# coding: utf8
from __future__ import unicode_literals

import plac
import shutil
import requests
from pathlib import Path

from ..compat import path2str, json_dumps
from ..util import prints
from .. import util
from .. import about


@plac.annotations(
    input_dir=("directory with model data", "positional", None, str),
    output_dir=("output parent directory", "positional", None, str),
    meta=("path to meta.json", "option", "m", str),
    force=("force overwriting of existing folder in output directory", "flag", "f", bool)
)
def package(input_dir, output_dir, meta, force):
    """Generate Python package for model data, including meta and required
    installation files. A new directory will be created in the specified
    output directory, and model data will be copied over.
    """
    input_path = util.ensure_path(input_dir)
    output_path = util.ensure_path(output_dir)
    meta_path = util.ensure_path(meta)
    if not input_path or not input_path.exists():
        prints(input_path, title="Model directory not found", exits=1)
    if not output_path or not output_path.exists():
        prints(output_path, title="Output directory not found", exits=1)
    if meta_path and not meta_path.exists():
        prints(meta_path, title="meta.json not found", exits=1)

    template_setup = get_template('setup.py')
    template_manifest = get_template('MANIFEST.in')
    template_init = get_template('en_model_name/__init__.py')
    meta_path = meta_path or input_path / 'meta.json'
    if meta_path.is_file():
        prints(meta_path, title="Reading meta.json from file")
        meta = util.read_json(meta_path)
    else:
        meta = generate_meta()
    validate_meta(meta, ['lang', 'name', 'version'])

    model_name = meta['lang'] + '_' + meta['name']
    model_name_v = model_name + '-' + meta['version']
    main_path = output_path / model_name_v
    package_path = main_path / model_name

    create_dirs(package_path, force)
    shutil.copytree(path2str(input_path), path2str(package_path / model_name_v))
    create_file(main_path / 'meta.json', json_dumps(meta))
    create_file(main_path / 'setup.py', template_setup)
    create_file(main_path / 'MANIFEST.in', template_manifest)
    create_file(package_path / '__init__.py', template_init)
    prints(main_path, "To build the package, run `python setup.py sdist` in this "
           "directory.", title="Successfully created package '%s'" % model_name_v)


def create_dirs(package_path, force):
    if package_path.exists():
        if force:
            shutil.rmtree(path2str(package_path))
        else:
            prints(package_path, "Please delete the directory and try again, or "
                   "use the --force flag to overwrite existing directories.",
                   title="Package directory already exists", exits=1)
    Path.mkdir(package_path, parents=True)


def create_file(file_path, contents):
    file_path.touch()
    file_path.open('w', encoding='utf-8').write(contents)


def generate_meta():
    settings = [('lang', 'Model language', 'en'),
                ('name', 'Model name', 'model'),
                ('version', 'Model version', '0.0.0'),
                ('spacy_version', 'Required spaCy version', '>=2.0.0,<3.0.0'),
                ('description', 'Model description', False),
                ('author', 'Author', False),
                ('email', 'Author email', False),
                ('url', 'Author website', False),
                ('license', 'License', 'CC BY-NC 3.0')]

    prints("Enter the package settings for your model.", title="Generating meta.json")
    meta = {}
    for setting, desc, default in settings:
        response = util.get_raw_input(desc, default)
        meta[setting] = default if response == '' and default else response
    return meta


def validate_meta(meta, keys):
    for key in keys:
        if key not in meta or meta[key] == '':
            prints("This setting is required to build your package.",
                   title='No "%s" setting found in meta.json' % key, exits=1)


def get_template(filepath):
    r = requests.get(about.__model_files__ + filepath)
    if r.status_code != 200:
        prints("Couldn't fetch template files from GitHub.",
               title="Server error (%d)" % r.status_code, exits=1)
    return r.text