use std::fs;

use archlens::run;

fn create_rust_project(dir: &std::path::Path) {
    fs::create_dir_all(dir.join("src")).unwrap();
    fs::write(
        dir.join("src/order.rs"),
        "pub struct Order {\n    pub id: u64,\n}\n",
    )
    .unwrap();
    fs::write(
        dir.join("src/service.rs"),
        "pub struct OrderService {\n    order: Order,\n}\n",
    )
    .unwrap();
}

fn create_multi_module_project(dir: &std::path::Path) {
    fs::create_dir_all(dir.join("src/orders")).unwrap();
    fs::create_dir_all(dir.join("src/billing")).unwrap();
    fs::write(
        dir.join("src/orders/order.rs"),
        "pub struct Order {\n    pub id: u64,\n}\n",
    )
    .unwrap();
    fs::write(
        dir.join("src/orders/service.rs"),
        "pub struct OrderService {\n    order: Order,\n}\n",
    )
    .unwrap();
    fs::write(
        dir.join("src/billing/invoice.rs"),
        "pub struct Invoice {\n    pub total: f64,\n}\n",
    )
    .unwrap();
}

#[test]
fn analyzes_rust_project_and_writes_mermaid_to_file() {
    let project = tempfile::tempdir().unwrap();
    create_rust_project(project.path());

    let output_dir = tempfile::tempdir().unwrap();
    let output_file = output_dir.path().join("arch.mmd");

    run(archlens::CliArgs {
        command: None,
        path: project.path().to_path_buf(),
        level: "type".to_string(),
        format: "mermaid".to_string(),
        output: Some(output_file.to_str().unwrap().to_string()),
        config: None,
        scope: None,
        exclude: vec![],
        include_tests: false,
        no_weights: false,
        watch: false,
        since: None,
        split_by_module: false,
        strict: false,
        check: false,
        verbose: 0,
    })
    .unwrap();

    let content = fs::read_to_string(&output_file).unwrap();
    assert!(content.contains("classDiagram"));
    assert!(content.contains("Order"));
    assert!(content.contains("OrderService"));
}

#[test]
fn works_without_config_file() {
    let project = tempfile::tempdir().unwrap();
    create_rust_project(project.path());

    let output_dir = tempfile::tempdir().unwrap();
    let output_file = output_dir.path().join("arch.mmd");

    let result = run(archlens::CliArgs {
        command: None,
        path: project.path().to_path_buf(),
        level: "type".to_string(),
        format: "mermaid".to_string(),
        output: Some(output_file.to_str().unwrap().to_string()),
        config: None,
        scope: None,
        exclude: vec![],
        include_tests: false,
        no_weights: false,
        watch: false,
        since: None,
        split_by_module: false,
        strict: false,
        check: false,
        verbose: 0,
    });

    assert!(result.is_ok());
}

#[test]
fn split_by_module_writes_overview_and_per_module_files() {
    let project = tempfile::tempdir().unwrap();
    create_multi_module_project(project.path());

    let output_dir = tempfile::tempdir().unwrap();

    run(archlens::CliArgs {
        command: None,
        path: project.path().to_path_buf(),
        level: "module".to_string(),
        format: "mermaid".to_string(),
        output: Some(output_dir.path().to_str().unwrap().to_string()),
        config: None,
        scope: None,
        exclude: vec![],
        include_tests: false,
        no_weights: false,
        watch: false,
        since: None,
        split_by_module: true,
        strict: false,
        check: false,
        verbose: 0,
    })
    .unwrap();

    let overview = output_dir.path().join("overview.mmd");
    assert!(overview.exists(), "overview.mmd should exist");

    let overview_content = fs::read_to_string(&overview).unwrap();
    assert!(overview_content.contains("graph TD") || overview_content.contains("classDiagram"));

    let entries: Vec<_> = fs::read_dir(output_dir.path())
        .unwrap()
        .filter_map(|e| e.ok())
        .collect();

    assert!(
        entries.len() > 1,
        "should have overview + at least one module file"
    );
}

fn create_cross_module_project(dir: &std::path::Path) {
    fs::create_dir_all(dir.join("src/app")).unwrap();
    fs::create_dir_all(dir.join("src/domain")).unwrap();
    fs::write(
        dir.join("src/domain/order.rs"),
        "pub struct Order { pub id: u64 }\n",
    )
    .unwrap();
    fs::write(
        dir.join("src/app/service.rs"),
        "use crate::domain::Order;\npub struct OrderService { order: Order }\n",
    )
    .unwrap();
}

#[test]
fn per_module_file_shows_cross_module_dependency_arrows() {
    let project = tempfile::tempdir().unwrap();
    create_cross_module_project(project.path());

    let output_dir = tempfile::tempdir().unwrap();

    run(archlens::CliArgs {
        command: None,
        path: project.path().to_path_buf(),
        level: "type".to_string(),
        format: "mermaid".to_string(),
        output: Some(output_dir.path().to_str().unwrap().to_string()),
        config: None,
        scope: None,
        exclude: vec![],
        include_tests: false,
        no_weights: false,
        watch: false,
        since: None,
        split_by_module: true,
        strict: false,
        check: false,
        verbose: 0,
    })
    .unwrap();

    let app_file = output_dir.path().join("app.mmd");
    assert!(app_file.exists(), "app.mmd should exist");

    let content = fs::read_to_string(&app_file).unwrap();
    assert!(
        content.contains("<<module>>"),
        "per-module file should contain external module placeholder: {content}"
    );
    assert!(
        content.contains("domain"),
        "per-module file should reference the domain module: {content}"
    );
}