# -*- coding: utf-8 -*-

import os
import shlex
import shutil
import sys
import datetime

from invoke import task
from invoke.main import program
from invoke.util import cd
from pelican import main as pelican_main
from pelican.server import ComplexHTTPRequestHandler, RootedHTTPServer
from pelican.settings import DEFAULT_CONFIG, get_settings_from_file

SETTINGS_FILE_BASE = 'pelicanconf.py'
SETTINGS = {}
SETTINGS.update(DEFAULT_CONFIG)
LOCAL_SETTINGS = get_settings_from_file(SETTINGS_FILE_BASE)
SETTINGS.update(LOCAL_SETTINGS)

CONFIG = {
    'settings_base': SETTINGS_FILE_BASE,
    'settings_publish': 'publishconf.py',
    # Output path. Can be absolute or relative to tasks.py. Default: 'output'
    'deploy_path': SETTINGS['OUTPUT_PATH'],
    # Github Pages configuration
    'github_pages_branch': 'gh-pages',
    'commit_message': "'Publish site on {}'".format(datetime.date.today().isoformat()),
    # Host and port for `serve`
    'host': 'localhost',
    'port': 8000,
}

@task
def clean(c):
    """Remove generated files"""
    if os.path.isdir(CONFIG['deploy_path']):
        shutil.rmtree(CONFIG['deploy_path'])
        os.makedirs(CONFIG['deploy_path'])

@task
def build(c):
    """Build local version of site"""
    pelican_run('-s {settings_base}'.format(**CONFIG))

@task
def rebuild(c):
    """`build` with the delete switch"""
    pelican_run('-d -s {settings_base}'.format(**CONFIG))

@task
def regenerate(c):
    """Automatically regenerate site upon file modification"""
    pelican_run('-r -s {settings_base}'.format(**CONFIG))

@task
def serve(c):
    """Serve site at http://$HOST:$PORT/ (default is localhost:8000)"""

    class AddressReuseTCPServer(RootedHTTPServer):
        allow_reuse_address = True

    server = AddressReuseTCPServer(
        CONFIG['deploy_path'],
        (CONFIG['host'], CONFIG['port']),
        ComplexHTTPRequestHandler)

    sys.stderr.write('Serving at {host}:{port} ...\n'.format(**CONFIG))
    server.serve_forever()

@task
def reserve(c):
    """`build`, then `serve`"""
    build(c)
    serve(c)

@task
def preview(c):
    """Build production version of site"""
    pelican_run('-s {settings_publish}'.format(**CONFIG))

@task
def livereload(c):
    """Automatically reload browser tab upon file modification."""
    from livereload import Server

    def cached_build():
        cmd = '-s {settings_base} -e CACHE_CONTENT=True LOAD_CONTENT_CACHE=True'
        pelican_run(cmd.format(**CONFIG))

    cached_build()
    server = Server()
    theme_path = SETTINGS['THEME']
    watched_globs = [
        CONFIG['settings_base'],
        '{}/templates/**/*.html'.format(theme_path),
    ]

    content_file_extensions = ['.md', '.rst']
    for extension in content_file_extensions:
        content_glob = '{0}/**/*{1}'.format(SETTINGS['PATH'], extension)
        watched_globs.append(content_glob)

    static_file_extensions = ['.css', '.js']
    for extension in static_file_extensions:
        static_file_glob = '{0}/static/**/*{1}'.format(theme_path, extension)
        watched_globs.append(static_file_glob)

    for glob in watched_globs:
        server.watch(glob, cached_build)
    server.serve(host=CONFIG['host'], port=CONFIG['port'], root=CONFIG['deploy_path'])


@task
def publish(c):
    """Publish to production via rsync"""
    pelican_run('-s {settings_publish}'.format(**CONFIG))
    c.run(
        'rsync --delete --exclude ".DS_Store" -pthrvz -c '
        '-e "ssh -p {ssh_port}" '
        '{} {ssh_user}@{ssh_host}:{ssh_path}'.format(
            CONFIG['deploy_path'].rstrip('/') + '/',
            **CONFIG))

@task
def gh_pages(c):
    """Publish to GitHub Pages"""
    preview(c)
    c.run('ghp-import -b {github_pages_branch} '
          '-m {commit_message} '
          '{deploy_path} -p'.format(**CONFIG))

def pelican_run(cmd):
    cmd += ' ' + program.core.remainder  # allows to pass-through args to pelican
    pelican_main(shlex.split(cmd))