from method import Method
import buffer.color
import util
import lex

class VcException(Exception): pass

class VcBlame(Method):
    _is_method      = False
    line_re         = None
    prefix_fmt      = None
    pretest_err_msg = None
    def _pretest(self):
        return True
    def _filter(self, line):
        m = self.line_re.match(line)
        if not m:
            raise VcException("couldn't parse %r" % line)
        return m.groupdict()
    def _open_pipe(self, w, **vargs):
        raise Exception('unimplemented')
    def _execute(self, w, **vargs):
        if not self._pretest():
            w.set_error(self.pretest_err_msg)
            return
        elif not hasattr(w.buffer, 'path'):
            w.set_error("Buffer has no corresponding file")
            return

        pipe   = self._open_pipe(w, **vargs)
        groups = [self._filter(line) for line in pipe.stdout]
        status = pipe.wait() >> 8

        if w.mode.grammar:
            lexer = lex.Lexer(w.mode, w.mode.grammar)
            tokens = list(lexer.lex([d['content'] for d in groups]))
            for t in tokens:
                groups[t.y].setdefault('tokens', [])
                groups[t.y]['tokens'].append(t)

        lines = []
        for d in groups:
            if d['tokens']:
                suffix = ''
                for t in d['tokens']:
                    code = buffer.color.get_cbuf_code(*t.color)
                    suffix += code + util.cbuf_escape(t.string)
            else:
                suffix = d['content'] + '\n'
            lines.append(self.prefix_fmt % d + ' ' + suffix)
        data = ''.join(lines)

        if status == 0:
            w.application.color_data_buffer("*Blame*", data, switch_to=True)
        else:
            w.set_error("There was an error (%s)" % (status))