//! Integration tests for the admin storage-usage endpoints
//! (`GET /api/v1/admin/storage`, `POST /api/v1/admin/storage/backfill`).
//!
//! Data is seeded directly via SQL so each test controls the exact byte
//! sizes; the backfill tests additionally drop real blobs into the
//! harness storage tempdir (`_storage_dir`) so `Storage::size` can stat
//! them.

mod common;

use std::fs;
use std::path::Path;

use axum::http::StatusCode;
use axum::Router;
use sqlx::PgPool;
use tower::ServiceExt;
use uuid::Uuid;

use mangalord::repo;

async fn seed_admin(pool: &PgPool, app: &Router) -> String {
    let (username, cookie) = common::register_user(app).await;
    let u = repo::user::find_by_username(pool, &username)
        .await
        .unwrap()
        .unwrap();
    repo::user::set_is_admin_unchecked(pool, u.id, true)
        .await
        .unwrap();
    cookie
}

/// Insert a manga, optionally with a cover size. Returns its id.
async fn insert_manga(pool: &PgPool, title: &str, cover_size: Option<i64>) -> Uuid {
    let id = Uuid::new_v4();
    let cover_path = cover_size.map(|_| format!("mangas/{id}/cover.jpg"));
    sqlx::query(
        "INSERT INTO mangas (id, title, cover_image_path, cover_size_bytes) \
         VALUES ($1, $2, $3, $4)",
    )
    .bind(id)
    .bind(title)
    .bind(cover_path)
    .bind(cover_size)
    .execute(pool)
    .await
    .unwrap();
    id
}

/// Insert a chapter with `page_count` pages each of `size` bytes. Returns
/// the chapter id.
async fn insert_chapter_with_pages(
    pool: &PgPool,
    manga_id: Uuid,
    number: i32,
    page_sizes: &[i64],
) -> Uuid {
    let chapter_id = Uuid::new_v4();
    sqlx::query("INSERT INTO chapters (id, manga_id, number, page_count) VALUES ($1, $2, $3, $4)")
        .bind(chapter_id)
        .bind(manga_id)
        .bind(number)
        .bind(page_sizes.len() as i32)
        .execute(pool)
        .await
        .unwrap();
    for (i, size) in page_sizes.iter().enumerate() {
        let pn = (i + 1) as i32;
        sqlx::query(
            "INSERT INTO pages (chapter_id, page_number, storage_key, content_type, size_bytes) \
             VALUES ($1, $2, $3, 'image/jpeg', $4)",
        )
        .bind(chapter_id)
        .bind(pn)
        .bind(format!("mangas/{manga_id}/chapters/{chapter_id}/pages/{pn:04}.jpg"))
        .bind(size)
        .execute(pool)
        .await
        .unwrap();
    }
    chapter_id
}

#[sqlx::test(migrations = "./migrations")]
async fn requires_admin(pool: PgPool) {
    let h = common::harness(pool);
    let (_u, cookie) = common::register_user(&h.app).await;
    let resp = h
        .app
        .oneshot(common::get_with_cookie("/api/v1/admin/storage", &cookie))
        .await
        .unwrap();
    assert_eq!(resp.status(), StatusCode::FORBIDDEN);
}

#[sqlx::test(migrations = "./migrations")]
async fn unauthenticated_request_is_rejected(pool: PgPool) {
    let h = common::harness(pool);
    let resp = h
        .app
        .oneshot(common::get("/api/v1/admin/storage"))
        .await
        .unwrap();
    assert_eq!(resp.status(), StatusCode::UNAUTHORIZED);
}

#[sqlx::test(migrations = "./migrations")]
async fn empty_library_zeros_and_null_averages(pool: PgPool) {
    let h = common::harness(pool.clone());
    let cookie = seed_admin(&pool, &h.app).await;

    let resp = h
        .app
        .oneshot(common::get_with_cookie("/api/v1/admin/storage", &cookie))
        .await
        .unwrap();
    assert_eq!(resp.status(), StatusCode::OK);
    let body = common::body_json(resp).await;

    assert_eq!(body["total_bytes"].as_i64().unwrap(), 0);
    assert_eq!(body["covers_bytes"].as_i64().unwrap(), 0);
    assert_eq!(body["chapters_bytes"].as_i64().unwrap(), 0);
    assert!(body["avg_image_bytes"].is_null());
    assert!(body["avg_cover_bytes"].is_null());
    assert!(body["avg_chapter_page_bytes"].is_null());
    assert_eq!(body["top_mangas"].as_array().unwrap().len(), 0);
    assert_eq!(body["top_chapters"].as_array().unwrap().len(), 0);
    assert_eq!(body["unmeasured_pages"].as_i64().unwrap(), 0);
    assert_eq!(body["unmeasured_covers"].as_i64().unwrap(), 0);
    // LocalStorage exposes a path so the disk total + ratio are present.
    assert!(body["disk_total_bytes"].as_u64().unwrap() > 0);
    // ratio is 0/disk = 0.0, not null.
    assert_eq!(body["ratio_of_disk"].as_f64().unwrap(), 0.0);
}

#[sqlx::test(migrations = "./migrations")]
async fn totals_split_covers_vs_chapters_and_averages(pool: PgPool) {
    let h = common::harness(pool.clone());
    let cookie = seed_admin(&pool, &h.app).await;

    let m = insert_manga(&pool, "M", Some(100)).await;
    insert_chapter_with_pages(&pool, m, 1, &[200, 400]).await; // 600 chapter bytes

    let resp = h
        .app
        .oneshot(common::get_with_cookie("/api/v1/admin/storage", &cookie))
        .await
        .unwrap();
    let body = common::body_json(resp).await;

    assert_eq!(body["covers_bytes"].as_i64().unwrap(), 100);
    assert_eq!(body["chapters_bytes"].as_i64().unwrap(), 600);
    assert_eq!(body["total_bytes"].as_i64().unwrap(), 700);
    // avg cover = 100; avg chapter page = (200+400)/2 = 300; avg all =
    // (100+200+400)/3 ≈ 233.33.
    assert_eq!(body["avg_cover_bytes"].as_f64().unwrap(), 100.0);
    assert_eq!(body["avg_chapter_page_bytes"].as_f64().unwrap(), 300.0);
    assert!((body["avg_image_bytes"].as_f64().unwrap() - 700.0 / 3.0).abs() < 0.001);
}

#[sqlx::test(migrations = "./migrations")]
async fn top5_mangas_and_chapters_ordered_by_bytes(pool: PgPool) {
    let h = common::harness(pool.clone());
    let cookie = seed_admin(&pool, &h.app).await;

    // Big manga (cover 50 + 1000 page bytes), small manga (cover 10 only).
    let big = insert_manga(&pool, "Big", Some(50)).await;
    insert_chapter_with_pages(&pool, big, 1, &[1000]).await; // heaviest chapter
    let small = insert_manga(&pool, "Small", Some(10)).await;
    insert_chapter_with_pages(&pool, small, 1, &[5]).await;

    let resp = h
        .app
        .oneshot(common::get_with_cookie("/api/v1/admin/storage", &cookie))
        .await
        .unwrap();
    let body = common::body_json(resp).await;

    let mangas = body["top_mangas"].as_array().unwrap();
    assert_eq!(mangas[0]["title"], "Big");
    assert_eq!(mangas[0]["total_bytes"].as_i64().unwrap(), 1050);
    assert_eq!(mangas[1]["title"], "Small");
    assert_eq!(mangas[1]["total_bytes"].as_i64().unwrap(), 15);

    let chapters = body["top_chapters"].as_array().unwrap();
    assert_eq!(chapters[0]["total_bytes"].as_i64().unwrap(), 1000);
    assert_eq!(chapters[0]["manga_id"], big.to_string());
}

fn write_blob(root: &Path, key: &str, bytes: &[u8]) {
    let path = root.join(key);
    fs::create_dir_all(path.parent().unwrap()).unwrap();
    fs::write(path, bytes).unwrap();
}

#[sqlx::test(migrations = "./migrations")]
async fn backfill_fills_unmeasured_pages_and_covers_idempotently(pool: PgPool) {
    let h = common::harness(pool.clone());
    let cookie = seed_admin(&pool, &h.app).await;
    let root = h._storage_dir.path().to_path_buf();

    // A manga with a cover blob but NULL recorded size, and a chapter
    // page with size_bytes = 0 — both are pre-0027 sentinel rows.
    let id = Uuid::new_v4();
    let cover_key = format!("mangas/{id}/cover.jpg");
    sqlx::query("INSERT INTO mangas (id, title, cover_image_path) VALUES ($1, 'M', $2)")
        .bind(id)
        .bind(&cover_key)
        .execute(&pool)
        .await
        .unwrap();
    write_blob(&root, &cover_key, &[0u8; 123]);

    let chapter_id = Uuid::new_v4();
    sqlx::query("INSERT INTO chapters (id, manga_id, number, page_count) VALUES ($1, $2, 1, 1)")
        .bind(chapter_id)
        .bind(id)
        .execute(&pool)
        .await
        .unwrap();
    let page_key = format!("mangas/{id}/chapters/{chapter_id}/pages/0001.jpg");
    // size_bytes omitted → NULL = unmeasured, the backfill target.
    sqlx::query(
        "INSERT INTO pages (chapter_id, page_number, storage_key, content_type) \
         VALUES ($1, 1, $2, 'image/jpeg')",
    )
    .bind(chapter_id)
    .bind(&page_key)
    .execute(&pool)
    .await
    .unwrap();
    write_blob(&root, &page_key, &[0u8; 456]);

    // First backfill fills both.
    let resp = h
        .app
        .clone()
        .oneshot(common::post_json_with_cookie(
            "/api/v1/admin/storage/backfill",
            serde_json::json!({}),
            &cookie,
        ))
        .await
        .unwrap();
    assert_eq!(resp.status(), StatusCode::OK);
    let body = common::body_json(resp).await;
    assert_eq!(body["pages"].as_i64().unwrap(), 1);
    assert_eq!(body["covers"].as_i64().unwrap(), 1);
    assert_eq!(body["missing"].as_i64().unwrap(), 0);
    assert_eq!(body["errored"].as_i64().unwrap(), 0);

    // Sizes are now persisted.
    let page_size: i64 = sqlx::query_scalar("SELECT size_bytes FROM pages WHERE chapter_id = $1")
        .bind(chapter_id)
        .fetch_one(&pool)
        .await
        .unwrap();
    assert_eq!(page_size, 456);
    let cover_size: i64 =
        sqlx::query_scalar("SELECT cover_size_bytes FROM mangas WHERE id = $1")
            .bind(id)
            .fetch_one(&pool)
            .await
            .unwrap();
    assert_eq!(cover_size, 123);

    // Idempotent: a second run finds no sentinel rows.
    let resp2 = h
        .app
        .oneshot(common::post_json_with_cookie(
            "/api/v1/admin/storage/backfill",
            serde_json::json!({}),
            &cookie,
        ))
        .await
        .unwrap();
    let body2 = common::body_json(resp2).await;
    assert_eq!(body2["pages"].as_i64().unwrap(), 0);
    assert_eq!(body2["covers"].as_i64().unwrap(), 0);
    assert_eq!(body2["more_remaining"].as_bool().unwrap(), false);
}

#[sqlx::test(migrations = "./migrations")]
async fn backfill_leaves_a_measured_zero_alone(pool: PgPool) {
    // A page with a *measured* size of 0 (NULL vs 0 distinction) must not
    // be re-stat'd by the backfill — only NULL rows are unmeasured. Guards
    // against a regression that treats 0 as "needs backfill".
    let h = common::harness(pool.clone());
    let cookie = seed_admin(&pool, &h.app).await;
    let m = insert_manga(&pool, "M", None).await;
    let chapter_id = Uuid::new_v4();
    sqlx::query("INSERT INTO chapters (id, manga_id, number, page_count) VALUES ($1, $2, 1, 1)")
        .bind(chapter_id)
        .bind(m)
        .execute(&pool)
        .await
        .unwrap();
    sqlx::query(
        "INSERT INTO pages (chapter_id, page_number, storage_key, content_type, size_bytes) \
         VALUES ($1, 1, 'k/0001.jpg', 'image/jpeg', 0)",
    )
    .bind(chapter_id)
    .execute(&pool)
    .await
    .unwrap();

    // The page's blob does NOT exist on disk; if the backfill wrongly
    // treated size 0 as unmeasured it would try to stat it and report
    // missing. A correct backfill ignores it entirely.
    let resp = h
        .app
        .oneshot(common::post_json_with_cookie(
            "/api/v1/admin/storage/backfill",
            serde_json::json!({}),
            &cookie,
        ))
        .await
        .unwrap();
    let body = common::body_json(resp).await;
    assert_eq!(body["pages"].as_i64().unwrap(), 0);
    assert_eq!(body["missing"].as_i64().unwrap(), 0);
    assert_eq!(body["errored"].as_i64().unwrap(), 0);
}

#[sqlx::test(migrations = "./migrations")]
async fn backfill_caps_per_run_and_reports_more_remaining(pool: PgPool) {
    // More unmeasured rows than the per-run cap (MAX_PER_RUN = 20_000):
    // one run must stop at the cap and report more_remaining = true so the
    // operator knows to run again. Blobs don't exist on disk (we only
    // exercise the cap/keyset path), so every attempt counts as missing.
    let h = common::harness(pool.clone());
    let cookie = seed_admin(&pool, &h.app).await;
    let m = insert_manga(&pool, "M", None).await;
    let chapter_id = Uuid::new_v4();
    sqlx::query("INSERT INTO chapters (id, manga_id, number, page_count) VALUES ($1, $2, 1, 0)")
        .bind(chapter_id)
        .bind(m)
        .execute(&pool)
        .await
        .unwrap();
    // Seed cap + 1 unmeasured pages in a single statement.
    sqlx::query(
        "INSERT INTO pages (chapter_id, page_number, storage_key, content_type) \
         SELECT $1, g, 'k/' || g || '.jpg', 'image/jpeg' FROM generate_series(1, 20001) g",
    )
    .bind(chapter_id)
    .execute(&pool)
    .await
    .unwrap();

    let resp = h
        .app
        .oneshot(common::post_json_with_cookie(
            "/api/v1/admin/storage/backfill",
            serde_json::json!({}),
            &cookie,
        ))
        .await
        .unwrap();
    assert_eq!(resp.status(), StatusCode::OK);
    let body = common::body_json(resp).await;
    // Capped at 20_000 attempts this run; one row left → run again.
    assert_eq!(body["more_remaining"].as_bool().unwrap(), true);
    assert_eq!(body["missing"].as_i64().unwrap(), 20_000);
    assert_eq!(body["pages"].as_i64().unwrap(), 0);
}

#[sqlx::test(migrations = "./migrations")]
async fn backfill_at_exact_cap_is_not_more_remaining(pool: PgPool) {
    // A backlog of exactly the cap (MAX_PER_RUN = 20_000) drains in one run,
    // so more_remaining must be false — no spurious "run again" prompt. This
    // pins the cap/drain boundary (the keyset peek finds nothing past the
    // cursor) that a plain `budget == 0` check would get wrong.
    let h = common::harness(pool.clone());
    let cookie = seed_admin(&pool, &h.app).await;
    let m = insert_manga(&pool, "M", None).await;
    let chapter_id = Uuid::new_v4();
    sqlx::query("INSERT INTO chapters (id, manga_id, number, page_count) VALUES ($1, $2, 1, 0)")
        .bind(chapter_id)
        .bind(m)
        .execute(&pool)
        .await
        .unwrap();
    sqlx::query(
        "INSERT INTO pages (chapter_id, page_number, storage_key, content_type) \
         SELECT $1, g, 'k/' || g || '.jpg', 'image/jpeg' FROM generate_series(1, 20000) g",
    )
    .bind(chapter_id)
    .execute(&pool)
    .await
    .unwrap();

    let resp = h
        .app
        .oneshot(common::post_json_with_cookie(
            "/api/v1/admin/storage/backfill",
            serde_json::json!({}),
            &cookie,
        ))
        .await
        .unwrap();
    let body = common::body_json(resp).await;
    assert_eq!(body["missing"].as_i64().unwrap(), 20_000);
    assert_eq!(
        body["more_remaining"].as_bool().unwrap(),
        false,
        "exactly-cap backlog drains in one run; no follow-up needed"
    );
}

#[sqlx::test(migrations = "./migrations")]
async fn backfill_tolerates_missing_blob(pool: PgPool) {
    let h = common::harness(pool.clone());
    let cookie = seed_admin(&pool, &h.app).await;

    // Page row whose blob was never written to storage.
    let m = insert_manga(&pool, "M", None).await;
    let chapter_id = Uuid::new_v4();
    sqlx::query("INSERT INTO chapters (id, manga_id, number, page_count) VALUES ($1, $2, 1, 1)")
        .bind(chapter_id)
        .bind(m)
        .execute(&pool)
        .await
        .unwrap();
    sqlx::query(
        "INSERT INTO pages (chapter_id, page_number, storage_key, content_type) \
         VALUES ($1, 1, 'mangas/x/chapters/y/pages/0001.jpg', 'image/jpeg')",
    )
    .bind(chapter_id)
    .execute(&pool)
    .await
    .unwrap();

    let resp = h
        .app
        .oneshot(common::post_json_with_cookie(
            "/api/v1/admin/storage/backfill",
            serde_json::json!({}),
            &cookie,
        ))
        .await
        .unwrap();
    assert_eq!(resp.status(), StatusCode::OK);
    let body = common::body_json(resp).await;
    assert_eq!(body["pages"].as_i64().unwrap(), 0);
    assert_eq!(body["missing"].as_i64().unwrap(), 1);
    assert_eq!(body["errored"].as_i64().unwrap(), 0);
}