class ObjectiveCLexer(RegexLexer):
    """
    For Objective-C source code with preprocessor directives.
    """
    # it would be better if this could inherit from CLexer since
    # Objective-C is a pure superset of C
    name = 'Objective-C'
    aliases = ['objective-c', 'objectivec', 'obj-c', 'objc']
    filenames = ['*.m', '*.h']
    mimetypes = []
    #: optional Comment or Whitespace
    _ws = r'(?:\s|//.*?\n|/[*].*?[*]/)+'
    tokens = {
        'whitespace': [
            (r'^\s*#if\s+0', Comment.Preproc, 'if0'),
            (r'^\s*#', Comment.Preproc, 'macro'),
            (r'\n', Text),
            (r'\s+', Text),
            (r'\\\n', Text), # line continuation
            (r'//(\n|(.|\n)*?[^\\]\n)', Comment),
            (r'/(\\\n)?[*](.|\n)*?[*](\\\n)?/', Comment),
        ],
        'statements': [
            (r'(L|@)?"', String, 'string'),
            (r"(L|@)?'(\\.|\\[0-7]{1,3}|\\x[a-fA-F0-9]{1,2}|[^\\\'\n])'", String.Char),
            (r'(\d+\.\d*|\.\d+|\d+)[eE][+-]?\d+[lL]?', Number.Float),
            (r'(\d+\.\d*|\.\d+|\d+[fF])[fF]?', Number.Float),
            (r'0x[0-9a-fA-F]+[Ll]?', Number.Hex),
            (r'0[0-7]+[Ll]?', Number.Oct),
            (r'\d+[Ll]?', Number.Integer),
            (r'[~!%^&*+=|?:<>/-]', Operator),
            (r'[()\[\],.]', Punctuation),
            (r'(auto|break|case|const|continue|default|do|else|enum|extern|'
             r'for|goto|if|register|restricted|return|sizeof|static|struct|'
             r'switch|typedef|union|volatile|virtual|while|@selector|'
             r'@private|@protected|@public|@encode|'
             r'@synchronized|@try|@throw|@catch|@finally|@end)\b', Keyword),
            (r'(int|long|float|short|double|char|unsigned|signed|void|'
             r'id|BOOL|IBOutlet|IBAction|SEL)\b', Keyword.Type),
            (r'(_{0,2}inline|naked|restrict|thread|typename)\b', Keyword.Reserved),
            (r'__(asm|int8|based|except|int16|stdcall|cdecl|fastcall|int32|'
             r'declspec|finally|int64|try|leave)\b', Keyword.Reserved),
            (r'(TRUE|FALSE|nil|NULL)\b', Name.Builtin),
            ('[a-zA-Z_][a-zA-Z0-9_]*:(?!:)', Name.Label),
            ('[a-zA-Z_][a-zA-Z0-9_]*', Name),
        ],
        'root': [
            include('whitespace'),
            # functions
            (r'((?:[a-zA-Z0-9_*\s])+?(?:\s|[*]))'    # return arguments
             r'([a-zA-Z_][a-zA-Z0-9_]*)'             # method name
             r'(\s*\([^;]*?\))'                      # signature
             r'(' + _ws + r')({)',
             bygroups(using(this), Name.Function, using(this), Text, Punctuation),
             'function'),
            # function declarations
            (r'((?:[a-zA-Z0-9_*\s])+?(?:\s|[*]))'    # return arguments
             r'([a-zA-Z_][a-zA-Z0-9_]*)'             # method name
             r'(\s*\([^;]*?\))'                      # signature
             r'(' + _ws + r')(;)',
             bygroups(using(this), Name.Function, using(this), Text, Punctuation)),           
            (r'(@interface|@implementation)(\s+)', bygroups(Keyword, Text), 'classname'),
            (r'(@class|@protocol)(\s+)', bygroups(Keyword, Text), 'forward_classname'),
            (r'(\s*)(@end)(\s*)', bygroups(Text, Keyword, Text)),
            ('', Text, 'statement'),
        ],
        'classname' : [
            # interface definition that inherits
            ('([a-zA-Z_][a-zA-Z0-9_]*)(\s*:\s*)([a-zA-Z_][a-zA-Z0-9_]*)?', bygroups(Name.Class, Text, Name.Class), '#pop'),
            # interface definition for a category
            ('([a-zA-Z_][a-zA-Z0-9_]*)(\s*)(\([a-zA-Z_][a-zA-Z0-9_]\)*)', bygroups(Name.Class, Text, Name.Label), '#pop'),
            # simple interface / implementation
            ('([a-zA-Z_][a-zA-Z0-9_]*)', Name.Class, '#pop')
        ],
        'forward_classname' : [
          ('([a-zA-Z_][a-zA-Z0-9_]*)(\s*,\s*)', bygroups(Name.Class, Text), 'forward_classname'),
          ('([a-zA-Z_][a-zA-Z0-9_]*)(\s*;?)', bygroups(Name.Class, Text), '#pop')
        ],
        'statement' : [
            include('whitespace'),
            include('statements'),
            ('[{}]', Punctuation),
            (';', Punctuation, '#pop'),
        ],
        'function': [
            include('whitespace'),
            include('statements'),
            (';', Punctuation),
            ('{', Punctuation, '#push'),
            ('}', Punctuation, '#pop'),
        ],
        'string': [
            (r'"', String, '#pop'),
            (r'\\([\\abfnrtv"\']|x[a-fA-F0-9]{2,4}|[0-7]{1,3})', String.Escape),
            (r'[^\\"\n]+', String), # all other characters
            (r'\\\n', String), # line continuation
            (r'\\', String), # stray backslash
        ],
        'macro': [
            (r'[^/\n]+', Comment.Preproc),
            (r'/[*](.|\n)*?[*]/', Comment),
            (r'//.*?\n', Comment, '#pop'),
            (r'/', Comment.Preproc),
            (r'(?<=\\)\n', Comment.Preproc),
            (r'\n', Comment.Preproc, '#pop'),
        ],
        'if0': [
            (r'^\s*#if.*?(?<!\\)\n', Comment, '#push'),
            (r'^\s*#endif.*?(?<!\\)\n', Comment, '#pop'),
            (r'.*?\n', Comment),
        ]
    }