//! Chapter list + get. Reads are public — anyone can browse a manga's
//! table of contents and individual chapter metadata. Uploads land in
//! feat/uploads under POST /api/v1/mangas/{id}/chapters.

use axum::extract::{Path, Query, State};
use axum::routing::get;
use axum::{Json, Router};
use serde::Deserialize;
use uuid::Uuid;

use crate::api::pagination::PagedResponse;
use crate::app::AppState;
use crate::domain::Chapter;
use crate::error::AppResult;
use crate::repo;

pub fn routes() -> Router<AppState> {
    Router::new()
        .route("/mangas/:manga_id/chapters", get(list))
        .route("/mangas/:manga_id/chapters/:number", get(get_one))
}

#[derive(Debug, Deserialize)]
pub struct ListParams {
    #[serde(default = "default_limit")]
    pub limit: i64,
    #[serde(default)]
    pub offset: i64,
}

fn default_limit() -> i64 {
    50
}

async fn list(
    State(state): State<AppState>,
    Path(manga_id): Path<Uuid>,
    Query(params): Query<ListParams>,
) -> AppResult<Json<PagedResponse<Chapter>>> {
    // Surface 404 when the parent manga doesn't exist so an empty result
    // can't be mistaken for "no chapters yet" on a real manga.
    repo::manga::get(&state.db, manga_id).await?;

    let limit = params.limit.clamp(1, 200);
    let offset = params.offset.max(0);
    let items = repo::chapter::list_for_manga(&state.db, manga_id, limit, offset).await?;
    Ok(Json(PagedResponse::new(items, limit, offset)))
}

async fn get_one(
    State(state): State<AppState>,
    Path((manga_id, number)): Path<(Uuid, i32)>,
) -> AppResult<Json<Chapter>> {
    repo::manga::get(&state.db, manga_id).await?;
    let chapter = repo::chapter::find_by_manga_and_number(&state.db, manga_id, number)
        .await?
        .ok_or(crate::error::AppError::NotFound)?;
    Ok(Json(chapter))
}