import commands, curses, os
import color, method, mode
from lex import Grammar, PatternRule, RegionRule
from mode.text import TextInsertSpace

class LatexGrammar(Grammar):
    rules = [
        PatternRule(r'comment', r'\%.*$'),
        PatternRule(r'latex_wrapper', r'\\(?:begin|end)'),
        PatternRule(r'latex_control', r'\\[a-zA-Z]+'),
        RegionRule(r'latex_argument', r'{', None, r'}'),
        RegionRule(r'latex_string', r"``", None, r"''"),
        RegionRule(r'latex_string', r"`", None, r"'"),
        PatternRule(r'latex_escaped', r'\\.'),
        PatternRule(r'latex_special', r'[{}$^_%~#&]'),
    ]

class Latex(mode.Fundamental):
    modename   = 'Latex'
    extensions = ['.latex', '.tex']
    grammar    = LatexGrammar
    colors     = {
        'latex_wrapper':       ('magenta', 'default', 'bold'),
        'latex_control':       ('blue', 'default', 'bold'),
        'latex_argument.null': ('cyan', 'default', 'bold'),
        'latex_string.start':  ('green', 'default', 'bold'),
        'latex_string.null':   ('green', 'default', 'bold'),
        'latex_string.end':    ('green', 'default', 'bold'),
        'latex_escaped':       ('magenta', 'default', 'bold'),
    }
    config = {
        'latex.buildcmd':    'latex',
        'latex.pdfbuildcmd': 'pdflatex',
        'latex.pdfviewcmd':  'evince',
    }

    def __init__(self, w):
        mode.Fundamental.__init__(self, w)
        self.add_bindings('wrap-paragraph', ('M-q',))
        self.add_action_and_bindings(LatexCommentRegion(), ('C-c #', "C-c \%"))
        self.add_action_and_bindings(LatexUncommentRegion(), ('C-u C-c #', "C-u C-c \%"))
        self.add_action_and_bindings(LatexInsertSquotes(), ("M-'",))
        self.add_action_and_bindings(LatexInsertDquotes(), ('M-"',))
        self.add_action_and_bindings(LatexInsertBraces(), ('M-{',))
        self.add_action_and_bindings(LatexBuild(), ("C-c C-c", 'C-c B'))
        self.add_action_and_bindings(LatexInsertSpace(), ('SPACE',))
        self.add_action_and_bindings(LatexBuildPdf(), ("C-c C-p",))
        self.add_action_and_bindings(LatexViewPdf(), ('C-c C-v',))
        self.add_action(LatexCheckSpelling())

class LatexBuild(method.Method):
    '''Insert a pair of LaTeX-style single-quotes into the buffer'''
    def _getcmd(self, w):
        return w.application.config.get('latex.buildcmd')
    def _build(self, w):
        if w.buffer.changed():
            return (True, 'Build Cancelled: unsaved buffer')
        app = w.application
        buildcmd = self._getcmd(w)
        cmd = "%s '\\batchmode\\input %s' >/dev/null 2>&1" % (buildcmd,
                                                              w.buffer.path)
        status = os.system(cmd)
        if status == 0:
            return (True, 'Build OK')
        else:
            return (False, 'Build Error')
    def _modpath(self, w, ext):
        return os.path.splitext(w.buffer.path)[0] + ext
    def _readlog(self, w):
        logpath = self._modpath(w, '.log')
        f = open(logpath, 'r')
        output = f.read()
        f.close()
        return output
    def _execute(self, w, **vargs):
        (ok, mesg) = self._build(w)
        w.set_error(mesg)
        if not ok:
            output = self._readlog(w)
            bufname = '*%s*' % self.name
            w.application.data_buffer(bufname, output, switch_to=not ok)
        return ok

class LatexBuildPdf(LatexBuild):
    '''Insert a pair of LaTeX-style single-quotes into the buffer'''
    def _getcmd(self, w):
        return w.application.config.get('latex.pdfbuildcmd')
class LatexViewPdf(LatexBuildPdf):
    '''Insert a pair of LaTeX-style single-quotes into the buffer'''
    def _execute(self, w, **vargs):
        ok = LatexBuildPdf._execute(self, w, **vargs)
        if ok:
            viewcmd = w.application.config.get('latex.pdfviewcmd')
            pid = os.fork()
            if pid == 0:
                pdfpath = self._modpath(w, '.pdf')
                os.execvp(viewcmd, (viewcmd, pdfpath))

class LatexCommentRegion(method.CommentRegion):
    commentc = '%'
class LatexUncommentRegion(method.UncommentRegion):
    commentc = '%'

class LatexInsertSquotes(method.Method):
    '''Insert a pair of LaTeX-style single-quotes into the buffer'''
    def _execute(self, w, **vargs):
        w.insert_string_at_cursor("`'")
        w.backward()
class LatexInsertDquotes(method.Method):
    '''Insert a pair of LaTeX-style double-quotes into the buffer'''
    def _execute(self, w, **vargs):
        w.insert_string_at_cursor("``''")
        w.backward()
        w.backward()
class LatexInsertBraces(method.Method):
    '''Insert a pair of curly braces into the buffer'''
    def _execute(self, w, **vargs):
        w.insert_string_at_cursor("{}")
        w.backward()

class LatexInsertSpace(TextInsertSpace):
    pass

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

install = Latex.install