//! Integration tests for the producer half — the open-op path
//! (establisher + pump handler + registration) over the duplex
//! harness, ported from the reverse POC's suite (16 tests rode the
//! topology) with the dial closure standing in for real sockets.
//!
//! Covered: establishment success + the typed-error table
//! (`unknown_resource` / `dial_failed` / `FORBIDDEN`), the plan flow
//! under same-resource concurrency (R-01 — no handoff race), the
//! per-call opener identity (CF-006 witness), late-registration
//! visibility (W2), pump round-trip through `pump_bidi` (R-02 — the
//! wrapper-managed pump, no spawn-and-forget), and out-of-band
//! `channel/close`.

mod harness;

use std::sync::Arc;

use alkcall::protocol::wire::CallError;
use alktunnels::params::{Substrate, TUNNEL_OPEN_SCOPE};
use alktunnels::producer::ResourceRegistry;

use harness::{echo_dial, failing_dial, wire, wire_with, Topology, TEST_AUTH_TOKEN};

fn params(resource: &str) -> alktunnels::params::TunnelParams {
    alktunnels::params::TunnelParams {
        resource: resource.to_string(),
        substrate: Substrate::Tcp,
    }
}

/// Call the producer's open op on channel 0 (the consumer's surface),
/// returning the wire `CallError` on failure.
async fn call_open(
    topo: &Topology,
    input: serde_json::Value,
    auth_token: Option<&str>,
) -> Result<serde_json::Value, CallError> {
    let mut payload = serde_json::json!({
        "operationId": "channels/tunnel/sub",
        "input": input,
    });
    if let Some(token) = auth_token {
        payload["auth_token"] = serde_json::Value::String(token.to_string());
    }
    let response = topo.consumer_call.call_with_payload(payload).await;
    response.result
}

async fn call_open_params(
    topo: &Topology,
    p: &alktunnels::params::TunnelParams,
    auth_token: Option<&str>,
) -> Result<serde_json::Value, CallError> {
    call_open(
        topo,
        serde_json::json!({
            "resource": p.resource,
            "substrate": match p.substrate {
                Substrate::Tcp => "tcp",
                Substrate::Udp => "udp",
                Substrate::Unix => "unix",
            },
        }),
        auth_token,
    )
    .await
}

/// Adopt the producer-allocated channel and pump it against in-process
/// halves (the consumer-side data plane — the session's take_halves
/// shape, driven manually until the consumer session task lands).
async fn adopt_and_pump(
    topo: &Topology,
    channel_id: u32,
) -> (
    tokio::io::ReadHalf<tokio::io::DuplexStream>,
    tokio::io::WriteHalf<tokio::io::DuplexStream>,
    tokio::task::JoinHandle<(u64, u64)>,
) {
    let (send, recv) = topo
        .consumer_manager
        .adopt_channel(channel_id, "alk/tunnel", None)
        .await
        .expect("adopt producer-allocated channel");
    let bidi = alkcall::core::types::BiStream::from_joined(recv, send);
    let (channel_end, local_end) = tokio::io::duplex(64 * 1024);
    let (c_read, c_write) = tokio::io::split(channel_end);
    let pump = tokio::spawn(alkcall::channels::pump::pump_bidi(bidi, c_read, c_write));
    let (l_read, l_write) = tokio::io::split(local_end);
    (l_read, l_write, pump)
}

/// Only channel 0 (the pre-negotiated call channel) may remain — a
/// failed open leaves no data channel on either side (the
/// phantom-channel property).
fn no_data_channels(topo: &Topology) -> bool {
    let consumer = topo.consumer_manager.channel_ids();
    let producer = topo.producer.manager().channel_ids();
    consumer.iter().all(|&id| id == 0) && producer.iter().all(|&id| id == 0)
}

#[tokio::test]
async fn open_round_trips_through_pump_bidi() {
    let registry = ResourceRegistry::new();
    registry
        .register("echo", Substrate::Tcp, "in-process")
        .await;
    let topo = wire(registry, echo_dial()).await;

    let out = call_open_params(&topo, &params("echo"), None)
        .await
        .expect("open must succeed");
    let channel_id = out["channel_id"].as_u64().expect("channel_id") as u32;
    assert!(topo.producer.manager().has_channel(channel_id));

    let (mut read, mut write, pump) = adopt_and_pump(&topo, channel_id).await;
    use tokio::io::{AsyncReadExt, AsyncWriteExt};
    write.write_all(b"ping").await.expect("write");
    write.flush().await.expect("flush");
    let mut buf = vec![0u8; 4];
    tokio::time::timeout(std::time::Duration::from_secs(5), read.read_exact(&mut buf))
        .await
        .expect("round trip timed out")
        .expect("read");
    assert_eq!(&buf, b"ping");

    // EOF propagates: closing the local write half shuts the loop
    // down through both pumps (the two-pump contract), and the
    // wrapper reaps the producer-side channel on completion (R-02).
    drop(write);
    drop(read);
    let (c2p, p2c) = tokio::time::timeout(std::time::Duration::from_secs(5), pump)
        .await
        .expect("pump completion timed out")
        .expect("pump task");
    assert!(c2p > 0 && p2c > 0, "both pumps moved bytes: {c2p}, {p2c}");
    tokio::time::sleep(std::time::Duration::from_millis(100)).await;
    assert!(
        !topo.producer.manager().has_channel(channel_id),
        "wrapper reaped the producer-side channel after pump completion"
    );
}

#[tokio::test]
async fn unknown_resource_is_typed_and_leaves_no_channel() {
    let registry = ResourceRegistry::new();
    registry
        .register("echo", Substrate::Tcp, "in-process")
        .await;
    let topo = wire(registry, echo_dial()).await;

    let err = call_open_params(&topo, &params("ghost"), None)
        .await
        .expect_err("unknown resource must fail the open");
    assert_eq!(err.code, "channel:open_failed");
    assert_eq!(establishment_reason_of(&err), Some("unknown_resource"));
    assert!(no_data_channels(&topo));
}

fn establishment_reason_of(err: &CallError) -> Option<&str> {
    err.details
        .as_ref()
        .and_then(|d| d.get("reason"))
        .and_then(|r| r.as_str())
}

#[tokio::test]
async fn dial_failure_is_typed_and_leaves_no_channel() {
    let registry = ResourceRegistry::new();
    registry
        .register("dead", Substrate::Tcp, "unreachable")
        .await;
    let topo = wire(registry, failing_dial("no route to target")).await;

    let err = call_open_params(&topo, &params("dead"), None)
        .await
        .expect_err("failed dial must fail the open");
    assert_eq!(err.code, "channel:open_failed");
    assert_eq!(establishment_reason_of(&err), Some("dial_failed"));
    assert!(no_data_channels(&topo));
}

#[tokio::test]
async fn open_denied_without_any_identity() {
    let registry = ResourceRegistry::new();
    registry
        .register("echo", Substrate::Tcp, "in-process")
        .await;
    let topo = wire_with(
        registry,
        echo_dial(),
        None,
        None,
        Arc::new(alkcall::core::auth::NoopIdentityProvider),
    )
    .await;

    let err = call_open_params(&topo, &params("echo"), None)
        .await
        .expect_err("identity-less open must be denied");
    assert_eq!(err.code, "FORBIDDEN");
    assert!(no_data_channels(&topo));
}

#[tokio::test]
async fn open_on_transport_identity_alone() {
    // CF-005 (b): the transport identity (set before dialing)
    // propagates to the serving dispatch and authorizes the scope
    // gate. No token payload at all.
    let registry = ResourceRegistry::new();
    registry
        .register("echo", Substrate::Tcp, "in-process")
        .await;
    let topo = wire(registry, echo_dial()).await;

    let out = call_open_params(&topo, &params("echo"), None)
        .await
        .expect("transport-identity open must be authorized");
    assert!(out["channel_id"].is_u64());

    // CF-006: the establisher's per-call auth carried the END CALLER's
    // identity (the consumer), not a synthetic install-time value.
    let witness = topo.identity_witness.lock().await.clone();
    assert_eq!(
        witness.as_deref(),
        Some("consumer"),
        "establisher saw the per-call opener identity (CF-006)"
    );
}

#[tokio::test]
async fn open_token_overrides_transport_identity() {
    // CF-005 precedence: the payload token wins. The provider resolves
    // the scoped token to the consumer identity — the witness proves
    // the establisher saw it end-to-end.
    let registry = ResourceRegistry::new();
    registry
        .register("echo", Substrate::Tcp, "in-process")
        .await;
    let topo = wire_with(
        registry,
        echo_dial(),
        None,
        None,
        Arc::new(harness::TestIdProvider),
    )
    .await;

    let out = call_open_params(&topo, &params("echo"), Some(TEST_AUTH_TOKEN))
        .await
        .expect("token open authorized");
    assert!(out["channel_id"].is_u64());
    let witness = topo.identity_witness.lock().await.clone();
    assert_eq!(witness.as_deref(), Some("consumer"));
}

#[tokio::test]
async fn concurrent_opens_same_resource_no_plan_race() {
    // The R-01 plan flow under concurrency: two opens of the SAME
    // resource — the establisher returns each dialed handle via ITS
    // plan; no handoff map to race. Each round-trips its own marker.
    let registry = ResourceRegistry::new();
    registry
        .register("echo", Substrate::Tcp, "in-process")
        .await;
    let topo = wire(registry, echo_dial()).await;

    use tokio::io::{AsyncReadExt, AsyncWriteExt};

    let mut sessions = Vec::new();
    for i in 0..2 {
        let out = call_open_params(&topo, &params("echo"), None)
            .await
            .expect("open must succeed");
        let channel_id = out["channel_id"].as_u64().unwrap() as u32;
        let (mut read, mut write, _pump) = adopt_and_pump(&topo, channel_id).await;
        let msg = format!("marker {i}");
        write.write_all(msg.as_bytes()).await.expect("write");
        write.flush().await.expect("flush");
        let mut buf = vec![0u8; msg.len()];
        tokio::time::timeout(std::time::Duration::from_secs(5), read.read_exact(&mut buf))
            .await
            .expect("round trip")
            .expect("read");
        assert_eq!(buf, msg.as_bytes());
        sessions.push(channel_id);
    }
    assert_ne!(sessions[0], sessions[1]);
}

#[tokio::test]
async fn late_registration_is_visible() {
    // W2: the harness registers the openable AFTER
    // from_connection_with_serving. If the dispatcher cached
    // registrations, opens would fail with unknown-operation — the
    // successful opens elsewhere prove it; assert registry state too.
    let registry = ResourceRegistry::new();
    registry
        .register("late", Substrate::Tcp, "in-process")
        .await;
    let topo = wire(registry, echo_dial()).await;
    assert!(topo
        .producer_registry
        .registration("channels/tunnel/sub")
        .is_some());
}

#[tokio::test]
async fn schema_rejects_unknown_substrate_loudly() {
    // The registry schema-validates input before the establisher
    // (ADR-001's loud posture): an unknown substrate value is a schema
    // failure, not a silent pass-through.
    let registry = ResourceRegistry::new();
    registry
        .register("echo", Substrate::Tcp, "in-process")
        .await;
    let topo = wire(registry, echo_dial()).await;

    let err = call_open(
        &topo,
        serde_json::json!({"resource": "echo", "substrate": "sctp"}),
        None,
    )
    .await
    .expect_err("unknown substrate must fail the open");
    assert_eq!(err.code, "INVALID_INPUT");
}

#[tokio::test]
async fn producer_outbound_calls_still_resolve_while_serving() {
    // ADR-022 §2 both-sides sanity: the producer is the connect side
    // AND the serving side; its outbound calling still resolves while
    // it serves tunnel opens.
    let registry = ResourceRegistry::new();
    registry
        .register("echo", Substrate::Tcp, "in-process")
        .await;
    let topo = wire(registry, echo_dial()).await;

    let response = topo
        .producer
        .call_open_op("consumer/serves/nothing", serde_json::json!({}))
        .await;
    assert!(
        response.result.is_err(),
        "consumer serves nothing; the point is the reply RESOLVED"
    );
}

#[tokio::test]
async fn registry_lookup_respects_substrate_key() {
    // The registry is keyed by (resource, substrate): a resource
    // produced for TCP is unknown for UDP — the same name on a
    // different substrate is a different resource (ADR-001).
    let registry = ResourceRegistry::new();
    registry.register("svc", Substrate::Tcp, "in-process").await;
    let topo = wire(registry, failing_dial("unreachable")).await;

    let mut p = params("svc");
    p.substrate = Substrate::Udp;
    let err = call_open_params(&topo, &p, None)
        .await
        .expect_err("udp lookup of a tcp resource must miss");
    assert_eq!(establishment_reason_of(&err), Some("unknown_resource"));
}

/// Type-shape assertions kept for harness parity.
#[allow(dead_code)]
fn type_assertions() {
    let _dial = echo_dial();
    let _scope: &str = TUNNEL_OPEN_SCOPE;
}