Implement compression quota refunds and admin manual subscription

src/services/billing.rs

@@ -0,0 +1,135 @@
+use crate::error::{AppError, ErrorCode};
+use crate::state::AppState;
+
+use chrono::{DateTime, Datelike, TimeZone, Utc};
+use sqlx::FromRow;
+use uuid::Uuid;
+
+#[derive(Debug, Clone)]
+pub struct Plan {
+    pub id: Uuid,
+    pub code: String,
+    pub included_units_per_period: i32,
+    pub max_file_size_mb: i32,
+    pub max_files_per_batch: i32,
+    pub retention_days: i32,
+    pub feature_api_enabled: bool,
+}
+
+#[derive(Debug, Clone)]
+pub struct BillingContext {
+    pub user_id: Uuid,
+    pub subscription_id: Option<Uuid>,
+    pub plan: Plan,
+    pub period_start: DateTime<Utc>,
+    pub period_end: DateTime<Utc>,
+}
+
+#[derive(Debug, FromRow)]
+struct SubscriptionRow {
+    id: Uuid,
+    status: String,
+    current_period_start: DateTime<Utc>,
+    current_period_end: DateTime<Utc>,
+    plan_id: Uuid,
+}
+
+#[derive(Debug, FromRow)]
+struct PlanRow {
+    id: Uuid,
+    code: String,
+    included_units_per_period: i32,
+    max_file_size_mb: i32,
+    max_files_per_batch: i32,
+    retention_days: i32,
+    features: serde_json::Value,
+}
+
+pub async fn get_user_billing(state: &AppState, user_id: Uuid) -> Result<BillingContext, AppError> {
+    let subscription = sqlx::query_as::<_, SubscriptionRow>(
+        r#"
+        SELECT id, status::text AS status, current_period_start, current_period_end, plan_id
+        FROM subscriptions
+        WHERE user_id = $1
+          AND status IN ('active', 'trialing', 'past_due')
+        ORDER BY current_period_end DESC
+        LIMIT 1
+        "#,
+    )
+    .bind(user_id)
+    .fetch_optional(&state.db)
+    .await
+    .map_err(|err| AppError::new(ErrorCode::Internal, "查询订阅失败").with_source(err))?;
+
+    let (subscription_id, period_start, period_end, plan_id) = if let Some(sub) = subscription {
+        if sub.status == "past_due" {
+            return Err(AppError::new(
+                ErrorCode::Forbidden,
+                "订阅欠费，请先完成支付",
+            ));
+        }
+        (Some(sub.id), sub.current_period_start, sub.current_period_end, sub.plan_id)
+    } else {
+        let plan_id: Uuid = sqlx::query_scalar("SELECT id FROM plans WHERE code = 'free' LIMIT 1")
+            .fetch_one(&state.db)
+            .await
+            .map_err(|err| AppError::new(ErrorCode::Internal, "未找到 Free 套餐").with_source(err))?;
+        let (start, end) = current_month_period_utc8(Utc::now());
+        (None, start, end, plan_id)
+    };
+
+    let plan_row = sqlx::query_as::<_, PlanRow>(
+        r#"
+        SELECT id, code, included_units_per_period, max_file_size_mb, max_files_per_batch, retention_days, features
+        FROM plans
+        WHERE id = $1
+        "#,
+    )
+    .bind(plan_id)
+    .fetch_one(&state.db)
+    .await
+        .map_err(|err| AppError::new(ErrorCode::Internal, "查询套餐失败").with_source(err))?;
+
+    let feature_api_enabled = plan_row
+        .features
+        .get("api")
+        .and_then(|v| v.as_bool())
+        .unwrap_or(false);
+
+    Ok(BillingContext {
+        user_id,
+        subscription_id,
+        plan: Plan {
+            id: plan_row.id,
+            code: plan_row.code,
+            included_units_per_period: plan_row.included_units_per_period,
+            max_file_size_mb: plan_row.max_file_size_mb,
+            max_files_per_batch: plan_row.max_files_per_batch,
+            retention_days: plan_row.retention_days,
+            feature_api_enabled,
+        },
+        period_start,
+        period_end,
+    })
+}
+
+pub fn current_month_period_utc8(now_utc: DateTime<Utc>) -> (DateTime<Utc>, DateTime<Utc>) {
+    let tz = chrono::FixedOffset::east_opt(8 * 3600).unwrap();
+    let now = now_utc.with_timezone(&tz);
+    let year = now.year();
+    let month = now.month();
+
+    let start = tz.with_ymd_and_hms(year, month, 1, 0, 0, 0).single().unwrap();
+
+    let (next_year, next_month) = if month == 12 {
+        (year + 1, 1)
+    } else {
+        (year, month + 1)
+    };
+    let end = tz
+        .with_ymd_and_hms(next_year, next_month, 1, 0, 0, 0)
+        .single()
+        .unwrap();
+
+    (start.with_timezone(&Utc), end.with_timezone(&Utc))
+}