# Copyright (c) 2012 Roberto Alsina y otros.

# Permission is hereby granted, free of charge, to any
# person obtaining a copy of this software and associated
# documentation files (the "Software"), to deal in the
# Software without restriction, including without limitation
# the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the
# Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice
# shall be included in all copies or substantial portions of
# the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
# KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
# WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
# PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS
# OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
# OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
# OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
# SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

from __future__ import print_function
import os
import sys
try:
    from urllib import unquote
    from urlparse import urlparse
except ImportError:
    from urllib.parse import unquote, urlparse  # NOQA

import lxml.html

from nikola.plugin_categories import Command


class CommandCheck(Command):
    """Check the generated site."""

    name = "check"

    doc_usage = "-l [--find-sources] | -f"
    doc_purpose = "Check links and files in the generated site."
    cmd_options = [
        {
            'name': 'links',
            'short': 'l',
            'long': 'check-links',
            'type': bool,
            'default': False,
            'help': 'Check for dangling links',
        },
        {
            'name': 'files',
            'short': 'f',
            'long': 'check-files',
            'type': bool,
            'default': False,
            'help': 'Check for unknown files',
        },
        {
            'name': 'find_sources',
            'long': 'find-sources',
            'type': bool,
            'default': False,
            'help': 'List possible source files for files with broken links.',
        },
    ]

    def _execute(self, options, args):
        """Check the generated site."""
        if not options['links'] and not options['files']:
            print(self.help())
            return False
        if options['links']:
            failure = scan_links(options['find_sources'])
        if options['files']:
            failure = scan_files()
        if failure:
            sys.exit(1)

existing_targets = set([])


def analize(task, find_sources=False):
    rv = False
    try:
        filename = task.split(":")[-1]
        d = lxml.html.fromstring(open(filename).read())
        for l in d.iterlinks():
            target = l[0].attrib[l[1]]
            if target == "#":
                continue
            parsed = urlparse(target)
            if parsed.scheme:
                continue
            if parsed.fragment:
                target = target.split('#')[0]
            target_filename = os.path.abspath(
                os.path.join(os.path.dirname(filename), unquote(target)))
            if target_filename not in existing_targets:
                if os.path.exists(target_filename):
                    existing_targets.add(target_filename)
                else:
                    rv = True
                    print("Broken link in {0}: ".format(filename), target)
                    if find_sources:
                        print("Possible sources:")
                        print(os.popen('nikola list --deps ' + task,
                                       'r').read())
                        print("===============================\n")

    except Exception as exc:
        print("Error with:", filename, exc)
    return rv


def scan_links(find_sources=False):
    print("Checking Links:\n===============\n")
    failure = False
    for task in os.popen('nikola list --all', 'r').readlines():
        task = task.strip()
        if task.split(':')[0] in ('render_tags', 'render_archive',
                                  'render_galleries', 'render_indexes',
                                  'render_pages'
                                  'render_site') and '.html' in task:
            if analize(task, find_sources):
                failure = True
    return failure


def scan_files():
    print("Checking Files:\n===============\n")
    task_fnames = set([])
    real_fnames = set([])
    # First check that all targets are generated in the right places
    failure = False
    for task in os.popen('nikola list --all', 'r').readlines():
        task = task.strip()
        if 'output' in task and ':' in task:
            fname = task.split(':')[-1]
            task_fnames.add(fname)
     # And now check that there are no non-target files
    for root, dirs, files in os.walk('output'):
        for src_name in files:
            fname = os.path.join(root, src_name)
            real_fnames.add(fname)

    only_on_output = list(real_fnames - task_fnames)
    if only_on_output:
        only_on_output.sort()
        print("\nFiles from unknown origins:\n")
        for f in only_on_output:
            print(f)
        failure = True

    only_on_input = list(task_fnames - real_fnames)
    if only_on_input:
        only_on_input.sort()
        print("\nFiles not generated:\n")
        for f in only_on_input:
            print(f)

    return failure