import re

from gadict_util import ParseException

class Parser:

    """

    Parser of gadialog files of form:

        # num1

        - sentence1

        - sentence2

        # num2

        - sentence1

        ...

    converting them to map:

        obj.dom[num1] = [sentence1, sentence2, ...]

    """

    COMMENT_RE = re.compile("^; ")

    NUM_RE = re.compile(u"^# ([1-9][0-9]*)$")

    PHRASE_START_RE = re.compile(u"^- (.*)")

    def __init__(self):

        pass

    def readline(self):

        while True:

            self.line = self.stream.readline()

            self.eof = len(self.line) == 0

            if self.eof:

                break

            self.lineno += 1

            if self.COMMENT_RE.search(self.line):

                continue

            self.line = self.line.strip(' \n\t')

            if len(self.line) > 0:

                break

    def parse(self, stream):

        self.lineno = 0

        self.stream = stream

        self.dom = dict()

        self.eof = False

        try:

            self.parse_prelude()

            while not self.eof:

                self.parse_article()

        except ParseException as ex:

            if sys.version_info.major == 2:

                import traceback

                traceback.print_exc()

            raise ParseException(ex.msg, self.lineno, self.line)

        return self.dom

    def parse_prelude(self):

        while True:

            self.readline()

            if self.eof:

                return

            m = self.NUM_RE.match(self.line)

            if m:

                self.num = m.group(1)

                break

    def parse_article(self):

        """Assume we are at ``# NUM`` line."""

        num = self.num

        phrase_buf = []

        phrases = []

        while True:

            self.readline()

            if self.eof:

                if len(phrase_buf) > 0:

                    phrases.append(" ".join(phrase_buf))

                break

            m = self.NUM_RE.match(self.line)

            if m:

                if len(phrase_buf) > 0:

                    phrases.append(" ".join(phrase_buf))

                self.num = m.group(1)

                break

            m = self.PHRASE_START_RE.match(self.line)

            if m:

                if len(phrase_buf) > 0:

                    phrases.append(" ".join(phrase_buf))

                phrase_buf = [m.group(1)]

            else:

                phrase_buf.append(self.line)

        if len(phrases) == 0:

            raise ParseException("""There are no any phrases...""")

        if num in self.dom:

            raise ParseException("""Conflicting key: {}...""".format(num))

        self.dom[num] = phrases