package main

import (
	"encoding/json"
	"fmt"
	"html/template"
	"log"
	"net/http"
	"os"
	"path/filepath"
	"strconv"
	"time"
)

// 启动HTTP服务器
func StartHTTPServer(address string) error {
	http.HandleFunc("/", handleIndex)

	http.HandleFunc("/api/data", handleGetData)
	http.HandleFunc("/api/latest", handleGetLatest)
	http.HandleFunc("/api/sensors", handleGetSensors)
	http.HandleFunc("/api/clients", handleGetClients)
	http.HandleFunc("/api/trigger-query", handleTriggerQuery)
	fmt.Printf("HTTP服务器已启动，正在监听 %s\n", address)
	return http.ListenAndServe(address, nil)
}

// 处理主页
func handleIndex(w http.ResponseWriter, r *http.Request) {
	log.Printf("接收到主页请求: %s", r.URL.Path)

	templatePath := "templates/index.html"
	absPath, _ := filepath.Abs(templatePath)

	_, err := os.Stat(templatePath)
	if os.IsNotExist(err) {
		log.Printf("错误: 模板文件不存在: %s", absPath)
		http.Error(w, "模板文件不存在", http.StatusInternalServerError)
		return
	}

	tmpl, err := template.ParseFiles(templatePath)
	if err != nil {
		log.Printf("错误: 无法解析模板: %v", err)
		http.Error(w, "无法加载模板："+err.Error(), http.StatusInternalServerError)
		return
	}

	log.Printf("模板加载成功，开始渲染")
	err = tmpl.Execute(w, nil)
	if err != nil {
		log.Printf("错误: 渲染模板出错: %v", err)
		http.Error(w, "渲染模板出错："+err.Error(), http.StatusInternalServerError)
	}
	log.Printf("模板渲染完成")
}

// 处理获取传感器数据的API
func handleGetData(w http.ResponseWriter, r *http.Request) {
	log.Printf("接收到获取数据请求: %s", r.URL.String())

	w.Header().Set("Content-Type", "application/json")

	sensorIDStr := r.URL.Query().Get("sensor_id")
	limitStr := r.URL.Query().Get("limit")
	startDateStr := r.URL.Query().Get("start_date")
	endDateStr := r.URL.Query().Get("end_date")

	limit := 500     // 默认限制为500条数据
	noLimit := false // 是否不限制数据条数

	var sensorID int
	var err error
	if sensorIDStr != "" && sensorIDStr != "all" {
		sensorID, err = strconv.Atoi(sensorIDStr)
		if err != nil {
			log.Printf("错误: 无效的传感器ID: %s", sensorIDStr)
			http.Error(w, "无效的传感器ID", http.StatusBadRequest)
			return
		}
	}

	if limitStr != "" {
		if limitStr == "all" {
			noLimit = true
			limit = 0 // 设置为0表示不使用LIMIT子句
		} else {
			limit, err = strconv.Atoi(limitStr)
			if err != nil || limit <= 0 {
				log.Printf("错误: 无效的记录数限制: %s", limitStr)
				http.Error(w, "无效的记录数限制", http.StatusBadRequest)
				return
			}
		}
	}

	var startDate, endDate time.Time
	if startDateStr != "" {
		startDate, err = time.Parse("2006-01-02T15:04", startDateStr)
		if err != nil {
			log.Printf("错误: 无效的开始日期: %s, %v", startDateStr, err)
			http.Error(w, "无效的开始日期", http.StatusBadRequest)
			return
		}
	}

	if endDateStr != "" {
		endDate, err = time.Parse("2006-01-02T15:04", endDateStr)
		if err != nil {
			log.Printf("错误: 无效的结束日期: %s, %v", endDateStr, err)
			http.Error(w, "无效的结束日期", http.StatusBadRequest)
			return
		}
	}

	// 特殊处理获取最新数据的请求
	if limit == 1 && sensorIDStr == "" {
		log.Printf("检测到获取最新数据请求 (limit=1)")
	}

	var data []SensorData
	if sensorIDStr == "all" || sensorIDStr == "" {
		data, err = GetAllSensorData(limit, startDate, endDate)
		log.Printf("查询所有传感器数据，limit=%d, 结果数量=%d", limit, len(data))
	} else {
		data, err = GetSensorData(sensorID, limit, startDate, endDate)
		log.Printf("查询传感器%d数据，limit=%d, 结果数量=%d", sensorID, limit, len(data))
	}

	if err != nil {
		log.Printf("错误: 获取数据失败: %v", err)
		http.Error(w, "获取数据失败："+err.Error(), http.StatusInternalServerError)
		return
	}

	// 输出最新数据的详细信息（当limit=1时）
	if limit == 1 && len(data) > 0 {
		latest := data[0]
		log.Printf("返回最新数据: ID=%d, SensorID=%d, X=%.3f, Y=%.3f, Z=%.3f, Temperature=%.1f, Timestamp=%s",
			latest.ID, latest.SensorID, latest.X, latest.Y, latest.Z, latest.Temperature, latest.Timestamp.Format("2006-01-02 15:04:05"))
	}

	if noLimit {
		log.Printf("成功获取到所有数据记录（%d条）", len(data))
	} else {
		log.Printf("成功获取到 %d 条数据记录（限制：%d条）", len(data), limit)
	}

	if err := json.NewEncoder(w).Encode(data); err != nil {
		log.Printf("错误: 编码JSON失败: %v", err)
		http.Error(w, "编码JSON失败："+err.Error(), http.StatusInternalServerError)
	}
}

// 处理获取所有传感器ID的API
func handleGetSensors(w http.ResponseWriter, r *http.Request) {
	log.Printf("接收到获取传感器列表请求")

	w.Header().Set("Content-Type", "application/json")

	sensorIDs, err := GetAllSensorIDs()
	if err != nil {
		log.Printf("错误: 获取传感器ID失败: %v", err)
		http.Error(w, "获取传感器ID失败："+err.Error(), http.StatusInternalServerError)
		return
	}

	log.Printf("成功获取到 %d 个传感器ID", len(sensorIDs))

	if err := json.NewEncoder(w).Encode(sensorIDs); err != nil {
		log.Printf("错误: 编码JSON失败: %v", err)
		http.Error(w, "编码JSON失败："+err.Error(), http.StatusInternalServerError)
	}
}

func handleGetClients(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")

	clients := getAllClients()

	if err := json.NewEncoder(w).Encode(clients); err != nil {
		log.Printf("错误: 编码客户端信息JSON失败: %v", err)
		http.Error(w, "编码JSON失败："+err.Error(), http.StatusInternalServerError)
	}
}

// 处理手动触发查询指令的API
func handleTriggerQuery(w http.ResponseWriter, r *http.Request) {
	w.Header().Set("Content-Type", "application/json")

	if r.Method != "POST" {
		http.Error(w, "只支持POST请求", http.StatusMethodNotAllowed)
		return
	}

	// 触发向所有在线客户端发送查询指令
	sent := triggerManualQuery()

	response := map[string]interface{}{
		"success":    true,
		"message":    fmt.Sprintf("已向%d个客户端发送查询指令", sent),
		"sent_count": sent,
	}

	if err := json.NewEncoder(w).Encode(response); err != nil {
		log.Printf("错误: 编码响应JSON失败: %v", err)
		http.Error(w, "编码JSON失败："+err.Error(), http.StatusInternalServerError)
	}
}

// 处理获取最新传感器数据的API
func handleGetLatest(w http.ResponseWriter, r *http.Request) {
	log.Printf("接收到获取最新数据请求")

	w.Header().Set("Content-Type", "application/json")

	// 获取最新的一条数据
	data, err := GetAllSensorData(1, time.Time{}, time.Time{})
	if err != nil {
		log.Printf("错误: 获取最新数据失败: %v", err)
		http.Error(w, "获取最新数据失败："+err.Error(), http.StatusInternalServerError)
		return
	}

	log.Printf("查询最新数据结果数量: %d", len(data))

	if len(data) == 0 {
		log.Printf("数据库中没有任何数据")
		// 返回空数组而不是错误
		if err := json.NewEncoder(w).Encode([]SensorData{}); err != nil {
			log.Printf("错误: 编码空数据JSON失败: %v", err)
			http.Error(w, "编码JSON失败："+err.Error(), http.StatusInternalServerError)
		}
		return
	}

	// 输出最新数据的详细信息
	latest := data[0]
	log.Printf("返回最新数据: ID=%d, SensorID=%d, X=%.3f, Y=%.3f, Z=%.3f, Temperature=%.1f, Timestamp=%s",
		latest.ID, latest.SensorID, latest.X, latest.Y, latest.Z, latest.Temperature, latest.Timestamp.Format("2006-01-02 15:04:05"))

	if err := json.NewEncoder(w).Encode(data); err != nil {
		log.Printf("错误: 编码最新数据JSON失败: %v", err)
		http.Error(w, "编码JSON失败："+err.Error(), http.StatusInternalServerError)
	}
}