module log

fn log_mutable_statements(mut l Log) {
    println(@FN + ' start')
    l.info('info')
    l.warn('warn')
    l.error('error')
    l.debug('no output for debug')
    l.set_level(.debug)
    l.debug('debug now')
    l.set_level(level_from_tag('INFO') or { Level.disabled })
    l.info('info again')
    l.set_level(level_from_tag('') or { Level.disabled })
    l.error('no output anymore')
    println(@FN + ' end')
}

fn logger_mutable_statements(mut l Logger) {
    println(@FN + ' start')
    // the given logger instance could have a level to filter some levels used here
    l.info('info')
    l.warn('warn')
    l.error('error')
    l.debug('no output for debug')
    l.set_level(.debug) // change logging level, now part of the Logger interface
    l.debug('output for debug now')
    l.info('output for info now')
    println(@FN + ' end')
}

// Note that Log and Logger methods requires a mutable instance

// new_log create and return a new Log reference
pub fn new_log() &Log {
    return &Log{
        level: .info
    } // reference needed for its parallel usage
}

// new_log_as_logger create and return a new Log reference as a generic Logger
pub fn new_log_as_logger() &Logger {
    return &Log{
        level: .info
    } // reference needed for its parallel usage
}

fn test_log_mutable() {
    println(@FN + ' start')
    mut l := Log{}
    l.set_level(.info)
    log_mutable_statements(mut l)
    assert true
    println(@FN + ' end')
}

fn test_log_mutable_reference() {
    println(@FN + ' start')
    mut l := new_log()
    assert typeof(l).name == '&log.Log'
    t := spawn log_mutable_statements(mut l)
    t.wait()
    assert true
    println(@FN + ' end')
}

fn test_logger_mutable_reference() {
    println(@FN + ' start')
    // get log as Logger and use it
    mut logger := new_log_as_logger()
    logger.set_level(.warn)
    assert typeof(logger).name == '&log.Logger'
    t := spawn logger_mutable_statements(mut logger)
    t.wait()
    assert true
    println(@FN + ' end')
}

fn test_log_mutable_short_tag() {
    println(@FN + ' start')
    mut l := Log{}
    l.set_level(.info)
    l.set_short_tag(true)
    log_mutable_statements(mut l)
    assert true
    println(@FN + ' end')
}

fn test_level_from_tag() ? {
    assert level_from_tag('INFO')? == .info
    assert level_from_tag('FATAL')? == .fatal
    assert level_from_tag('WARN')? == .warn
    assert level_from_tag('ERROR')? == .error
    assert level_from_tag('DEBUG')? == .debug
    assert level_from_tag('I')? == .info
    assert level_from_tag('F')? == .fatal
    assert level_from_tag('W')? == .warn
    assert level_from_tag('E')? == .error
    assert level_from_tag('D')? == .debug

    invalid := ['', 'FOO', 'nope']

    for value in invalid {
        mut passed := false
        level_from_tag(value) or { passed = true }
        assert passed
    }
}

fn test_target_from_label() ? {
    assert target_from_label('console')? == .console
    assert target_from_label('file')? == .file
    assert target_from_label('both')? == .both

    invalid := ['', 'FOO', 'nope']

    for value in invalid {
        mut passed := false
        target_from_label(value) or { passed = true }
        assert passed
    }
}

fn test_log_time_format() {
    println(@FN + ' start')
    mut l := Log{}
    l.set_level(.info)
    l.set_time_format(.tf_rfc3339_nano)
    assert TimeFormat.tf_rfc3339_nano == l.get_time_format()
    l.info('${@FN} rfc3339_nano == YYYY-MM-DDTHH:mm:ss.123456789Z')
    l.set_time_format(.tf_ymmdd)
    assert TimeFormat.tf_ymmdd == l.get_time_format()
    l.info('${@FN} ymmdd == YYYY-MM-DD')
    l.set_custom_time_format('MMMM Do YY N kk:mm:ss A')
    assert TimeFormat.tf_custom_format == l.get_time_format()
    l.info('${@FN} custom like January 1st 22 AD 13:45:33 PM')
    assert true
    l.set_time_format(.tf_default)
    l.set_local_time(true)
    l.info('${@FN} time log in local time')
    assert l.get_local_time()
    l.set_local_time(false)
    l.info('${@FN} time log in utc time')
    assert !l.get_local_time()
    println(@FN + ' end')
}

fn make_error() ?string {
    return 'ok'
}

fn test_log_default_fatal_has_noreturn() {
    _ := make_error() or { fatal('error') }
}