//! Milestone 2: Add, List, Materialize, Gc against a real daemon.

mod support;

use std::path::Path;

use varde_proto::{ErrorCode, MaterializeMode, PinPolicy, Request, ResponseData};

fn add(client: &mut support::Client, path: &Path, recursive: bool) -> (String, u64) {
    let reply = client.request(&Request::Add {
        path: path.display().to_string(),
        recursive,
    });
    assert!(reply.ok, "add failed: {:?}", reply.error);
    match reply.data {
        Some(ResponseData::Added { hash, bytes }) => (hash, bytes),
        other => panic!("unexpected add reply: {other:?}"),
    }
}

fn materialize(
    client: &mut support::Client,
    hash: &str,
    dest: &Path,
    mode: MaterializeMode,
) -> Result<(u64, bool), ErrorCode> {
    let reply = client.request(&Request::Materialize {
        hash: hash.to_string(),
        dest: dest.display().to_string(),
        mode,
    });
    if !reply.ok {
        return Err(reply.error.expect("error body").code);
    }
    match reply.data {
        Some(ResponseData::Materialized { bytes, reflinked }) => Ok((bytes, reflinked)),
        other => panic!("unexpected materialize reply: {other:?}"),
    }
}

#[test]
fn file_round_trips_byte_identical() {
    let daemon = support::spawn_daemon();
    let mut client = support::Client::connect(&daemon.socket);
    let dir = tempfile::tempdir().unwrap();

    let src = dir.path().join("input.bin");
    let payload: Vec<u8> = (0..100_000u32).flat_map(|i| i.to_le_bytes()).collect();
    std::fs::write(&src, &payload).unwrap();

    let (hash, bytes) = add(&mut client, &src, false);
    assert_eq!(bytes, payload.len() as u64);

    let dest = dir.path().join("output.bin");
    let (out_bytes, _) = materialize(&mut client, &hash, &dest, MaterializeMode::Copy).unwrap();
    assert_eq!(out_bytes, payload.len() as u64);
    assert_eq!(
        std::fs::read(&dest).unwrap(),
        payload,
        "bytes differ after round trip"
    );
}

#[test]
fn directory_tree_round_trips() {
    let daemon = support::spawn_daemon();
    let mut client = support::Client::connect(&daemon.socket);
    let dir = tempfile::tempdir().unwrap();

    let src = dir.path().join("tree");
    std::fs::create_dir_all(src.join("sub/deeper")).unwrap();
    std::fs::write(src.join("a.txt"), b"alpha").unwrap();
    std::fs::write(src.join("sub/b.bin"), vec![0u8; 20_000]).unwrap();
    std::fs::write(src.join("sub/deeper/c"), b"").unwrap();

    let (hash, bytes) = add(&mut client, &src, true);
    assert_eq!(bytes, 5 + 20_000);

    let dest = dir.path().join("out");
    let (out_bytes, _) =
        materialize(&mut client, &hash, &dest, MaterializeMode::ReflinkOrCopy).unwrap();
    assert_eq!(out_bytes, bytes);

    for rel in ["a.txt", "sub/b.bin", "sub/deeper/c"] {
        let original = std::fs::read(src.join(rel)).unwrap();
        let copy = std::fs::read(dest.join(rel)).unwrap();
        assert_eq!(original, copy, "{rel} differs after round trip");
    }
}

#[test]
fn directory_without_recursive_is_rejected() {
    let daemon = support::spawn_daemon();
    let mut client = support::Client::connect(&daemon.socket);
    let dir = tempfile::tempdir().unwrap();
    std::fs::write(dir.path().join("f"), b"x").unwrap();

    let reply = client.request(&Request::Add {
        path: dir.path().display().to_string(),
        recursive: false,
    });
    assert!(!reply.ok);
    assert_eq!(reply.error.unwrap().code, ErrorCode::InvalidArgument);
}

#[test]
fn materialize_unknown_hash_is_not_found() {
    let daemon = support::spawn_daemon();
    let mut client = support::Client::connect(&daemon.socket);
    let dir = tempfile::tempdir().unwrap();

    let missing = "0".repeat(64);
    let err = materialize(
        &mut client,
        &missing,
        &dir.path().join("out"),
        MaterializeMode::Copy,
    )
    .unwrap_err();
    assert_eq!(err, ErrorCode::NotFound);
}

#[test]
fn gc_drops_unpinned_and_keeps_pinned() {
    let daemon = support::spawn_daemon();
    let mut client = support::Client::connect(&daemon.socket);
    let dir = tempfile::tempdir().unwrap();

    // A pinned directory tree (root + children + meta must all survive)
    // and an unpinned lone file (must be collected).
    let tree = dir.path().join("tree");
    std::fs::create_dir_all(&tree).unwrap();
    std::fs::write(tree.join("keep.bin"), vec![7u8; 50_000]).unwrap();
    let (kept_root, _) = add(&mut client, &tree, true);

    let loose = dir.path().join("loose.bin");
    std::fs::write(&loose, vec![9u8; 50_000]).unwrap();
    let (doomed, _) = add(&mut client, &loose, false);

    let reply = client.request(&Request::Pin {
        hash: kept_root.clone(),
        policy: PinPolicy::default(),
    });
    assert!(reply.ok, "pin failed: {:?}", reply.error);

    let reply = client.request(&Request::Gc {});
    assert!(reply.ok, "gc failed: {:?}", reply.error);
    match reply.data {
        Some(ResponseData::GcDone { blobs_removed }) => assert!(blobs_removed >= 1),
        other => panic!("unexpected gc reply: {other:?}"),
    }

    // Pinned tree still materializes; loose blob is gone.
    materialize(
        &mut client,
        &kept_root,
        &dir.path().join("out"),
        MaterializeMode::Copy,
    )
    .expect("pinned content must survive gc");
    let err = materialize(
        &mut client,
        &doomed,
        &dir.path().join("out2"),
        MaterializeMode::Copy,
    )
    .unwrap_err();
    assert_eq!(err, ErrorCode::NotFound);

    // Unpinning and collecting again drops the tree too.
    let reply = client.request(&Request::Unpin {
        hash: kept_root.clone(),
    });
    assert!(reply.ok);
    let reply = client.request(&Request::Gc {});
    assert!(reply.ok);
    let err = materialize(
        &mut client,
        &kept_root,
        &dir.path().join("out3"),
        MaterializeMode::Copy,
    )
    .unwrap_err();
    assert_eq!(err, ErrorCode::NotFound);
}

#[test]
fn list_reports_pin_completeness() {
    let daemon = support::spawn_daemon();
    let mut client = support::Client::connect(&daemon.socket);
    let dir = tempfile::tempdir().unwrap();

    let src = dir.path().join("f.bin");
    std::fs::write(&src, vec![1u8; 10_000]).unwrap();
    let (hash, _) = add(&mut client, &src, false);
    let reply = client.request(&Request::Pin {
        hash: hash.clone(),
        policy: PinPolicy { open_lan: true },
    });
    assert!(reply.ok);

    let reply = client.request(&Request::List {});
    assert!(reply.ok);
    match reply.data {
        Some(ResponseData::Pins { pins }) => {
            assert_eq!(pins.len(), 1);
            assert_eq!(pins[0].hash, hash);
            assert!(pins[0].complete);
            assert!(pins[0].policy.open_lan);
            assert_eq!(pins[0].total_bytes, Some(10_000));
        }
        other => panic!("unexpected list reply: {other:?}"),
    }
}

/// Reflink needs store and destination on one filesystem that supports
/// FICLONE. `CARGO_TARGET_TMPDIR` lives under `target/`, so this exercises
/// the real filesystem the repo sits on; on filesystems without reflink
/// the test degrades into asserting the copy fallback works.
#[test]
fn reflink_when_supported() {
    let base = Path::new(env!("CARGO_TARGET_TMPDIR")).join("reflink-test");
    let _ = std::fs::remove_dir_all(&base);
    std::fs::create_dir_all(&base).unwrap();
    let daemon = support::spawn_daemon_at(&base);
    let mut client = support::Client::connect(&daemon.socket);

    let src = base.join("big.bin");
    // Comfortably above the inline threshold so the blob lands as a
    // real file in the store's data dir.
    std::fs::write(&src, vec![42u8; 1_000_000]).unwrap();
    let (hash, _) = add(&mut client, &src, false);

    let dest = base.join("out.bin");
    let (bytes, reflinked) =
        materialize(&mut client, &hash, &dest, MaterializeMode::ReflinkOrCopy).unwrap();
    assert_eq!(bytes, 1_000_000);
    assert_eq!(std::fs::read(&dest).unwrap(), vec![42u8; 1_000_000]);

    if !reflinked {
        eprintln!("SKIP: filesystem does not support reflink; copy fallback verified instead");
        return;
    }
    // Forced copy mode must not reflink.
    let dest2 = base.join("out2.bin");
    let (_, reflinked2) = materialize(&mut client, &hash, &dest2, MaterializeMode::Copy).unwrap();
    assert!(!reflinked2, "copy mode must never reflink");

    drop(daemon);
    let _ = std::fs::remove_dir_all(&base);
}