import os
import term
import v.util.vtest
import v.util.diff

const vexe = @VEXE

const vroot = @VMODROOT

const github_job = os.getenv('GITHUB_JOB')

@[noreturn]
fn exit_because(msg string) {
    eprintln('${msg}, tests will not run')
    exit(0)
}

fn test_node_exists() {
    res := os.execute('node --version')
    if res.exit_code != 0 {
        exit_because('node does not exist')
    }
    if !res.output.starts_with('v') {
        exit_because('invalid node version')
    }
    version := res.output.trim_left('v').int()
    if version < 10 {
        exit_because('node should be at least version 10, but is currently version: ${version}')
    }
    println('Using node version: ${version}')
    // if github_job != '' && os.user_os() == 'macos' {
    //    exit_because('program_test.v is flaky on macos')
    //}
}

fn test_running_programs_compiled_with_the_js_backend() {
    os.setenv('VCOLORS', 'never', true)
    os.chdir(vroot) or {}
    test_dir := 'vlib/v/gen/js/tests/testdata'
    main_files := get_main_files_in_dir(test_dir)
    fails := check_path(test_dir, main_files)!
    assert fails == 0
}

fn get_main_files_in_dir(dir string) []string {
    mut mfiles := os.walk_ext(dir, '.v')
    mfiles.sort()
    return mfiles
}

fn check_path(dir string, tests []string) !int {
    mut nb_fail := 0
    paths := vtest.filter_vtest_only(tests, basepath: vroot)
    for path in paths {
        program := path.replace(vroot + os.path_separator, '')
        program_out := program.replace('.v', '.out')
        if !os.exists(program_out) {
            os.write_file(program_out, '')!
        }
        print(program + ' ')
        res := os.execute('${os.quoted_path(vexe)} -b js_node run ${os.quoted_path(program)}')
        if res.exit_code < 0 {
            panic(res.output)
        }
        mut expected := os.read_file(program_out)!
        expected = clean_line_endings(expected)
        found := clean_line_endings(res.output)
        if expected != found {
            println(term.red('FAIL'))
            println('============')
            if diff_ := diff.compare_text(expected, found) {
                println('diff:')
                println(diff_)
            } else {
                println('expected ${program_out} content:')
                println(expected)
                println('============')
                println('found:')
                println(found)
            }
            println('============\n')
            nb_fail++
        } else {
            println(term.green('OK'))
            assert true
        }
    }
    return nb_fail
}

fn clean_line_endings(s string) string {
    mut res := s.trim_space()
    res = res.replace(' \n', '\n')
    res = res.replace(' \r\n', '\n')
    res = res.replace('\r\n', '\n')
    res = res.trim('\n')
    return res
}