {
		fmt.Printf("初始化Gin数据库连接失败: %v\n", err)
		return
	}

	// 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")

	// 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)
	}

	// 启动服务器
	fmt.Println("Gin Web服务器启动，监听端口 10003...")
	r.Run(":10003")
}