use lazy_static::lazy_static;
use std::fs;
use std::path::{Path, PathBuf};
use tree_sitter::Language;
use tree_sitter_highlight::HighlightConfiguration;
use tree_sitter_loader::Loader;
use tree_sitter_tags::TagsConfiguration;

include!("./dirs.rs");

lazy_static! {
    static ref TEST_LOADER: Loader = Loader::with_parser_lib_path(SCRATCH_DIR.join("lib"));
}

pub fn test_loader<'a>() -> &'a Loader {
    &*TEST_LOADER
}

pub fn fixtures_dir<'a>() -> &'static Path {
    &FIXTURES_DIR
}

pub fn get_language(name: &str) -> Language {
    TEST_LOADER
        .load_language_at_path(&GRAMMARS_DIR.join(name).join("src"), &HEADER_DIR)
        .unwrap()
}

pub fn get_language_queries_path(language_name: &str) -> PathBuf {
    GRAMMARS_DIR.join(language_name).join("queries")
}

pub fn get_highlight_config(
    language_name: &str,
    injection_query_filename: Option<&str>,
    highlight_names: &[String],
) -> HighlightConfiguration {
    let language = get_language(language_name);
    let queries_path = get_language_queries_path(language_name);
    let highlights_query = fs::read_to_string(queries_path.join("highlights.scm")).unwrap();
    let injections_query = if let Some(injection_query_filename) = injection_query_filename {
        fs::read_to_string(queries_path.join(injection_query_filename)).unwrap()
    } else {
        String::new()
    };
    let locals_query = fs::read_to_string(queries_path.join("locals.scm")).unwrap_or(String::new());
    let mut result = HighlightConfiguration::new(
        language,
        &highlights_query,
        &injections_query,
        &locals_query,
    )
    .unwrap();
    result.configure(&highlight_names);
    result
}

pub fn get_tags_config(language_name: &str) -> TagsConfiguration {
    let language = get_language(language_name);
    let queries_path = get_language_queries_path(language_name);
    let tags_query = fs::read_to_string(queries_path.join("tags.scm")).unwrap();
    let locals_query = fs::read_to_string(queries_path.join("locals.scm")).unwrap_or(String::new());
    TagsConfiguration::new(language, &tags_query, &locals_query).unwrap()
}

pub fn get_test_language(
    name: &str,
    parser_code: &str,
    scanner_src_path: Option<&Path>,
) -> Language {
    let src_dir = SCRATCH_DIR.join("src").join(name);
    fs::create_dir_all(&src_dir).unwrap();

    let parser_path = src_dir.join("parser.c");
    if !fs::read_to_string(&parser_path).map_or(false, |content| content == parser_code) {
        fs::write(&parser_path, parser_code).unwrap();
    }

    if let Some(scanner_src_path) = scanner_src_path {
        let scanner_code = fs::read_to_string(&scanner_src_path).unwrap();
        let scanner_path = src_dir.join("scanner.c");
        if !fs::read_to_string(&scanner_path).map_or(false, |content| content == scanner_code) {
            fs::write(&scanner_path, scanner_code).unwrap();
        }
    }

    TEST_LOADER
        .load_language_at_path_with_name(&src_dir, &HEADER_DIR, name)
        .unwrap()
}