# domato canvas generator.py replacement, put meta refresh tag at top of template.html
# author: stelios

from __future__ import print_function
import os
import re
import random
import sys
import cherrypy
import time

parent_dir = os.path.abspath(os.path.join(os.path.dirname(__file__), os.pardir))
sys.path.append(parent_dir)
from grammar import Grammar

_N_MAIN_LINES = 1000
_N_EVENTHANDLER_LINES = 500



class DomFuzzer(object):
    def index(self):
        outfile = 'out/%d.html' % time.time()
        result = self.GenerateNewSample()

        if result is not None:
            print('Writing a sample to ' + outfile)
            try:
                f = open(outfile, 'w')
                f.write(result)
                f.close()
            except IOError:
                print('Error writing to output')

        return result
    index.exposed = True

    def __init__(self, grammar_dir):
        self.template = None
        self.jsgrammar = None

        f = open(os.path.join(grammar_dir, 'template.html'))
        self.template = f.read()
        f.close()

        self.jsgrammar = Grammar()
        err = self.jsgrammar.parse_from_file(os.path.join(grammar_dir, 'canvas.txt'))
        if err > 0:
            print('There were errors parsing grammar')
            return

    def generate_function_body(self, num_lines):
        js = ''
        js += self.jsgrammar._generate_code(num_lines)

        return js

    def GenerateNewSample(self):
        """Parses grammar rules from string.

        Args:
          template: A template string.
          htmlgrammar: Grammar for generating HTML code.
          cssgrammar: Grammar for generating CSS code.
          jsgrammar: Grammar for generating JS code.

        Returns:
          A string containing sample data.
        """

        result = self.template
        handlers = False
        while '<canvasfuzz>' in result:
            numlines = _N_MAIN_LINES
            if handlers:
                numlines = _N_EVENTHANDLER_LINES
            else:
                handlers = True
            result = result.replace(
                '<canvasfuzz>',
                self.generate_function_body(numlines),
                1
            )

        return result



def main():
    cherrypy.quickstart(DomFuzzer(os.path.dirname(__file__)))

if __name__ == '__main__':
    main()