//! Worktree-manager integration tests against a real `git` binary and a
//! tmpdir-backed source repo.

mod common;

use std::path::PathBuf;
use std::process::Command;

use common::init_repo;
use maestro_daemon::worktree::WorktreeManager;
use tempfile::TempDir;

fn worktree_branches(repo: &PathBuf) -> Vec<String> {
    let out = Command::new("git")
        .arg("-C")
        .arg(repo)
        .args(["worktree", "list", "--porcelain"])
        .output()
        .expect("git worktree list");
    assert!(out.status.success());
    let s = String::from_utf8_lossy(&out.stdout);
    s.lines()
        .filter_map(|l| l.strip_prefix("branch refs/heads/").map(String::from))
        .collect()
}

#[test]
fn add_creates_worktree_on_new_branch() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let wt_root = TempDir::new().unwrap();
    let mgr = WorktreeManager::new(Some(wt_root.path().to_path_buf()));

    let path = mgr.add_new(&repo, "feat/example").expect("add worktree");
    assert!(path.exists());
    assert!(path.join("README").exists());
    assert!(path.starts_with(wt_root.path()));

    let branches = worktree_branches(&repo);
    assert!(branches.iter().any(|b| b == "feat/example"), "{branches:?}");
}

#[test]
fn add_places_worktree_inside_the_base_repo_by_default() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    // No override: the worktree must land where the repository keeps its
    // own worktrees (#56), not under some daemon state dir.
    let mgr = WorktreeManager::new(None);

    let path = mgr.add_new(&repo, "feat/example").expect("add worktree");
    assert_eq!(path, repo.join("worktrees").join("feat").join("example"));
    assert!(path.exists());
    assert!(path.join("README").exists());

    let branches = worktree_branches(&repo);
    assert!(branches.iter().any(|b| b == "feat/example"), "{branches:?}");
}

#[test]
fn worktree_root_override_redirects_placement() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let wt_root = TempDir::new().unwrap();
    let mgr = WorktreeManager::new(Some(wt_root.path().to_path_buf()));

    // The repo's basename sits between the root and the branch slug, so two
    // repos spawning the same branch name don't target one directory.
    let repo_name = repo.file_name().unwrap();
    let path = mgr.add_new(&repo, "feat/example").expect("add worktree");
    // The override root disambiguates same-named checkouts with a digest of
    // the full repo path, and the branch keeps its own shape.
    // <root>/<repo basename>-<digest>/feat/example
    let prefix = format!("{}-", repo_name.to_string_lossy());
    let repo_dir_name = path
        .strip_prefix(wt_root.path())
        .unwrap()
        .components()
        .next()
        .unwrap();
    assert!(
        repo_dir_name
            .as_os_str()
            .to_string_lossy()
            .starts_with(&prefix),
        "{path:?}"
    );
    assert!(path.ends_with("feat/example"), "{path:?}");
    assert!(path.exists());
}

#[test]
fn existing_directory_at_target_path_is_an_error_carrying_the_path() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    // A predictable path means collisions are possible; they must be
    // reported, never silently relocated.
    std::fs::create_dir_all(repo.join("worktrees").join("feat").join("collide")).unwrap();

    let mgr = WorktreeManager::new(None);
    let err = mgr.add_new(&repo, "feat/collide").unwrap_err();
    let msg = format!("{err}");
    assert!(
        msg.contains(
            repo.join("worktrees")
                .join("feat")
                .join("collide")
                .to_str()
                .unwrap()
        ),
        "{msg}"
    );
}

#[test]
fn add_twice_generates_distinct_paths() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let wt_root = TempDir::new().unwrap();
    let mgr = WorktreeManager::new(Some(wt_root.path().to_path_buf()));

    let p1 = mgr.add_new(&repo, "feat/a").expect("add a");
    let p2 = mgr.add_new(&repo, "feat/b").expect("add b");
    assert_ne!(p1, p2);
    assert!(p1.exists());
    assert!(p2.exists());
}

#[test]
fn remove_prunes_worktree() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let wt_root = TempDir::new().unwrap();
    let mgr = WorktreeManager::new(Some(wt_root.path().to_path_buf()));

    let path = mgr.add_new(&repo, "feat/gone").expect("add");
    assert!(path.exists());

    mgr.remove(&repo, &path).expect("remove");
    assert!(!path.exists());

    let branches = worktree_branches(&repo);
    // The branch itself still exists, but the worktree should be gone — only
    // the base repo's main branch should show in `worktree list`.
    assert_eq!(branches, vec!["main".to_string()]);
}

#[test]
fn add_existing_checks_out_branch_without_creating_it() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    // Pre-create the branch with its own commit so we can tell a checkout
    // from an accidental `-b`.
    let created = Command::new("git")
        .arg("-C")
        .arg(&repo)
        .args(["checkout", "-q", "-b", "feat/dup"])
        .status()
        .unwrap();
    assert!(created.success());
    std::fs::write(repo.join("FEATURE"), b"dup\n").unwrap();
    let staged = Command::new("git")
        .arg("-C")
        .arg(&repo)
        .args(["add", "."])
        .status()
        .unwrap();
    assert!(staged.success());
    let committed = Command::new("git")
        .arg("-C")
        .arg(&repo)
        .args(["commit", "-q", "-am", "wip"])
        .status()
        .unwrap();
    assert!(committed.success());
    let back = Command::new("git")
        .arg("-C")
        .arg(&repo)
        .args(["checkout", "-q", "main"])
        .status()
        .unwrap();
    assert!(back.success());

    let wt_root = TempDir::new().unwrap();
    let mgr = WorktreeManager::new(Some(wt_root.path().to_path_buf()));

    let path = mgr.add_existing(&repo, "feat/dup").expect("add existing");
    assert!(path.exists());
    assert!(path.join("README").exists());

    // The branch set is unchanged: `feat/dup` was checked out, not recreated.
    let branches = worktree_branches(&repo);
    let mut sorted = branches.clone();
    sorted.sort();
    assert_eq!(
        sorted,
        vec!["feat/dup".to_string(), "main".to_string()],
        "{branches:?}"
    );
}

#[test]
fn remove_refuses_worktree_with_uncommitted_changes() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let mgr = WorktreeManager::new(None);
    let path = mgr.add_new(&repo, "feat/dirty").expect("add");
    std::fs::write(path.join("README"), b"unsaved edits\n").unwrap();

    mgr.remove(&repo, &path)
        .expect_err("dirty worktree must be refused");
    assert!(path.exists(), "guarded worktree must stay on disk");

    // Committing it makes removal safe: `worktree remove` keeps
    // `refs/heads/feat/dirty`, so the work is still reachable. Refusing here
    // instead would make every unpushed branch a one-shot, since the path is
    // deterministic and the leftover tree blocks the next spawn (#56 review).
    run_git(&path, &["add", "."]);
    run_git(&path, &["commit", "-q", "-m", "saved"]);

    mgr.remove(&repo, &path).expect("committed work can go");
    assert!(!path.exists());
    assert!(
        worktree_branches(&repo).contains(&"main".to_string()),
        "the branch survives removal"
    );
    let branches = String::from_utf8(
        Command::new("git")
            .arg("-C")
            .arg(&repo)
            .args(["for-each-ref", "--format=%(refname:short)", "refs/heads"])
            .output()
            .unwrap()
            .stdout,
    )
    .unwrap();
    assert!(branches.contains("feat/dirty"), "{branches}");
}

/// A worktree whose directory vanished must be pruned, not misread as holding
/// unsaved work — otherwise the registration is stranded and, because paths
/// are deterministic, that branch can never be spawned again (#56 review).
#[test]
fn remove_prunes_a_worktree_whose_directory_vanished() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let mgr = WorktreeManager::new(None);
    let path = mgr.add_new(&repo, "feat/gone").expect("add");
    std::fs::remove_dir_all(&path).unwrap();

    mgr.remove(&repo, &path)
        .expect("a vanished worktree prunes");
    // The registration is gone too, so the same branch can be spawned again.
    mgr.add_existing(&repo, "feat/gone")
        .expect("branch is spawnable again");
}

fn run_git(dir: &std::path::Path, args: &[&str]) {
    let out = Command::new("git")
        .arg("-C")
        .arg(dir)
        .args(args)
        .output()
        .expect("git spawn");
    assert!(
        out.status.success(),
        "git {args:?} failed: {}",
        String::from_utf8_lossy(&out.stderr)
    );
}

#[test]
fn add_fails_when_branch_already_exists() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    // pre-create the branch
    let status = Command::new("git")
        .arg("-C")
        .arg(&repo)
        .args(["branch", "feat/dup"])
        .status()
        .unwrap();
    assert!(status.success());

    let wt_root = TempDir::new().unwrap();
    let mgr = WorktreeManager::new(Some(wt_root.path().to_path_buf()));

    let err = mgr.add_new(&repo, "feat/dup").unwrap_err();
    let msg = format!("{err}");
    assert!(msg.contains("git exited"), "{msg}");
}

/// The project picker lists linked worktrees as pickable rows, so `base_repo`
/// is easily a worktree rather than the main checkout. Placing inside it would
/// nest one worktree in another — and git hides a registered worktree's
/// contents from the outer `git status`, so the outer tree reads clean and
/// removing it deletes the inner one's uncommitted work (#54 review).
#[test]
fn placement_resolves_a_linked_worktree_to_the_main_checkout() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let mgr = WorktreeManager::new(None);
    let outer = mgr.add_new(&repo, "feat/outer").expect("add outer");

    // Spawn again with the *worktree* as the base, the way the picker would.
    let inner = mgr.add_new(&outer, "feat/inner").expect("add inner");
    assert!(
        !inner.starts_with(&outer),
        "must not nest: {inner:?} inside {outer:?}"
    );
    assert!(
        inner.starts_with(repo.canonicalize().unwrap().join("worktrees")),
        "placed against the main checkout: {inner:?}"
    );
}

/// Belt and braces for a nesting that predates this daemon: refuse to remove
/// a worktree that has another registered underneath it.
#[test]
fn remove_refuses_a_worktree_holding_a_nested_one() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let mgr = WorktreeManager::new(None);
    let outer = mgr.add_new(&repo, "feat/outer").expect("add outer");
    // Register one by hand inside `outer`, bypassing our placement.
    let nested = outer.join("worktrees").join("hand-rolled");
    run_git(
        &repo,
        &[
            "worktree",
            "add",
            "-b",
            "feat/hand",
            nested.to_str().unwrap(),
        ],
    );
    std::fs::write(nested.join("notes.txt"), b"unsaved\n").unwrap();

    mgr.remove(&repo, &outer)
        .expect_err("a worktree holding a nested one must be refused");
    assert!(nested.join("notes.txt").exists(), "inner work survives");
}

/// Two repos spawning the same branch name under one override root must not
/// collide (#54 review).
#[test]
fn override_root_keeps_repos_apart() {
    let root_dir = TempDir::new().unwrap();
    let a_dir = TempDir::new().unwrap();
    let b_dir = TempDir::new().unwrap();
    init_repo(a_dir.path());
    init_repo(b_dir.path());

    let mgr = WorktreeManager::new(Some(root_dir.path().to_path_buf()));
    let a = mgr.add_new(a_dir.path(), "feat/shared").expect("repo a");
    let b = mgr.add_new(b_dir.path(), "feat/shared").expect("repo b");
    assert_ne!(a, b, "same branch name in two repos must not collide");
}

/// Flattening `/` and `.` to `-` made these three share one directory, and a
/// deterministic path plus a hard `PathExists` meant the losers could never
/// get a worktree (#54 review).
#[test]
fn similar_branch_names_get_distinct_directories() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let mgr = WorktreeManager::new(None);
    let a = mgr.add_new(&repo, "feat/x").expect("feat/x");
    let b = mgr.add_new(&repo, "feat.x").expect("feat.x");
    let c = mgr.add_new(&repo, "feat-x").expect("feat-x");
    assert_ne!(a, b);
    assert_ne!(b, c);
    assert_ne!(a, c);
    assert!(a.ends_with("feat/x"), "{a:?}");
}

/// The dead end the cleanup guard created: it refuses to delete unsaved work,
/// the path is deterministic, and `PathExists` is a hard error — so one stray
/// untracked file used to burn that branch permanently, with no way to clear
/// it from the product. The leftover is adopted instead (#67 review).
#[test]
fn a_guarded_leftover_is_adopted_rather_than_burning_the_branch() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    let mgr = WorktreeManager::new(None);
    let first = mgr.add_new(&repo, "feat/resume").expect("add");
    std::fs::write(first.join("notes.txt"), b"unsaved\n").unwrap();

    // The guard refuses, leaving it on disk.
    mgr.remove(&repo, &first)
        .expect_err("dirty tree is guarded");
    assert!(first.exists());

    // Spawning that branch again lands in the operator's own work, not an error.
    let again = mgr
        .add_existing(&repo, "feat/resume")
        .expect("leftover is adopted");
    assert_eq!(again, first);
    assert!(
        again.join("notes.txt").exists(),
        "their work is still there"
    );
}

/// Adoption must not extend to a directory that merely sits in the way.
#[test]
fn an_unrelated_directory_at_the_target_path_is_still_an_error() {
    let repo_dir = TempDir::new().unwrap();
    let repo = repo_dir.path().to_path_buf();
    init_repo(&repo);

    std::fs::create_dir_all(repo.join("worktrees").join("feat").join("squatter")).unwrap();
    let mgr = WorktreeManager::new(None);
    mgr.add_new(&repo, "feat/squatter")
        .expect_err("a non-worktree directory must not be adopted");
}