//! Persistent job queue and the four job kinds.
//!
//! Backed by Postgres (the `crawler_jobs` table). Workers lease rows
//! with `SELECT ... FOR UPDATE SKIP LOCKED`, heartbeat via
//! `leased_until`, and ack by transitioning to `done` (or backoff /
//! `dead`). Handlers are idempotent so a crash mid-run is recoverable
//! by replay.
//!
//! Scaffold only — the actual queue wrapper and handler dispatch land
//! once we have the first `Source` impl exercising the pipeline.

use serde::{Deserialize, Serialize};
use uuid::Uuid;

use super::source::DiscoverMode;

#[derive(Clone, Debug, Serialize, Deserialize)]
#[serde(tag = "kind", rename_all = "snake_case")]
pub enum JobPayload {
    /// Walk the source index and enqueue `SyncManga` jobs.
    Discover {
        source_id: String,
        mode: DiscoverMode,
    },
    /// Fetch one manga's detail page, upsert metadata, enqueue
    /// `SyncChapterList`.
    SyncManga {
        source_id: String,
        source_manga_key: String,
    },
    /// Diff the chapter list, enqueue `SyncChapterContent` for new
    /// chapters, soft-drop vanished ones.
    SyncChapterList {
        source_id: String,
        manga_id: Uuid,
        source_manga_key: String,
    },
    /// Download a single chapter's page images into storage.
    SyncChapterContent {
        source_id: String,
        chapter_id: Uuid,
        source_chapter_key: String,
    },
}

#[derive(Clone, Copy, Debug, sqlx::Type, Serialize, Deserialize)]
#[sqlx(type_name = "text", rename_all = "snake_case")]
#[serde(rename_all = "snake_case")]
pub enum JobState {
    Pending,
    Running,
    Done,
    Failed,
    Dead,
}