//! Integration tests for `nbd`.
//!
//! Tests full command flows (create → read → list → update) against a real
//! temporary directory and verifies that directory traversal correctly locates
//! `.nbd/` when the binary is run from a nested subdirectory.

use std::fs;
use std::path::{Path, PathBuf};
use tempfile::TempDir;

// ── Test environment helper ───────────────────────────────────────────────────

/// A temporary project environment with `.nbd/tickets/` already initialised.
struct TestEnv {
    /// Keep `TempDir` alive — dropping it would delete the directory.
    _tmp: TempDir,
    /// The project root (the directory that contains `.nbd/`).
    pub root: PathBuf,
}

impl TestEnv {
    /// Create a fresh temporary environment with `.nbd/tickets/` ready.
    fn new() -> Self {
        let tmp = tempfile::tempdir().expect("failed to create tempdir");
        let root = tmp.path().to_path_buf();
        fs::create_dir_all(root.join(".nbd").join("tickets"))
            .expect("failed to create .nbd/tickets/");
        TestEnv { _tmp: tmp, root }
    }

    /// Spawn `nbd` with `args`, using `dir` as the working directory.
    fn run_from(&self, dir: &Path, args: &[&str]) -> std::process::Output {
        std::process::Command::new(env!("CARGO_BIN_EXE_nbd"))
            .args(args)
            .current_dir(dir)
            .output()
            .expect("failed to spawn nbd")
    }

    /// Spawn `nbd` with `args` from the project root.
    fn run(&self, args: &[&str]) -> std::process::Output {
        self.run_from(&self.root, args)
    }

    /// Run `nbd create` with the given extra arguments and return the printed
    /// ticket ID extracted from stdout.
    fn create(&self, extra_args: &[&str]) -> String {
        let mut args = vec!["create"];
        args.extend_from_slice(extra_args);
        let output = self.run(&args);
        assert!(
            output.status.success(),
            "create failed: {}",
            String::from_utf8_lossy(&output.stderr)
        );
        let stdout = String::from_utf8(output.stdout).unwrap();
        stdout
            .lines()
            .find(|l| l.trim_start().starts_with("ID:"))
            .and_then(|l| l.split_whitespace().last())
            .expect("could not extract ID from create output")
            .to_string()
    }
}

// ── Tests ─────────────────────────────────────────────────────────────────────

/// `create` then `read` produces a ticket with the expected field values.
#[test]
fn create_and_read_roundtrip() {
    let env = TestEnv::new();

    let id = env.create(&[
        "--title",
        "Fix login bug",
        "--body",
        "Users cannot log in with email addresses containing +",
        "--priority",
        "8",
        "--type",
        "bug",
    ]);

    let read = env.run(&["read", &id]);
    assert!(
        read.status.success(),
        "read failed: {}",
        String::from_utf8_lossy(&read.stderr)
    );
    let stdout = String::from_utf8(read.stdout).unwrap();
    assert!(stdout.contains(&id), "output should contain the ID");
    assert!(
        stdout.contains("Fix login bug"),
        "output should contain the title"
    );
    assert!(
        stdout.contains("Users cannot log in"),
        "output should contain the body"
    );
    assert!(stdout.contains('8'), "output should contain the priority");
    assert!(stdout.contains("bug"), "output should contain the type");
}

/// `list` displays all previously created tickets.
#[test]
fn list_shows_created_tickets() {
    let env = TestEnv::new();

    env.create(&["--title", "First ticket"]);
    env.create(&["--title", "Second ticket"]);

    let list = env.run(&["list"]);
    assert!(list.status.success());
    let stdout = String::from_utf8(list.stdout).unwrap();
    assert!(
        stdout.contains("First ticket"),
        "list should contain first ticket"
    );
    assert!(
        stdout.contains("Second ticket"),
        "list should contain second ticket"
    );
}

/// `update` changes only the specified fields; others are preserved.
#[test]
fn update_merges_correctly() {
    let env = TestEnv::new();

    let id = env.create(&[
        "--title",
        "Original title",
        "--priority",
        "5",
        "--type",
        "task",
    ]);

    // Update only the status; title and priority should be unchanged.
    let update = env.run(&["update", &id, "--status", "in_progress"]);
    assert!(
        update.status.success(),
        "update failed: {}",
        String::from_utf8_lossy(&update.stderr)
    );

    let read = env.run(&["read", &id]);
    let stdout = String::from_utf8(read.stdout).unwrap();
    assert!(
        stdout.contains("in_progress"),
        "status should be updated to in_progress"
    );
    assert!(
        stdout.contains("Original title"),
        "title should be unchanged"
    );
    assert!(stdout.contains('5'), "priority should be unchanged");
}

/// `read` works when executed from a nested subdirectory (traversal test).
#[test]
fn traversal_from_subdir() {
    let env = TestEnv::new();

    let id = env.create(&["--title", "Traversal test"]);

    // Create a nested subdirectory two levels deep.
    let subdir = env.root.join("sub").join("dir");
    fs::create_dir_all(&subdir).unwrap();

    let read = env.run_from(&subdir, &["read", &id]);
    assert!(
        read.status.success(),
        "traversal failed: {}",
        String::from_utf8_lossy(&read.stderr)
    );
    let stdout = String::from_utf8(read.stdout).unwrap();
    assert!(
        stdout.contains("Traversal test"),
        "output should contain the title"
    );
}

/// `read` with an unknown ID exits non-zero and mentions the ID in stderr.
#[test]
fn error_on_unknown_id() {
    let env = TestEnv::new();

    let result = env.run(&["read", "ffffff"]);
    assert!(
        !result.status.success(),
        "reading an unknown ID should exit non-zero"
    );
    let stderr = String::from_utf8(result.stderr).unwrap();
    assert!(
        stderr.contains("ffffff"),
        "error message should mention the ticket ID, got: {stderr}"
    );
}

/// `create --json` outputs valid JSON containing the correct field values.
#[test]
fn create_with_json_flag() {
    let env = TestEnv::new();

    let output = env.run(&[
        "create",
        "--title",
        "JSON test",
        "--priority",
        "7",
        "--json",
    ]);
    assert!(output.status.success());

    let stdout = String::from_utf8(output.stdout).unwrap();
    let parsed: serde_json::Value =
        serde_json::from_str(&stdout).expect("--json output should be valid JSON");
    assert_eq!(parsed["title"], "JSON test");
    assert_eq!(parsed["priority"], 7);
}

/// `list --json` outputs a valid JSON array with one object per ticket.
#[test]
fn list_with_json_flag() {
    let env = TestEnv::new();

    env.create(&["--title", "First"]);
    env.create(&["--title", "Second"]);

    let output = env.run(&["list", "--json"]);
    assert!(output.status.success());

    let stdout = String::from_utf8(output.stdout).unwrap();
    let parsed: serde_json::Value =
        serde_json::from_str(&stdout).expect("--json list output should be valid JSON");
    assert!(parsed.is_array(), "output should be a JSON array");
    assert_eq!(
        parsed.as_array().unwrap().len(),
        2,
        "array should contain exactly two tickets"
    );
}

/// `update --deps` replaces the dependency list.
#[test]
fn update_deps_replaces_list() {
    let env = TestEnv::new();

    // Create two tickets to use as deps.
    let dep1 = env.create(&["--title", "Dep one"]);
    let dep2 = env.create(&["--title", "Dep two"]);
    let main_id = env.create(&["--title", "Main ticket"]);

    // Add dep1 as a dependency.
    let update = env.run(&["update", &main_id, "--deps", &dep1]);
    assert!(
        update.status.success(),
        "update with deps failed: {}",
        String::from_utf8_lossy(&update.stderr)
    );

    // Replace with dep2.
    let update2 = env.run(&["update", &main_id, "--deps", &dep2]);
    assert!(update2.status.success());

    let read = env.run(&["read", &main_id, "--json"]);
    let stdout = String::from_utf8(read.stdout).unwrap();
    let parsed: serde_json::Value = serde_json::from_str(&stdout).unwrap();
    let deps = parsed["dependencies"].as_array().unwrap();
    assert_eq!(deps.len(), 1, "should have exactly one dependency");
    assert_eq!(deps[0], dep2, "dependency should be dep2");
}