//! 定时任务数据库服务层

use sqlx::{PgPool, FromRow};
use crate::error::SaasResult;
use super::types::*;

/// 数据库行结构
#[derive(Debug, FromRow)]
#[allow(dead_code)] // @reserved: FromRow deserialization struct; fields accessed via destructuring
struct ScheduledTaskRow {
    id: String,
    account_id: String,
    name: String,
    description: Option<String>,
    schedule: String,
    schedule_type: String,
    target_type: String,
    target_id: String,
    enabled: bool,
    last_run_at: Option<String>,
    next_run_at: Option<String>,
    run_count: i32,
    last_result: Option<String>,
    last_error: Option<String>,
    last_duration_ms: Option<i64>,
    input_payload: Option<serde_json::Value>,
    created_at: String,
}

impl ScheduledTaskRow {
    fn to_response(&self) -> ScheduledTaskResponse {
        ScheduledTaskResponse {
            id: self.id.clone(),
            name: self.name.clone(),
            schedule: self.schedule.clone(),
            schedule_type: self.schedule_type.clone(),
            target: TaskTarget {
                target_type: self.target_type.clone(),
                id: self.target_id.clone(),
            },
            enabled: self.enabled,
            description: self.description.clone(),
            last_run: self.last_run_at.clone(),
            next_run: self.next_run_at.clone(),
            run_count: self.run_count,
            last_result: self.last_result.clone(),
            last_error: self.last_error.clone(),
            last_duration_ms: self.last_duration_ms,
            created_at: self.created_at.clone(),
        }
    }
}

/// 创建定时任务
pub async fn create_task(
    db: &PgPool,
    account_id: &str,
    req: &CreateScheduledTaskRequest,
) -> SaasResult<ScheduledTaskResponse> {
    let id = uuid::Uuid::new_v4().to_string();
    let now = chrono::Utc::now();
    let input_json: Option<String> = req.input.as_ref().map(|v| v.to_string());

    sqlx::query(
        "INSERT INTO scheduled_tasks (id, account_id, name, description, schedule, schedule_type, target_type, target_id, enabled, input_payload, created_at, updated_at)
         VALUES ($1, $2, $3, $4, $5, $6, $7, $8, $9, $10::jsonb, $11, $11)"
    )
    .bind(&id)
    .bind(account_id)
    .bind(&req.name)
    .bind(&req.description)
    .bind(&req.schedule)
    .bind(&req.schedule_type)
    .bind(&req.target.target_type)
    .bind(&req.target.id)
    .bind(req.enabled.unwrap_or(true))
    .bind(&input_json)
    .bind(&now)
    .execute(db)
    .await?;

    Ok(ScheduledTaskResponse {
        id,
        name: req.name.clone(),
        schedule: req.schedule.clone(),
        schedule_type: req.schedule_type.clone(),
        target: req.target.clone(),
        enabled: req.enabled.unwrap_or(true),
        description: req.description.clone(),
        last_run: None,
        next_run: None,
        run_count: 0,
        last_result: None,
        last_error: None,
        last_duration_ms: None,
        created_at: now.to_rfc3339(),
    })
}

/// 列出用户的定时任务
pub async fn list_tasks(
    db: &PgPool,
    account_id: &str,
) -> SaasResult<Vec<ScheduledTaskResponse>> {
    let rows: Vec<ScheduledTaskRow> = sqlx::query_as(
        "SELECT id, account_id, name, description, schedule, schedule_type,
                target_type, target_id, enabled, last_run_at, next_run_at,
                run_count, last_result, last_error, last_duration_ms, input_payload, created_at::TEXT
         FROM scheduled_tasks WHERE account_id = $1 ORDER BY created_at DESC"
    )
    .bind(account_id)
    .fetch_all(db)
    .await?;

    Ok(rows.iter().map(|r| r.to_response()).collect())
}

/// 获取单个定时任务
pub async fn get_task(
    db: &PgPool,
    account_id: &str,
    task_id: &str,
) -> SaasResult<ScheduledTaskResponse> {
    let row: Option<ScheduledTaskRow> = sqlx::query_as(
        "SELECT id, account_id, name, description, schedule, schedule_type,
                target_type, target_id, enabled, last_run_at, next_run_at,
                run_count, last_result, last_error, last_duration_ms, input_payload, created_at::TEXT
         FROM scheduled_tasks WHERE id = $1 AND account_id = $2"
    )
    .bind(task_id)
    .bind(account_id)
    .fetch_optional(db)
    .await?;

    Ok(row
        .ok_or_else(|| crate::error::SaasError::NotFound("定时任务不存在".into()))?
        .to_response())
}

/// 更新定时任务
pub async fn update_task(
    db: &PgPool,
    account_id: &str,
    task_id: &str,
    req: &UpdateScheduledTaskRequest,
) -> SaasResult<ScheduledTaskResponse> {
    let existing = get_task(db, account_id, task_id).await?;

    let name = req.name.as_deref().unwrap_or(&existing.name);
    let schedule = req.schedule.as_deref().unwrap_or(&existing.schedule);
    let schedule_type = req.schedule_type.as_deref().unwrap_or(&existing.schedule_type);
    let enabled = req.enabled.unwrap_or(existing.enabled);
    let description = req.description.as_deref().or(existing.description.as_deref());
    let now = chrono::Utc::now();

    let (target_type, target_id) = if let Some(ref target) = req.target {
        (target.target_type.as_str(), target.id.as_str())
    } else {
        (existing.target.target_type.as_str(), existing.target.id.as_str())
    };

    sqlx::query(
        "UPDATE scheduled_tasks SET name = $1, schedule = $2, schedule_type = $3,
                target_type = $4, target_id = $5, enabled = $6, description = $7,
                updated_at = $8
         WHERE id = $9 AND account_id = $10"
    )
    .bind(name)
    .bind(schedule)
    .bind(schedule_type)
    .bind(target_type)
    .bind(target_id)
    .bind(enabled)
    .bind(description)
    .bind(&now)
    .bind(task_id)
    .bind(account_id)
    .execute(db)
    .await?;

    get_task(db, account_id, task_id).await
}

/// 删除定时任务
pub async fn delete_task(
    db: &PgPool,
    account_id: &str,
    task_id: &str,
) -> SaasResult<()> {
    let result = sqlx::query(
        "DELETE FROM scheduled_tasks WHERE id = $1 AND account_id = $2"
    )
    .bind(task_id)
    .bind(account_id)
    .execute(db)
    .await?;

    if result.rows_affected() == 0 {
        return Err(crate::error::SaasError::NotFound("定时任务不存在".into()));
    }
    Ok(())
}