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

# Copyright(C) 2010-2012 Romain Bignon
#
# This file is part of weboob.
#
# weboob is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# weboob is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with weboob. If not, see <http://www.gnu.org/licenses/>.

from __future__ import with_statement

import tarfile
import posixpath
import shutil
import re
import sys
import os
from datetime import datetime
from contextlib import closing

from .modules import Module
from weboob.tools.log import getLogger
from weboob.tools.misc import to_unicode
from weboob.tools.browser import StandardBrowser, BrowserUnavailable
from ConfigParser import RawConfigParser, DEFAULTSECT

class ModuleInfo(object):
    def __init__(self, name):
        self.name = name

        # path to the local directory containing this module.
        self.path = None
        self.url = None

        self.version = 0
        self.capabilities = ()
        self.description = u''
        self.maintainer = u''
        self.license = u''
        self.icon = u''
        self.urls = u''

    def load(self, items):
        self.version = int(items['version'])
        self.capabilities = items['capabilities'].split()
        self.description = to_unicode(items['description'])
        self.maintainer = to_unicode(items['maintainer'])
        self.license = to_unicode(items['license'])
        self.icon = items['icon']
        self.urls = items['urls']

    def has_caps(self, caps):
        if not isinstance(caps, (list,tuple)):
            caps = [caps]
        for c in caps:
            if type(c) == type:
                c = c.__name__
            if c in self.capabilities:
                return True
        return False

    def is_installed(self):
        return self.path is not None

    def is_local(self):
        return self.url is None

    def dump(self):
        return (('version', self.version),
                ('capabilities', ' '.join(self.capabilities)),
                ('description', self.description),
                ('maintainer', self.maintainer),
                ('license', self.license),
                ('icon', self.icon),
                ('urls', self.urls),
               )

class RepositoryUnavailable(Exception):
    pass

class Repository(object):
    INDEX = 'modules.list'

    def __init__(self, url):
        self.url = url
        self.name = u''
        self.update = 0
        self.maintainer = u''
        self.local = None

        self.modules = {}

        if self.url.startswith('file://'):
            self.local = True
        elif re.match('https?://.*', self.url):
            self.local = False
        else:
            # This is probably a file in ~/.weboob/repositories/, we
            # don't know if this is a local or a remote repository.
            with open(self.url, 'r') as fp:
                self.parse_index(fp)

    def localurl2path(self):
        """
        Get a local path of a file:// URL.
        """
        assert self.local == True

        if self.url.startswith('file://'):
            return self.url[len('file://'):]
        return self.url

    def retrieve_index(self, dest_path):
        """
        Retrieve the index file of this repository. It can use network
        if this is a remote repository.

        @param dest_path [str]  path to save the downloaded index file.
        """
        if self.local:
            # Repository is local, open the file.
            filename = os.path.join(self.localurl2path(), self.INDEX)
            try:
                fp = open(filename, 'r')
            except IOError, e:
                # This local repository doesn't contain a built modules.list index.
                self.name = self.url.replace(os.path.sep, '_')
                self.build_index(self.localurl2path(), filename)
                fp = open(filename, 'r')
        else:
            # This is a remote repository, download file
            browser = StandardBrowser()
            try:
                fp = browser.openurl(posixpath.join(self.url, self.INDEX))
            except BrowserUnavailable, e:
                raise RepositoryUnavailable(unicode(e))

        self.parse_index(fp)

        if self.local:
            # Always rebuild index of a local repository.
            self.build_index(self.localurl2path(), filename)

        # Save the repository index in ~/.weboob/repositories/
        self.save(dest_path, private=True)

    def parse_index(self, fp):
        """
        Parse index of a repository

        @param fp [buffer]  file descriptor to read
        """
        config = RawConfigParser()
        config.readfp(fp)

        # Read default parameters
        items = dict(config.items(DEFAULTSECT))
        try:
            self.name = items['name']
            self.update = int(items['update'])
            self.maintainer = items['maintainer']
        except KeyError, e:
            raise RepositoryUnavailable('Missing global parameters in repository: %s' % e)
        except ValueError, e:
            raise RepositoryUnavailable('Incorrect value in repository parameters: %s' % e)

        if len(self.name) == 0:
            raise RepositoryUnavailable('Name is empty')

        if 'url' in items:
            self.url = items['url']
            self.local = self.url.startswith('file://')
        elif self.local is None:
            raise RepositoryUnavailable('Missing "url" key in settings')

        # Load modules
        self.modules.clear()
        for section in config.sections():
            module = ModuleInfo(section)
            module.load(dict(config.items(section)))
            if not self.local:
                module.url = posixpath.join(self.url, '%s.tar.gz' % module.name)
            self.modules[section] = module

    def build_index(self, path, filename):
        """
        Rebuild index of modules of repository.

        @param path [str]  path of the repository
        @param filename [str]  file to save index
        """
        print 'Rebuild index'
        self.modules.clear()

        sys.path.append(path)
        for name in sorted(os.listdir(path)):
            module_path = os.path.join(path, name)
            if not os.path.isdir(module_path) or '.' in name:
                continue

            try:
                module = Module(__import__(name, fromlist=[str(name)]))
            except Exception, e:
                print >>sys.stderr, 'ERROR: %s' % e
            else:
                m = ModuleInfo(module.name)
                m.version = self.get_tree_mtime(module_path)
                m.capabilities = [c.__name__ for c in module.iter_caps()]
                m.description = module.description
                m.maintainer = module.maintainer
                m.license = module.license
                m.icon = module.icon or ''
                self.modules[module.name] = m
        sys.path.remove(path)

        self.update = int(datetime.now().strftime('%Y%m%d%H%M'))
        self.save(filename)

    @staticmethod
    def get_tree_mtime(path, include_root=False):
        mtime = 0
        if include_root:
            mtime = int(datetime.fromtimestamp(os.path.getmtime(path)).strftime('%Y%m%d%H%M'))
        for root, dirs, files in os.walk(path):
            for f in files:
                if f.endswith('.pyc'):
                    continue
                m = int(datetime.fromtimestamp(os.path.getmtime(os.path.join(root, f))).strftime('%Y%m%d%H%M'))
                mtime = max(mtime, m)

        return mtime

    def save(self, filename, private=False):
        """
        Save repository into a file (modules.list for example).

        @param filename [str]  path to file to save repository.
        @param private [bool]  if enabled, save URL of repository.
        """
        config = RawConfigParser()
        config.set(DEFAULTSECT, 'name', self.name)
        config.set(DEFAULTSECT, 'update', self.update)
        config.set(DEFAULTSECT, 'maintainer', self.maintainer)
        if private:
            config.set(DEFAULTSECT, 'url', self.url)

        for module in self.modules.itervalues():
            config.add_section(module.name)
            for key, value in module.dump():
                config.set(module.name, key, to_unicode(value).encode('utf-8'))

        with open(filename, 'wb') as f:
            config.write(f)

class Versions(object):
    VERSIONS_LIST = 'versions.list'

    def __init__(self, path):
        self.path = path
        self.versions = {}

        try:
            with open(os.path.join(self.path, self.VERSIONS_LIST), 'r') as fp:
                config = RawConfigParser()
                config.readfp(fp)

                # Read default parameters
                for key, value in config.items(DEFAULTSECT):
                    self.versions[key] = int(value)
        except IOError:
            pass

    def get(self, name):
        return self.versions.get(name, None)

    def set(self, name, version):
        self.versions[name] = int(version)
        self.save()

    def save(self):
        config = RawConfigParser()
        for name, version in self.versions.iteritems():
            config.set(DEFAULTSECT, name, version)
        with open(os.path.join(self.path, self.VERSIONS_LIST), 'wb') as fp:
            config.write(fp)

class IProgress:
    def progress(self, percent, message):
        print '=== [%3.0f%%] %s' % (percent*100, message)

class ModuleInstallError(Exception):
    pass

DEFAULT_SOURCES_LIST = \
"""# List of Weboob repositories
#
# The entries below override the entries above (with
# backends of the same name).

http://updates.weboob.org/%(version)s/main/

# To enable Not Safe For Work backends, uncomment the
# following line:
#http://updates.weboob.org/%(version)s/nsfw/

# DEVELOPMENT
# If you want to hack on Weboob modules, you may add a
# reference to sources, for example:
#file:///home/rom1/src/weboob/modules/
"""

class Repositories(object):
    SOURCES_LIST = 'sources.list'
    MODULES_DIR = 'modules'
    REPOSITORIES_DIR = 'repositories'
    ICONS_DIR = 'icons'

    SHARE_DIRS = [MODULES_DIR, REPOSITORIES_DIR, ICONS_DIR]

    def __init__(self, workdir, datadir, version):
        self.logger = getLogger('repositories')
        self.version = version
        self.workdir = workdir
        self.datadir = datadir
        self.sources_list = os.path.join(self.workdir, self.SOURCES_LIST)
        self.modules_dir = os.path.join(self.datadir, self.MODULES_DIR)
        self.repos_dir = os.path.join(self.datadir, self.REPOSITORIES_DIR)
        self.icons_dir = os.path.join(self.datadir, self.ICONS_DIR)

        self.create_dir(self.datadir)
        self.create_dir(self.repos_dir)
        self.create_dir(self.modules_dir)
        self.create_dir(self.icons_dir)

        self.versions = Versions(self.modules_dir)

        self.repositories = []

        if not os.path.exists(self.sources_list):
            with open(self.sources_list, 'w') as f:
                f.write(DEFAULT_SOURCES_LIST)
            self.update()
        else:
            self.load()

    def create_dir(self, name):
        if not os.path.exists(name):
            os.makedirs(name)
        elif not os.path.isdir(name):
            self.logger.error(u'"%s" is not a directory' % name)

    def _extend_module_info(self, repos, info):
        if repos.local:
            info.path = repos.localurl2path()
        elif self.versions.get(info.name) is not None:
            info.path = self.modules_dir
        return info

    def get_all_modules_info(self, caps=None):
        """
        Get all ModuleInfo instances available.

        @param caps [list(str)]  Filter on capabilities.
        @return [dict(ModuleInfo)]
        """
        modules = {}
        for repos in reversed(self.repositories):
            for name, info in repos.modules.iteritems():
                if not name in modules and (not caps or info.has_caps(caps)):
                    modules[name] = self._extend_module_info(repos, info)
        return modules

    def get_module_info(self, name):
        """
        Get ModuleInfo object of a module.

        It tries all repositories from last to first, and set
        the 'path' attribute of ModuleInfo if it is installed.
        """
        for repos in reversed(self.repositories):
            if name in repos.modules:
                m = repos.modules[name]
                self._extend_module_info(repos, m)
                return m
        return None

    def load(self):
        """
        Load repositories from ~/.weboob/repositories/.
        """
        self.repositories = []
        for name in os.listdir(self.repos_dir):
            repository = Repository(os.path.join(self.repos_dir, name))
            self.repositories.append(repository)

    def retrieve_icon(self, module):
        """
        Retrieve the icon of a module and save it in ~/.weboob/icons/.
        """
        if not isinstance(module, ModuleInfo):
            module = self.get_module_info(module)

        dest_path = os.path.join(self.icons_dir, '%s.png' % module.name)

        if module.is_local():
            icon_path = os.path.join(module.path, module.name, 'favicon.png')
            if module.path and os.path.exists(icon_path):
                shutil.copy(icon_path, dest_path)
            return

        if module.icon:
            icon_url = module.icon
        else:
            icon_url = module.url.replace('.tar.gz', '.png')

        browser = StandardBrowser()
        try:
            icon = browser.openurl(icon_url)
        except BrowserUnavailable:
            pass # no icon, no problem
        else:
            with open(dest_path, 'wb') as fp:
                fp.write(icon.read())

    def update(self, progress=IProgress()):
        """
        Update list of repositories by downloading them
        and put them in ~/.weboob/repositories/.

        @param progress [IProgress]  observer object.
        """
        self.repositories = []
        for name in os.listdir(self.repos_dir):
            os.remove(os.path.join(self.repos_dir, name))

        with open(self.sources_list, 'r') as f:
            for line in f.xreadlines():
                line = line.strip() % {'version': self.version}
                m = re.match('(file|https?)://.*', line)
                if m:
                    print 'Getting %s' % line
                    repository = Repository(line)
                    dest_path = os.path.join(self.repos_dir, '%02d-%s' % (len(self.repositories),
                                                                          repository.url.replace(os.path.sep, '_')))
                    try:
                        repository.retrieve_index(dest_path)
                    except RepositoryUnavailable, e:
                        print >>sys.stderr, 'Error: %s' % e
                    else:
                        self.repositories.append(repository)

        to_update = []
        for name, info in self.get_all_modules_info().iteritems():
            if not info.is_local() and info.is_installed():
                to_update.append(info)

        class InstallProgress(IProgress):
            def __init__(self, n):
                self.n = n

            def progress(self, percent, message):
                progress.progress(float(self.n)/len(to_update) + 1.0/len(to_update)*percent, message)

        for n, info in enumerate(to_update):
            inst_progress = InstallProgress(n)
            try:
                self.install(info, inst_progress)
            except ModuleInstallError, e:
                inst_progress.progress(1.0, unicode(e))

    def install(self, module, progress=IProgress()):
        """
        Install a module.

        @paran module [str,ModuleInfo] module to install.
        @param progress [IProgress]  observer object.
        """
        if isinstance(module, ModuleInfo):
            info = module
        elif isinstance(module, basestring):
            progress.progress(0.0, 'Looking for module %s' % module)
            info = self.get_module_info(module)
            if not info:
                raise ModuleInstallError('Module "%s" does not exist' % module)
        else:
            raise ValueError('"module" parameter might be a ModuleInfo object or a string, not %r' % module)

        if info.is_local():
            raise ModuleInstallError('%s is available on local.' % info.name)

        installed = self.versions.get(info.name)
        if installed is None:
            progress.progress(0.3, 'Module is not installed yet')
        elif info.version > installed:
            progress.progress(0.3, 'A new version of this module is available')
        else:
            raise ModuleInstallError('The last version of %s is already installed' % info.name)

        browser = StandardBrowser()
        progress.progress(0.2, 'Downloading module...')
        try:
            fp = browser.openurl(info.url)
        except BrowserUnavailable, e:
            raise ModuleInstallError('Unable to fetch module: %s' % e)

        progress.progress(0.7, 'Setting up module...')

        # Extract module from tarball.
        with closing(tarfile.open('', 'r:gz', fp)) as tar:
            tar.extractall(self.modules_dir)

        self.versions.set(info.name, info.version)

        progress.progress(0.9, 'Downloading icon...')
        self.retrieve_icon(info)

        progress.progress(1.0, 'Module %s has been installed!' % info.name)