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

  extras: $ => [/\s+/, $.comment],

  word: $ => $.identifier,

  conflicts: $ => [],

  rules: {
    source_file: $ => repeat($._top_statement),

    comment: $ => token(seq('//', /[^\n]*/)),

    _top_statement: $ => choice(
      $.include,
      $.toolchains,
      $.build_defaults,
      $.structured_build,
      $.legacy_build_platform,
      $.legacy_build,
      $.binary_decl,
      $.sources_decl,
      $.bool_decl,
      $.timeout_decl,
      $.memory_limit_decl,
      $.group,
    ),

    include: $ => seq(
      'include',
      field('path', $.string)
    ),

    legacy_build: $ => prec(1, seq(
      'build',
      field('command', $.string)
    )),

    legacy_build_platform: $ => seq(
      field('keyword', choice('build_linux', 'build_windows', 'build_darwin')),
      field('command', $.string)
    ),

    structured_build: $ => prec(2, seq(
      'build',
      field('name', $.string),
      field('body', $.build_block)
    )),

    build_defaults: $ => seq(
      'build_defaults',
      field('body', $.build_block)
    ),

    build_block: $ => seq(
      '{',
      repeat($._build_field),
      '}'
    ),

    _build_field: $ => choice(
      $.build_scalar_field,
      $.build_list_field,
      $.build_profile_field,
      $.build_warnings_field,
      $.define_field,
      $.os_override,
    ),

    build_scalar_field: $ => seq(
      field('name', choice('language', 'standard', 'output', 'wrapper')),
      '=',
      field('value', $.string)
    ),

    build_list_field: $ => seq(
      field('name', choice('sources', 'includes', 'sanitize', 'link', 'extra', 'platforms', 'compilers')),
      '=',
      field('value', repeat1($.string))
    ),

    build_profile_field: $ => seq(
      'profile',
      '=',
      field('value', $.profile_value)
    ),
    profile_value: $ => choice('release', 'debug', 'sanitized'),

    build_warnings_field: $ => seq(
      'warnings',
      '=',
      field('value', $.warnings_value)
    ),
    warnings_value: $ => choice('default', 'strict', 'pedantic'),

    define_field: $ => seq(
      'define',
      '(',
      field('key', $.string),
      ')',
      '=',
      field('value', $.string)
    ),

    os_override: $ => seq(
      field('os', $.os_name),
      field('body', $.build_block)
    ),
    os_name: $ => choice('linux', 'windows', 'darwin'),

    toolchains: $ => seq(
      'toolchains',
      '{',
      repeat($.toolchain_entry),
      '}'
    ),

    toolchain_entry: $ => seq(
      field('name', choice($.identifier, $.string)),
      '{',
      repeat($._toolchain_field),
      '}'
    ),

    _toolchain_field: $ => choice(
      $.toolchain_platforms_field,
      $.toolchain_binary_field,
      $.toolchain_class_field,
    ),

    toolchain_platforms_field: $ => seq(
      'platforms',
      '=',
      field('value', repeat1($.string))
    ),
    toolchain_binary_field: $ => seq(
      'binary',
      '=',
      field('value', $.string)
    ),
    toolchain_class_field: $ => seq(
      'class',
      '=',
      field('value', $.class_value)
    ),
    class_value: $ => choice('gnu', 'msvc'),

    binary_decl: $ => seq(
      'binary',
      '=',
      field('value', $.string)
    ),

    sources_decl: $ => seq(
      'sources',
      '=',
      field('value', $.string)
    ),

    bool_decl: $ => seq(
      field('name', choice('normalize_crlf', 'trim_trailing_ws')),
      '=',
      field('value', $.bool)
    ),

    timeout_decl: $ => seq(
      'timeout',
      field('value', $.duration)
    ),

    memory_limit_decl: $ => seq(
      'memory_limit',
      '=',
      field('value', $.size)
    ),

    group: $ => seq(
      'group',
      '(',
      field('name', $.string),
      ')',
      '{',
      repeat($._group_field),
      '}'
    ),

    _group_field: $ => choice(
      $.group_weight_field,
      $.group_timeout_field,
      $.group_memory_field,
      $.group_scoring_field,
      $.group_wrapper_field,
      $.env_decl,
      $.test,
      $.pattern,
    ),

    group_weight_field: $ => seq('weight', '=', field('value', $.number)),
    group_timeout_field: $ => seq('timeout', '=', field('value', $.duration)),
    group_memory_field: $ => seq('memory_limit', '=', field('value', $.size)),
    group_scoring_field: $ => seq('scoring', '=', field('value', $.scoring_value)),
    scoring_value: $ => choice('partial', 'all_or_none'),
    group_wrapper_field: $ => seq('wrapper', '=', field('value', $.string)),

    env_decl: $ => seq(
      'env',
      '(',
      field('key', $.string),
      ')',
      '=',
      field('value', $.string)
    ),

    test: $ => seq(
      'test',
      '(',
      field('name', $.string),
      ')',
      '{',
      repeat($._test_field),
      '}'
    ),

    _test_field: $ => choice(
      $.test_stdin_field,
      $.test_stdout_field,
      $.test_stderr_field,
      $.test_args_field,
      $.test_exit_code_field,
      $.test_timeout_field,
      $.test_memory_field,
      $.test_wrapper_field,
      $.env_decl,
      $.file_decl,
      $.out_file_decl,
    ),

    test_stdin_field: $ => seq('stdin', '=', field('value', $.string)),
    test_stdout_field: $ => seq('stdout', $._matcher),
    test_stderr_field: $ => seq('stderr', $._matcher),
    test_args_field: $ => seq('args', '=', field('value', repeat1($.string))),
    test_exit_code_field: $ => seq('exitCode', '=', field('value', $.integer)),
    test_timeout_field: $ => seq('timeout', '=', field('value', $.duration)),
    test_memory_field: $ => seq('memory_limit', '=', field('value', $.size)),
    test_wrapper_field: $ => seq('wrapper', '=', field('value', $.string)),

    file_decl: $ => seq(
      'file',
      '(',
      field('key', $.string),
      ')',
      '=',
      field('value', $.string)
    ),

    out_file_decl: $ => seq(
      'outFile',
      '(',
      field('key', $.string),
      ')',
      '=',
      field('value', $.string)
    ),

    _matcher: $ => choice(
      $.exact_matcher,
      $.numeric_matcher,
      $.contains_matcher,
      $.regex_matcher,
      $.any_order_matcher,
    ),

    exact_matcher: $ => seq('=', field('value', $.string)),
    numeric_matcher: $ => seq(
      '~',
      field('epsilon', $.number),
      'of',
      field('value', $.string)
    ),
    contains_matcher: $ => seq('contains', field('value', $.string)),
    regex_matcher: $ => seq('matches', field('pattern', $.regex_string)),
    any_order_matcher: $ => seq(
      'anyOrder',
      '{',
      repeat1($.string),
      '}'
    ),

    pattern: $ => seq(
      'pattern',
      '{',
      repeat($._pattern_field),
      '}'
    ),

    _pattern_field: $ => choice(
      $.pattern_input_field,
      $.pattern_output_field,
      $.pattern_dirs_field,
      $.pattern_args_field,
    ),

    pattern_input_field: $ => seq('input', '=', field('value', $.string)),
    pattern_output_field: $ => seq('output', '=', field('value', $.string)),
    pattern_dirs_field: $ => seq('dirs', '=', field('value', $.string)),
    pattern_args_field: $ => seq('args', '=', field('value', repeat1($.string))),

    bool: $ => choice('true', 'false'),

    number: $ => choice($.integer, $.float),

    string: $ => choice(
      $.heredoc_string,
      $.simple_string,
    ),

    simple_string: $ => token(seq(
      '"',
      repeat(choice(
        /[^"\\\n]/,
        seq('\\', /./)
      )),
      '"'
    )),

    heredoc_string: $ => token(seq(
      '"""',
      /([^"]|"[^"]|""[^"])*/,
      '"""'
    )),

    regex_string: $ => $.simple_string,

    identifier: $ => /[a-zA-Z_][a-zA-Z0-9_]*/,

    integer: $ => token(/-?\d+/),
    float: $ => token(/-?\d+\.\d+/),
    duration: $ => token(/\d+(ms|s|m)/),
    size: $ => token(/\d+(KiB|MiB|GiB|KB|MB|GB|B|K|M|G)/),
  }
});