"""Base classes for the notebook conversion pipeline.

This module defines Converter, from which all objects designed to implement
a conversion of IPython notebooks to some other format should inherit.
"""
#-----------------------------------------------------------------------------
# Copyright (c) 2012, the IPython Development Team.
#
# Distributed under the terms of the Modified BSD License.
#
# The full license is in the file COPYING.txt, distributed with this software.
#-----------------------------------------------------------------------------

#-----------------------------------------------------------------------------
# Imports
#-----------------------------------------------------------------------------

from __future__ import print_function, absolute_import

# Stdlib imports
import jinja2
import codecs
import io
import logging
import os
from IPython.utils import path
import pprint
import re
from types import FunctionType

from jinja2 import Environment, PackageLoader, FileSystemLoader
env = Environment(loader=FileSystemLoader('./templates/'))

# IPython imports
from IPython.nbformat import current as nbformat
from IPython.config.configurable import Configurable, SingletonConfigurable
from IPython.utils.traitlets import (List, Unicode, Type, Bool, Dict, CaselessStrEnum,
                                    Any)

# Our own imports
from IPython.utils.text import indent
from .utils import remove_ansi
from markdown import markdown
from .utils import highlight,ansi2html
#-----------------------------------------------------------------------------
# Class declarations
#-----------------------------------------------------------------------------
def rm_fake(strng):
    return strng.replace('/files/', '')

class ConversionException(Exception):
    pass


def python_comment(string):
    return '# '+'\n# '.join(string.split('\n'))



def header_body():
        """Return the body of the header as a list of strings."""

        from pygments.formatters import HtmlFormatter

        header = []
        static = os.path.join(path.get_ipython_package_dir(),
        'frontend', 'html', 'notebook', 'static',
        )
        here = os.path.split(os.path.realpath(__file__))[0]
        css = os.path.join(static, 'css')
        for sheet in [
            # do we need jquery and prettify?
            # os.path.join(static, 'jquery', 'css', 'themes', 'base',
            # 'jquery-ui.min.css'),
            # os.path.join(static, 'prettify', 'prettify.css'),
            os.path.join(css, 'boilerplate.css'),
            os.path.join(css, 'fbm.css'),
            os.path.join(css, 'notebook.css'),
            os.path.join(css, 'renderedhtml.css'),
            # our overrides:
            os.path.join(here, '..', 'css', 'static_html.css'),
        ]:

            with io.open(sheet, encoding='utf-8') as f:
                s = f.read()
                header.extend(s.split('\n'))

        pygments_css = HtmlFormatter().get_style_defs('.highlight')
        header.extend(pygments_css.split('\n'))
        return header

ecss = header_body()

env.filters['pycomment'] = python_comment
env.filters['indent'] = indent
env.filters['rm_fake'] = rm_fake
env.filters['rm_ansi'] = remove_ansi
env.filters['markdown'] = markdown
env.filters['highlight'] = highlight
env.filters['ansi2html'] = ansi2html

class ConverterTemplate(Configurable):

    display_data_priority = ['pdf', 'svg', 'png', 'jpg', 'text']
    #-------------------------------------------------------------------------
    # Instance-level attributes that are set in the constructor for this
    # class.
    #-------------------------------------------------------------------------
    infile = Any()


    infile_dir = Unicode()

    def __init__(self, tplfile='fullhtml', config=None, **kw):
        self.template = env.get_template(tplfile+'.tpl')
        super(ConverterTemplate,self).__init__(config=config)

    def _get_prompt_number(self, cell):
        return cell.prompt_number if hasattr(cell, 'prompt_number') \
            else self.blank_symbol


    def process(self):
        converted_cells = []
        for worksheet in self.nb.worksheets:
            for cell in worksheet.cells:
                cell.type = cell.cell_type
                cell.haspyout = False
                for out in cell.get('outputs',[]):
                    if out.output_type == 'pyout':
                        cell.haspyout = True
                        break
            converted_cells.append(worksheet)

        return converted_cells

    def convert(self, cell_separator='\n'):
        return self.template.render(worksheets=self.process(), ecss=ecss)


    def read(self, filename):
        "read and parse notebook into NotebookNode called self.nb"
        with io.open(filename) as f:
            self.nb = nbformat.read(f, 'json')