module.exports = grammar({
    name: 'Groovy',

    rules: {
        // TODO: add the actual grammar rules
        source_file: $ => seq(
            optional($._shebang_comment),
            optional(seq($.package_definition, repeat($._nl_semicolon))),
            repeat(
                choice(
                    seq(
                        $.import_statement,
                        repeat1($._nl_semicolon)
                    ),
                    seq(
                        $.script_part,
                        repeat1($._nl_semicolon)
                    )
                )
            ),
            optional($.script_part)
        ),
        import_statement: $ => seq(
            'import',
            optional('static'),
            field('name',
                seq(
                    $.identifier,
                    repeat(seq('.', $.identifier)),
                    optional(seq('.', '*')
                    )
                )
            )
        ),
        _shebang_comment: $ => token.immediate(/#!.*\n/),
        package_definition: $ => seq(
            'package',
            field('name', seq(
                $.identifier,
                repeat(seq('.', $.identifier))))
        ),
        script_part: $ => choice(
            $.statement,
            $.method_declaration
        ),
        expression: $ => choice(
            $.path_expression
        ),
        path_expression: $ => seq(
            repeat(
                seq($.identifier, '.')
            ),
            $.identifier
        ),
        identifier: $ => /[A-Za-z_][A-Za-z_0-9]*/,
        statement: $ => choice(
            $.expression
        ),
        method_declaration: $ => seq('def', field('name', $.identifier)),
        _nl_semicolon: $ => choice('\n', ';'),
        word: $ => $.identifier
    }
});