#!/bin/env python

import os
import subprocess
import shutil
import nbformat
################################################################


class NotFoundNotebooks(Exception):
            "Could not find the notebooks to treat"

################################################################


def mergeNotebooks(notebook_files, add_cell_number=False, select_cells=None):

    "Merges several notebooks in a single one named: talk.ipynb"
    print("Merging notebooks {0}".format(notebook_files))
    notebooks = [nbformat.read(f, as_version=4) for f in notebook_files]

    if len(notebooks) == 0:
        raise NotFoundNotebooks

    cells = notebooks[0]['cells']
    for n in notebooks[1:]:
        cells += n['cells']

    if select_cells is None:
        select_cells = set(range(0, len(cells)))

    select_cells = set(select_cells)

    discard_cells = set(range(0, len(cells))) - select_cells

    new_cells = []
    for cell_number, c in enumerate(cells):
        if cell_number in discard_cells:
            continue
        # print(c)
        new_cells.append(c)
        if add_cell_number:
            new_cell = nbformat.notebooknode.NotebookNode()
            new_cell['cell_type'] = 'markdown'
            new_cell['source'] = 'Cell number {0}'.format(cell_number)
            new_cell['metadata'] = {}
            new_cells.append(new_cell)
        # print(new_cells)
    notebooks[0]['cells'] = new_cells

        
    nbformat.write(notebooks[0], 'talk.ipynb')

################################################################


def launchSlideServer(options=""):

    " Launch the HTTP server for reveal slides "
    reveal_path = './reveal.js'
    dir_name = os.path.dirname(__file__)
    slides_config_file = os.path.join(dir_name, 'slides_config.py')
    cmd = ('jupyter nbconvert --to=slides --config {1} --post serve ' +
          '--ServePostProcessor.open_in_browser=False --reveal-prefix={0} {2} ' +
          'talk.ipynb').format(reveal_path, slides_config_file, options)

    print cmd
    subprocess.call(cmd, shell=True)

################################################################


def generateHTML(options=""):

    " Launch the HTTP server for reveal slides "
    reveal_path = './reveal.js'
    dir_name = os.path.dirname(__file__)
    slides_config_file = os.path.join(dir_name, 'slides_config.py')
    cmd = ('jupyter nbconvert --to=slides --config {1} --reveal-prefix={0} {2} ' +
          'talk.ipynb').format(reveal_path, slides_config_file, options)

    print cmd
    subprocess.call(cmd, shell=True)


################################################################

def executeNotebook(filename, options=""):
    " Request the execution of all cells "
    print 'execute notebook: ', filename
    dir_name = os.path.dirname(__file__)
    slides_config_file = os.path.join(dir_name, 'slides_execute_config.py')
    subprocess.call('jupyter nbconvert --to=notebook --output tmp.ipynb --config' +
                    ' {0} {1}'.format(slides_config_file, filename), shell=True)
    shutil.move('tmp.ipynb', filename)
    subprocess.call('jupyter trust {0}'.format(filename), shell=True)

################################################################