feat: 添加收藏功能 API

- models.rs: 添加 is_favorite 字段到 WeatherData 和 WeatherDataBrief
- db.rs: 添加 get_favorites_list 和 set_weather_favorite 函数
- handlers/favorites.rs: 新建收藏 API 处理器
- handlers/mod.rs: 导出 favorites 模块
- main.rs: 注册收藏 API 路由

src/db.rs

@@ -34,10 +34,10 @@ pub async fn insert_weather_data(pool: &PgPool, weather_data: &WeatherData, user
             atmosphericstability, suitabilitydegree, winddirection, averagewinddirection,
             winddirectionstandarddeviation, windspeed, averagewindspeed, windspeedsuitability,
             winddirectionsuitability, overallsuitability, inspectiontype, assignmentnumber,
-            calculatedwindspeed, hasspotcheckwindspeed, version
+            calculatedwindspeed, hasspotcheckwindspeed, version, is_favorite
         ) VALUES (
             $1, $2, $3, $4, $5, $6, $7, $8, $9, $10, $11, $12, $13, $14, $15, $16, $17, $18, $19,
-            $20, $21, $22, $23, $24, $25, $26, $27, $28, $29, $30, $31, $32, $33, $34, $35, $36
+            $20, $21, $22, $23, $24, $25, $26, $27, $28, $29, $30, $31, $32, $33, $34, $35, $36, $37
         ) RETURNING id
     "#;
 
@@ -85,6 +85,7 @@ pub async fn insert_weather_data(pool: &PgPool, weather_data: &WeatherData, user
         .bind(weather_data.calculated_wind_speed) // 这个本来就是 Option，无需修改
         .bind(weather_data.has_spot_check_wind_speed)
         .bind(&weather_data.version)
+        .bind(weather_data.is_favorite)
         .fetch_one(pool)
         .await
     {
@@ -129,7 +130,7 @@ pub async fn get_weather_details(pool: &PgPool, weather_id: i32) -> Result<Weath
             wd.winddirectionstandarddeviation, wd.windspeed, wd.averagewindspeed,
             wd.windspeedsuitability, wd.winddirectionsuitability, wd.overallsuitability,
             wd.inspectiontype, wd.assignmentnumber, wd.calculatedwindspeed, wd.hasspotcheckwindspeed,
-            u.openid, wd.version
+            wd.is_favorite, u.openid, wd.version
         FROM weather_data wd
         JOIN users u ON wd.user_id = u.id
         WHERE wd.id = $1
@@ -175,7 +176,7 @@ pub async fn get_weather_list(
     // 2. 查询当前页数据列表
     let list_query = r#"
         SELECT 
-            wd.id, wd.title, wd.date, wd.hour, wd.min, wd.longitude, wd.latitude
+            wd.id, wd.title, wd.date, wd.hour, wd.min, wd.longitude, wd.latitude, wd.is_favorite
         FROM weather_data wd
         WHERE wd.user_id = $1
         ORDER BY wd.date DESC, wd.hour DESC, wd.min DESC
@@ -404,3 +405,73 @@ pub async fn get_user_quota(
     let used = count_user_weather_data(pool, user_id).await?;
     Ok((used, is_paid_active, user.paid_expires_at))
 }
+
+// ===== 收藏功能 DB 函数 =====
+
+/// 获取收藏列表（分页）
+pub async fn get_favorites_list(
+    pool: &PgPool,
+    user_id: i32,
+    page: i32,
+    limit: i32,
+) -> Result<WeatherListResponse, String> {
+    let offset = (page - 1) * limit;
+
+    let total_query = r#"
+        SELECT COUNT(*) as total
+        FROM weather_data
+        WHERE user_id = $1 AND is_favorite = true
+    "#;
+    let total = sqlx::query_as::<_, (i64,)>(total_query)
+        .bind(user_id)
+        .fetch_one(pool)
+        .await
+        .map_err(|e| format!("查询收藏总数失败: {}", e))?
+        .0;
+
+    let list_query = r#"
+        SELECT
+            id, title, date, hour, min, longitude, latitude, is_favorite
+        FROM weather_data
+        WHERE user_id = $1 AND is_favorite = true
+        ORDER BY date DESC, hour DESC, min DESC
+        LIMIT $2 OFFSET $3
+    "#;
+    let list = sqlx::query_as::<_, WeatherDataBrief>(list_query)
+        .bind(user_id)
+        .bind(limit)
+        .bind(offset)
+        .fetch_all(pool)
+        .await
+        .map_err(|e| format!("查询收藏列表失败: {}", e))?;
+
+    Ok(WeatherListResponse { list, total })
+}
+
+/// 设置天气数据的收藏状态
+pub async fn set_weather_favorite(
+    pool: &PgPool,
+    weather_id: i32,
+    user_id: i32,
+    is_favorite: bool,
+) -> Result<(), String> {
+    let query = r#"
+        UPDATE weather_data
+        SET is_favorite = $1
+        WHERE id = $2 AND user_id = $3
+    "#;
+
+    let result = sqlx::query(query)
+        .bind(is_favorite)
+        .bind(weather_id)
+        .bind(user_id)
+        .execute(pool)
+        .await
+        .map_err(|e| format!("更新收藏状态失败: {}", e))?;
+
+    if result.rows_affected() == 0 {
+        return Err(format!("未找到ID为 {} 的天气数据或无权限修改", weather_id));
+    }
+
+    Ok(())
+}