//! End-to-end dispatcher tests — one per trigger kind (v1.1.5 follow-up,
//! landed in v1.1.6). Each test wires the full all-in-one app via
//! `build_app` (which spawns the real dispatcher + cron scheduler +
//! executor), creates an app + a logging handler script + a trigger,
//! causes the originating event, and polls for the handler's side effect.
//!
//! ## Gating
//!
//! These need a Postgres reachable via `DATABASE_URL`. They follow the
//! `schema_snapshot` pattern (NOT `#[ignore]`): when `DATABASE_URL` is
//! unset the test prints a notice and returns early, so plain
//! `cargo test` stays green locally while CI (which sets `DATABASE_URL`)
//! runs them.
//!
//! ## How "the handler fired" is observed
//!
//! The dispatcher does not write `execution_log` rows for trigger
//! handlers, so each handler instead records its `ctx.event` into a KV
//! marker (`collection = "e2e_markers"`, which no trigger watches — no
//! recursion). The test polls `kv_entries` for that marker and asserts
//! the event shape. See HANDBACK §deviations for why this lives in
//! `picloud/tests/` rather than `manager-core/tests/` (build_app lives in
//! the `picloud` crate) and for the `dead_letter` reinterpretation.

#![allow(clippy::needless_pass_by_value)]

use std::time::Duration;

use axum_test::TestServer;
use serde_json::{json, Value};
use sqlx::postgres::PgPoolOptions;
use sqlx::PgPool;
use uuid::Uuid;

/// Connect + migrate, or return `None` (printing a skip notice) when
/// `DATABASE_URL` is unset — mirrors `schema_snapshot.rs`.
async fn pool_or_skip() -> Option<PgPool> {
    let Ok(url) = std::env::var("DATABASE_URL") else {
        eprintln!("dispatcher_e2e: DATABASE_URL unset — skipping");
        return None;
    };
    let pool = PgPoolOptions::new()
        .max_connections(5)
        .connect(&url)
        .await
        .expect("connect to DATABASE_URL");
    sqlx::migrate!("../manager-core/migrations")
        .run(&pool)
        .await
        .expect("apply migrations");
    Some(pool)
}

/// Build the app over the shared pool with a uniquely-named owner admin,
/// log in, and create a fresh app. `suffix` must be unique per test (the
/// pool is shared, so names must not collide).
async fn server_for(pool: PgPool, suffix: &str) -> (TestServer, String) {
    use picloud_manager_core::auth::hash_password;
    use picloud_shared::InstanceRole;

    let unique = format!("{suffix}-{}", Uuid::new_v4().simple());
    let auth = picloud::AuthDeps::from_pool(pool.clone());
    let username = format!("e2e-{unique}");
    let hash = hash_password("pw").expect("hash");
    auth.users
        .create(&username, &hash, InstanceRole::Owner, None)
        .await
        .expect("seed admin");

    let app = picloud::build_app(
        pool,
        auth,
        picloud_shared::MasterKey::from_bytes([0x42u8; 32]),
    )
    .await
    .expect("build_app");
    let mut server = TestServer::new(app).expect("TestServer");
    let resp = server
        .post("/api/v1/admin/auth/login")
        .json(&json!({ "username": username, "password": "pw" }))
        .await;
    resp.assert_status_ok();
    let token = resp.json::<Value>()["token"]
        .as_str()
        .expect("login token")
        .to_string();
    server.add_header("authorization", format!("Bearer {token}"));

    // A fresh app keeps each test's KV / events isolated from siblings.
    let slug = format!("e2e-{unique}");
    let created: Value = server
        .post("/api/v1/admin/apps")
        .json(&json!({ "slug": slug, "name": slug }))
        .await
        .json();
    let app_id = created["id"].as_str().expect("app id").to_string();
    (server, app_id)
}

async fn create_script(server: &TestServer, app_id: &str, name: &str, source: &str) -> String {
    let created: Value = server
        .post("/api/v1/admin/scripts")
        .json(&json!({ "app_id": app_id, "name": name, "source": source }))
        .await
        .json();
    created["id"].as_str().expect("script id").to_string()
}

/// A handler that records its `ctx.event` into a KV marker the test can
/// observe. The marker collection is watched by no trigger.
const MARKER_HANDLER: &str = r#"
    let e = ctx.event;
    kv::collection("e2e_markers").set("marker", e);
    #{ ok: true }
"#;

/// Poll the marker KV key until present (or ~10s timeout).
async fn poll_marker(pool: &PgPool, app_id: &str) -> Option<Value> {
    poll_marker_n(pool, app_id, 100).await
}

/// Poll the marker KV key for `iters` × 100ms.
async fn poll_marker_n(pool: &PgPool, app_id: &str, iters: u32) -> Option<Value> {
    let app_uuid = Uuid::parse_str(app_id).expect("app uuid");
    for _ in 0..iters {
        let row: Option<(Value,)> = sqlx::query_as(
            "SELECT value FROM kv_entries \
             WHERE app_id = $1 AND collection = 'e2e_markers' AND key = 'marker'",
        )
        .bind(app_uuid)
        .fetch_optional(pool)
        .await
        .expect("query marker");
        if let Some((value,)) = row {
            return Some(value);
        }
        tokio::time::sleep(Duration::from_millis(100)).await;
    }
    None
}

async fn execute(server: &TestServer, script_id: &str) {
    server
        .post(&format!("/api/v1/execute/{script_id}"))
        .json(&json!({}))
        .await
        .assert_status_ok();
}

#[tokio::test]
async fn dispatcher_delivers_kv_to_handler() {
    let Some(pool) = pool_or_skip().await else {
        return;
    };
    let (server, app_id) = server_for(pool.clone(), "kv").await;

    let handler = create_script(&server, &app_id, "kv-handler", MARKER_HANDLER).await;
    server
        .post(&format!("/api/v1/admin/apps/{app_id}/triggers/kv"))
        .json(&json!({ "script_id": handler, "collection_glob": "src" }))
        .await
        .assert_status(axum::http::StatusCode::CREATED);

    let source = create_script(
        &server,
        &app_id,
        "kv-source",
        r#"kv::collection("src").set("k", 42); #{ ok: true }"#,
    )
    .await;
    execute(&server, &source).await;

    let event = poll_marker(&pool, &app_id).await.expect("kv handler fired");
    assert_eq!(event["source"], "kv");
    assert_eq!(event["op"], "insert");
    assert_eq!(event["kv"]["collection"], "src");
    assert_eq!(event["kv"]["key"], "k");
}

#[tokio::test]
async fn dispatcher_delivers_docs_to_handler() {
    let Some(pool) = pool_or_skip().await else {
        return;
    };
    let (server, app_id) = server_for(pool.clone(), "docs").await;

    let handler = create_script(&server, &app_id, "docs-handler", MARKER_HANDLER).await;
    server
        .post(&format!("/api/v1/admin/apps/{app_id}/triggers/docs"))
        .json(&json!({ "script_id": handler, "collection_glob": "src" }))
        .await
        .assert_status(axum::http::StatusCode::CREATED);

    let source = create_script(
        &server,
        &app_id,
        "docs-source",
        r#"docs::collection("src").create(#{ x: 1 }); #{ ok: true }"#,
    )
    .await;
    execute(&server, &source).await;

    let event = poll_marker(&pool, &app_id)
        .await
        .expect("docs handler fired");
    assert_eq!(event["source"], "docs");
    assert_eq!(event["op"], "create");
    assert_eq!(event["docs"]["collection"], "src");
}

#[tokio::test]
async fn dispatcher_delivers_cron_to_handler() {
    let Some(pool) = pool_or_skip().await else {
        return;
    };
    let (server, app_id) = server_for(pool.clone(), "cron").await;

    let handler = create_script(&server, &app_id, "cron-handler", MARKER_HANDLER).await;
    // Fire every second (6-field cron, seconds-resolution).
    server
        .post(&format!("/api/v1/admin/apps/{app_id}/triggers/cron"))
        .json(&json!({ "script_id": handler, "schedule": "* * * * * *", "timezone": "UTC" }))
        .await
        .assert_status(axum::http::StatusCode::CREATED);

    // No source — the scheduler enqueues the due tick on its own. The
    // scheduler skips its first tick and then ticks every
    // PICLOUD_CRON_TICK_INTERVAL_MS (default 30s), so poll past that
    // (set the env var lower to speed CI up if desired).
    let event = poll_marker_n(&pool, &app_id, 450)
        .await
        .expect("cron handler fired");
    assert_eq!(event["source"], "cron");
    assert_eq!(event["op"], "tick");
    assert_eq!(event["cron"]["timezone"], "UTC");
}

#[tokio::test]
async fn dispatcher_delivers_files_to_handler() {
    let Some(pool) = pool_or_skip().await else {
        return;
    };
    let (server, app_id) = server_for(pool.clone(), "files").await;

    let handler = create_script(&server, &app_id, "files-handler", MARKER_HANDLER).await;
    server
        .post(&format!("/api/v1/admin/apps/{app_id}/triggers/files"))
        .json(&json!({ "script_id": handler, "collection_glob": "src" }))
        .await
        .assert_status(axum::http::StatusCode::CREATED);

    let source = create_script(
        &server,
        &app_id,
        "files-source",
        r#"
            let data = base64::decode("aGk=");
            files::collection("src").create(#{ name: "f.txt", content_type: "text/plain", data: data });
            #{ ok: true }
        "#,
    )
    .await;
    execute(&server, &source).await;

    let event = poll_marker(&pool, &app_id)
        .await
        .expect("files handler fired");
    assert_eq!(event["source"], "files");
    assert_eq!(event["op"], "create");
    assert_eq!(event["files"]["collection"], "src");
    assert_eq!(event["files"]["name"], "f.txt");
}

#[tokio::test]
async fn dispatcher_delivers_pubsub_to_handler() {
    let Some(pool) = pool_or_skip().await else {
        return;
    };
    let (server, app_id) = server_for(pool.clone(), "pubsub").await;

    let handler = create_script(&server, &app_id, "pubsub-handler", MARKER_HANDLER).await;
    server
        .post(&format!("/api/v1/admin/apps/{app_id}/triggers/pubsub"))
        .json(&json!({ "script_id": handler, "topic_pattern": "e2e.topic" }))
        .await
        .assert_status(axum::http::StatusCode::CREATED);

    let source = create_script(
        &server,
        &app_id,
        "pubsub-source",
        r#"pubsub::publish_durable("e2e.topic", #{ hello: 1 }); #{ ok: true }"#,
    )
    .await;
    execute(&server, &source).await;

    let event = poll_marker(&pool, &app_id)
        .await
        .expect("pubsub handler fired");
    assert_eq!(event["source"], "pubsub");
    assert_eq!(event["op"], "publish");
    assert_eq!(event["pubsub"]["topic"], "e2e.topic");
    assert_eq!(event["pubsub"]["message"]["hello"], 1);
}

/// Count dead_letters rows for an app.
async fn dead_letter_count(pool: &PgPool, app_id: &str) -> i64 {
    let app_uuid = Uuid::parse_str(app_id).unwrap();
    sqlx::query_scalar("SELECT COUNT(*) FROM dead_letters WHERE app_id = $1")
        .bind(app_uuid)
        .fetch_one(pool)
        .await
        .expect("count dead_letters")
}

async fn poll_dead_letter_count(pool: &PgPool, app_id: &str, want: i64) -> i64 {
    let mut count = 0;
    for _ in 0..100 {
        count = dead_letter_count(pool, app_id).await;
        if count >= want {
            break;
        }
        tokio::time::sleep(Duration::from_millis(100)).await;
    }
    count
}

/// Register a failing KV trigger on `dlsrc` (single attempt → immediate
/// dead-letter) and a `dead_letter` trigger pointing at the marker
/// handler, then cause the originating KV event. Returns when set up.
async fn setup_dead_letter(server: &TestServer, app_id: &str, dl_handler: &str) {
    let failing = create_script(server, app_id, "dl-failing", r#"throw "boom";"#).await;
    server
        .post(&format!("/api/v1/admin/apps/{app_id}/triggers/kv"))
        .json(&json!({
            "script_id": failing,
            "collection_glob": "dlsrc",
            "retry_max_attempts": 1,
            "retry_base_ms": 0
        }))
        .await
        .assert_status(axum::http::StatusCode::CREATED);
    // The dead_letter trigger (no filters → matches any dead-letter).
    server
        .post(&format!("/api/v1/admin/apps/{app_id}/triggers/dead_letter"))
        .json(&json!({ "script_id": dl_handler }))
        .await
        .assert_status(axum::http::StatusCode::CREATED);

    let source = create_script(
        server,
        app_id,
        "dl-source",
        r#"kv::collection("dlsrc").set("k", 1); #{ ok: true }"#,
    )
    .await;
    execute(server, source.as_str()).await;
}

#[tokio::test]
async fn dispatcher_delivers_dead_letter_to_handler() {
    // v1.1.7: the dead-letter fan-out is now wired
    // (`dispatcher::handle_failure` → `list_matching_dead_letter` →
    // outbox). This asserts BOTH that the `dead_letters` row is written
    // AND that the registered `dead_letter`-kind handler actually fires
    // (it was silently non-functional v1.1.1–v1.1.6).
    let Some(pool) = pool_or_skip().await else {
        return;
    };
    let (server, app_id) = server_for(pool.clone(), "dl").await;
    let handler = create_script(&server, &app_id, "dl-handler", MARKER_HANDLER).await;
    setup_dead_letter(&server, &app_id, &handler).await;

    // Row written.
    assert!(
        poll_dead_letter_count(&pool, &app_id, 1).await > 0,
        "a dead-letter row should have been produced"
    );
    // Handler fired.
    let event = poll_marker(&pool, &app_id)
        .await
        .expect("dead-letter handler fired");
    assert_eq!(event["source"], "dead_letter");
}

#[tokio::test]
async fn dispatcher_delivers_dead_letter_to_handler_actually_fires() {
    // Focused on the handler-fire side: the marker handler receives a
    // fully-shaped dead-letter event (the original KV event nested under
    // `ctx.event.dead_letter.original`, plus the failure metadata).
    let Some(pool) = pool_or_skip().await else {
        return;
    };
    let (server, app_id) = server_for(pool.clone(), "dlfire").await;
    let handler = create_script(&server, &app_id, "dl-handler", MARKER_HANDLER).await;
    setup_dead_letter(&server, &app_id, &handler).await;

    let event = poll_marker(&pool, &app_id)
        .await
        .expect("dead-letter handler fired");
    assert_eq!(event["source"], "dead_letter");
    // The original KV event is nested verbatim.
    assert_eq!(event["dead_letter"]["original"]["source"], "kv");
    assert_eq!(
        event["dead_letter"]["original"]["kv"]["collection"],
        "dlsrc"
    );
    // Failure metadata is present.
    assert!(event["dead_letter"]["last_error"]
        .as_str()
        .unwrap()
        .contains("boom"));
    assert!(event["dead_letter"]["attempts"].as_i64().unwrap() >= 1);
}

#[tokio::test]
async fn dead_letter_source_filter_excludes_nonmatching() {
    // `list_matching_dead_letter` filters by source (among trigger_id /
    // script_id). A dead_letter trigger whose `source_filter` is "docs"
    // must NOT fire for a "kv"-sourced dead-letter — the row is still
    // written, but no handler delivery is enqueued.
    let Some(pool) = pool_or_skip().await else {
        return;
    };
    let (server, app_id) = server_for(pool.clone(), "dlfilter").await;
    let handler = create_script(&server, &app_id, "dl-handler", MARKER_HANDLER).await;

    let failing = create_script(&server, &app_id, "dl-failing", r#"throw "boom";"#).await;
    server
        .post(&format!("/api/v1/admin/apps/{app_id}/triggers/kv"))
        .json(&json!({
            "script_id": failing,
            "collection_glob": "dlsrc",
            "retry_max_attempts": 1,
            "retry_base_ms": 0
        }))
        .await
        .assert_status(axum::http::StatusCode::CREATED);
    // Filter to a different source so this handler must NOT match.
    server
        .post(&format!("/api/v1/admin/apps/{app_id}/triggers/dead_letter"))
        .json(&json!({ "script_id": handler, "source_filter": "docs" }))
        .await
        .assert_status(axum::http::StatusCode::CREATED);

    let source = create_script(
        &server,
        &app_id,
        "dl-source",
        r#"kv::collection("dlsrc").set("k", 1); #{ ok: true }"#,
    )
    .await;
    execute(&server, &source).await;

    // The dead-letter row is written…
    assert!(poll_dead_letter_count(&pool, &app_id, 1).await >= 1);
    // …but the source-filtered handler never fires.
    let marker = poll_marker_n(&pool, &app_id, 8).await;
    assert!(
        marker.is_none(),
        "source_filter='docs' must not fire for a kv dead-letter"
    );
}

#[tokio::test]
async fn dead_letter_handler_failure_does_not_recurse() {
    // Recursion-stop (design notes §4): a dead_letter handler that itself
    // throws must NOT produce a second dead-letter row. The
    // `is_dead_letter_handler` short-circuit annotates the original row
    // and drops the outbox row without re-dead-lettering.
    let Some(pool) = pool_or_skip().await else {
        return;
    };
    let (server, app_id) = server_for(pool.clone(), "dlrec").await;
    // The DL handler itself throws.
    let throwing = create_script(&server, &app_id, "dl-throws", r#"throw "handler boom";"#).await;
    setup_dead_letter(&server, &app_id, &throwing).await;

    // One dead-letter row appears (the original). Give the throwing
    // handler time to run + (not) recurse, then confirm the count stayed
    // at exactly 1.
    assert!(poll_dead_letter_count(&pool, &app_id, 1).await >= 1);
    tokio::time::sleep(Duration::from_millis(800)).await;
    assert_eq!(
        dead_letter_count(&pool, &app_id).await,
        1,
        "a failing dead-letter handler must not create a new dead-letter row"
    );
}