//! Integration tests for the `diagpick` command.

use std::fs;
use std::path::PathBuf;
use tempfile::tempdir;

use assert_cmd::Command;
use predicates::prelude::*;

fn cargo_command() -> Command {
    Command::cargo_bin("diagpick").expect("binary")
}

fn workspace_root() -> PathBuf {
    PathBuf::from(env!("CARGO_MANIFEST_DIR"))
        .join("..")
        .join("..")
        .canonicalize()
        .expect("workspace root")
}

fn fixture_relative(path: &str) -> PathBuf {
    PathBuf::from("fixtures").join(path)
}

fn fixture(path: &str) -> PathBuf {
    workspace_root().join(fixture_relative(path))
}

fn relative_to_workspace(path: &str) -> String {
    fixture_relative(path).display().to_string()
}

fn pwsh_command(script: impl AsRef<str>) -> Command {
    let mut command = Command::new("pwsh");
    command
        .arg("-NoProfile")
        .arg("-Command")
        .arg(script.as_ref());
    command
}

#[test]
fn extracts_rust_diagnostics_in_text_mode() {
    let mut command = cargo_command();
    command
        .current_dir(workspace_root())
        .arg(fixture("diag/rust-errors.txt"))
        .assert()
        .success()
        .stdout(predicate::str::contains("severity=error code=E0425"))
        .stdout(predicate::str::contains("sample.rs line=25 column=11"))
        .stdout(predicate::str::contains("severity=warning code=-"))
        .stdout(predicate::str::contains("sample.rs line=33 column=4"));
}

#[test]
fn filters_unity_diagnostics_and_attaches_source_as_json() {
    let mut command = cargo_command();
    command
        .current_dir(workspace_root())
        .arg("--json")
        .arg("--severity")
        .arg("error")
        .arg("--with-source")
        .arg("--context")
        .arg("1")
        .arg(fixture("diag/unity-errors.txt"))
        .assert()
        .success()
        .stdout(predicate::str::contains("\"severity\":\"error\""))
        .stdout(predicate::str::contains("\"code\":\"CS0103\""))
        .stdout(predicate::str::contains("\"path\":\""))
        .stdout(predicate::str::contains("sample.cs"))
        .stdout(predicate::str::contains("\"start_line\":8"))
        .stdout(predicate::str::contains("ComputeScore"))
        .stdout(predicate::str::contains("CS0168").not());
}

#[test]
fn supports_powershell_pipeline_input() {
    let binary = assert_cmd::cargo::cargo_bin("diagpick");
    let input = relative_to_workspace("diag/unity-errors.txt");
    let script = format!(
        "[System.IO.File]::ReadLines('{}') | & '{}' --json",
        input,
        binary.display()
    );

    let mut command = pwsh_command(script);
    command
        .current_dir(workspace_root())
        .assert()
        .success()
        .stdout(predicate::str::contains("\"code\":\"CS0103\""))
        .stdout(predicate::str::contains("\"severity\":\"warning\""));
}

#[test]
fn utf8_bom_stdin_still_extracts_first_diagnostic() {
    let mut command = cargo_command();
    command
        .write_stdin(
            "\u{feff}error[E0425]: cannot find value `missing` in this scope\n  --> sample.rs:25:11\n",
        )
        .assert()
        .success()
        .stdout(predicate::str::contains("severity=error code=E0425"))
        .stdout(predicate::str::contains("sample.rs line=25 column=11"));
}

#[test]
fn utf8_bom_log_file_still_extracts_diagnostics() {
    let dir = tempdir().expect("tempdir");
    let log_path = dir.path().join("bom-rust-errors.txt");
    let mut bytes = vec![0xEF, 0xBB, 0xBF];
    bytes.extend(fs::read(fixture("diag/rust-errors.txt")).expect("fixture"));
    fs::write(&log_path, bytes).expect("log fixture");

    let mut command = cargo_command();
    command
        .current_dir(workspace_root())
        .arg(&log_path)
        .assert()
        .success()
        .stdout(predicate::str::contains("severity=error code=E0425"))
        .stdout(predicate::str::contains("sample.rs line=25 column=11"));
}

#[test]
fn invalid_utf8_log_file_reports_read_error() {
    let dir = tempdir().expect("tempdir");
    let log_path = dir.path().join("invalid-utf8.log");
    fs::write(&log_path, [0x66, 0x6F, 0x80, 0x6F]).expect("log fixture");

    let mut command = cargo_command();
    command
        .current_dir(workspace_root())
        .arg(&log_path)
        .assert()
        .failure()
        .stderr(predicate::str::contains("failed to read"))
        .stderr(predicate::str::contains("invalid-utf8.log"));
}

#[test]
fn help_includes_diagnostic_examples() {
    let mut command = cargo_command();
    command
        .arg("--help")
        .assert()
        .success()
        .stdout(predicate::str::contains("--with-source"))
        .stdout(predicate::str::contains("ConvertFrom-Json"))
        .stdout(predicate::str::contains(
            "diagpick .\\fixtures\\diag\\rust-errors.txt",
        ));
}

#[test]
fn emits_tool_fallback_for_actionable_cargo_errors() {
    let temp = tempdir().expect("tempdir");
    let log = temp.path().join("cargo.log");
    fs::write(
        &log,
        "error: package ID specification `missing-crate` did not match any packages\n",
    )
    .expect("fixture");

    let mut command = cargo_command();
    command
        .arg("--json")
        .arg(&log)
        .assert()
        .success()
        .stdout(predicate::str::contains("\"tool_hint\":\"cargo\""))
        .stdout(predicate::str::contains("\"path\":\"<cargo>\""));
}