package main

import (
	"database/sql"
	"fmt"
	"time"
	
	_ "github.com/go-sql-driver/mysql"
)

var db *sql.DB
const SCALING_FACTOR = 1000 // 浮点数到整数的转换因子

// 初始化数据库连接
func InitDB() error {
	// 调整这些参数以匹配你的MySQL配置
	username := "root"
	password := "root"  // 请替换为你的实际密码
	host := "localhost"
	port := "3306"
	dbName := "probe_db"
	
	// 连接字符串
	dsn := fmt.Sprintf("%s:%s@tcp(%s:%s)/%s?parseTime=true", username, password, host, port, dbName)
	
	var err error
	db, err = sql.Open("mysql", dsn)
	if err != nil {
		return err
	}
	
	// 测试连接
	err = db.Ping()
	if err != nil {
		return err
	}
	
	// 设置连接池参数
	db.SetMaxOpenConns(10)
	db.SetMaxIdleConns(5)
	db.SetConnMaxLifetime(time.Minute * 5)
	
	return nil
}

// 关闭数据库连接
func CloseDB() {
	if db != nil {
		db.Close()
	}
}

// 保存传感器数据 - 将浮点值转换为整数存储
func SaveSensorData(sensorID int, x, y, z float64) error {
	// 转换为整数，乘以1000并四舍五入
	xInt := int(x * SCALING_FACTOR)
	yInt := int(y * SCALING_FACTOR)
	zInt := int(z * SCALING_FACTOR)
	
	query := `INSERT INTO sensor_data (sensor_id, x_value, y_value, z_value) VALUES (?, ?, ?, ?)`
	_, err := db.Exec(query, sensorID, xInt, yInt, zInt)
	return err
}

// 获取传感器数据 - 从整数转换回浮点数
// 获取传感器数据 - 添加时间范围
func GetSensorData(sensorID int, limit int, startDate time.Time, endDate time.Time) ([]SensorData, error) {
    // 基本查询
    query := `SELECT id, sensor_id, x_value, y_value, z_value, 
             timestamp as timestamp 
             FROM sensor_data 
             WHERE sensor_id = ?`
    
    // 添加查询条件
    var args []interface{}
    args = append(args, sensorID)
    
    // 添加日期范围
    if !startDate.IsZero() {
        query += " AND timestamp >= ?"
        args = append(args, startDate)
    }
    
    if !endDate.IsZero() {
        query += " AND timestamp <= ?"
        args = append(args, endDate)
    }
    
    // 添加排序和限制
    query += " ORDER BY timestamp DESC LIMIT ?"
    args = append(args, limit)
    
    // 执行查询
    rows, err := db.Query(query, args...)
    if err != nil {
        return nil, err
    }
    defer rows.Close()
    
    var result []SensorData
    
    for rows.Next() {
        var data SensorData
        var xInt, yInt, zInt int
        
        err := rows.Scan(&data.ID, &data.SensorID, &xInt, &yInt, &zInt, &data.Timestamp)
        if err != nil {
            return nil, err
        }
        
        // 从整数转换回浮点数
        data.X = float64(xInt) / SCALING_FACTOR
        data.Y = float64(yInt) / SCALING_FACTOR
        data.Z = float64(zInt) / SCALING_FACTOR
        
        result = append(result, data)
    }
    
    return result, nil
}

// 获取所有传感器数据
func GetAllSensorData(limit int, startDate time.Time, endDate time.Time) ([]SensorData, error) {
    // 基本查询
    query := `SELECT id, sensor_id, x_value, y_value, z_value, 
             timestamp as timestamp 
             FROM sensor_data 
             WHERE 1=1`
    
    // 添加查询条件
    var args []interface{}
    
    // 添加日期范围
    if !startDate.IsZero() {
        query += " AND timestamp >= ?"
        args = append(args, startDate)
    }
    
    if !endDate.IsZero() {
        query += " AND timestamp <= ?"
        args = append(args, endDate)
    }
    
    // 添加排序和限制
    query += " ORDER BY timestamp DESC LIMIT ?"
    args = append(args, limit)
    
    // 执行查询
    rows, err := db.Query(query, args...)
    if err != nil {
        return nil, err
    }
    defer rows.Close()
    
    var result []SensorData
    
    for rows.Next() {
        var data SensorData
        var xInt, yInt, zInt int
        
        err := rows.Scan(&data.ID, &data.SensorID, &xInt, &yInt, &zInt, &data.Timestamp)
        if err != nil {
            return nil, err
        }
        
        // 从整数转换回浮点数
        data.X = float64(xInt) / SCALING_FACTOR
        data.Y = float64(yInt) / SCALING_FACTOR
        data.Z = float64(zInt) / SCALING_FACTOR
        
        result = append(result, data)
    }
    
    return result, nil
}
// 获取所有传感器ID
func GetAllSensorIDs() ([]int, error) {
	query := `SELECT DISTINCT sensor_id FROM sensor_data ORDER BY sensor_id`
	
	rows, err := db.Query(query)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	
	var ids []int
	for rows.Next() {
		var id int
		if err := rows.Scan(&id); err != nil {
			return nil, err
		}
		ids = append(ids, id)
	}
	
	return ids, nil
}

// SensorData 结构用于存储传感器数据
type SensorData struct {
	ID        int       `json:"id"`
	SensorID  int       `json:"sensor_id"`
	X         float64   `json:"x"`
	Y         float64   `json:"y"`
	Z         float64   `json:"z"`
	Timestamp time.Time `json:"timestamp"`
}