import os
import color, method, mode
from lex import Grammar, PatternRule, RegionRule
from mode.xml import TagGrammar
from mode.javascript import JavascriptGrammar
from mode.css import CSSGrammar

class HTMLGrammar(Grammar):
    rules = [
        # TODO: how does cdata work again?
        RegionRule(r'comment', r'<!--', Grammar, r'-->'),
        # BUG: not all scripts are javascript and not all styles are CSS
        # but, dynamically choosing a grammar based on the 'type' attribute
        # (which may be on a different line) is impractical.
        RegionRule(r'script', r'<(?=script[^a-zA-Z0-9_])', TagGrammar, r'>', JavascriptGrammar, r'</(?=script>)', TagGrammar, r'>'),
        RegionRule(r'style', r'<(?=style[^a-zA-Z0-9_])', TagGrammar, r'>', CSSGrammar, r'</(?=style>)', TagGrammar, r'>'),
        RegionRule(r'tag', r'</?', TagGrammar, r'/?>'),
    ]

class HtmlViewPage(method.Method):
    '''View the HTML data in a browser (curses or external)'''
    def _execute(self, w, **vargs):
        viewcmd = w.application.config.get('html.viewcmd')
        viewbg  = viewcmd.endswith('&')
        if viewbg:
            viewcmd = viewcmd[:-1]
        argv = (viewcmd, w.buffer.path)
        if viewbg:
            if os.fork() == 0:
                try:
                    os.execvp(viewcmd, argv)
                except OSError:
                    os._exit(1)
        else:
            w.application.run_external(*argv)

class HtmlCheckSpelling(method.Method):
    """Check the spelling of the document via ispell -t"""
    def _execute(self, w, **vargs):
        # -x   no backup file
        # -M   show context menu
        # -H   treat input document as HTML
        w.application.run_external('ispell', '-x', '-M', '-H', w.buffer.path)
        if w.buffer.changed_on_disk():
            w.buffer.reload()

class HTML(mode.Fundamental):
    modename   = 'HTML'
    extensions = ['.html', '.htm', '.shtml', '.shtm', '.xhtml']
    grammar    = HTMLGrammar
    colors     = {}
    config     = {
        'html.viewcmd': 'firefox&',
    }

    _colorbase = {
        'start':        ('default', 'default'),
        'namespace':    ('magenta', 'default'),
        'name':         ('blue', 'default'),
        'attrname':     ('cyan', 'default'),
        'string.start': ('green', 'default'),
        'string.null':  ('green', 'default'),
        'string.end':   ('green', 'default'),
        'end':          ('default', 'default'),
    }
    for _name in _colorbase:
        colors['script.%s' % _name] = _colorbase[_name]
        colors['style.%s' % _name]  = _colorbase[_name]
        colors['tag.%s' % _name]    = _colorbase[_name]

    def __init__(self, w):
        mode.Fundamental.__init__(self, w)
        self.add_bindings('close-paren', (')',))
        self.add_bindings('close-brace', ('}',))
        self.add_bindings('close-bracket', (']',))
        self.add_action(HtmlViewPage())
        self.add_action(HtmlCheckSpelling())

install = HTML.install