# Copyright 2010-2011 Fog Creek Software

# Copyright 2010-2011 Unity Technologies

#

# This software may be used and distributed according to the terms of the

# GNU General Public License version 2 or any later version.

'''remote largefile store; the base class for wirestore'''

from __future__ import absolute_import

from mercurial.i18n import _

from mercurial import (

    error,

    util,

)

from mercurial.utils import (

    stringutil,

)

from . import (

    basestore,

    lfutil,

    localstore,

)

urlerr = util.urlerr

urlreq = util.urlreq

class remotestore(basestore.basestore):

    '''a largefile store accessed over a network'''

    def __init__(self, ui, repo, url):

        super(remotestore, self).__init__(ui, repo, url)

        self._lstore = None

        if repo is not None:

            self._lstore = localstore.localstore(self.ui, self.repo, self.repo)

    def put(self, source, hash):

        if self.sendfile(source, hash):

            raise error.Abort(

                _('remotestore: could not put %s to remote store %s')

                % (source, util.hidepassword(self.url)))

        self.ui.debug(

            _('remotestore: put %s to remote store %s\n')

            % (source, util.hidepassword(self.url)))

    def exists(self, hashes):

        return dict((h, s == 0) for (h, s) in # dict-from-generator

                    self._stat(hashes).iteritems())

    def sendfile(self, filename, hash):

        self.ui.debug('remotestore: sendfile(%s, %s)\n' % (filename, hash))

        try:

            with lfutil.httpsendfile(self.ui, filename) as fd:

                return self._put(hash, fd)

        except IOError as e:

            raise error.Abort(

                _('remotestore: could not open file %s: %s')

                % (filename, stringutil.forcebytestr(e)))

    def _getfile(self, tmpfile, filename, hash):

        try:

            chunks = self._get(hash)

        except urlerr.httperror as e:

            # 401s get converted to error.Aborts; everything else is fine being

            # turned into a StoreError

            raise basestore.StoreError(filename, hash, self.url,

                                       stringutil.forcebytestr(e))

        except urlerr.urlerror as e:

            # This usually indicates a connection problem, so don't

            # keep trying with the other files... they will probably

            # all fail too.

            raise error.Abort('%s: %s' %

                             (util.hidepassword(self.url), e.reason))

        except IOError as e:

            raise basestore.StoreError(filename, hash, self.url,

                                       stringutil.forcebytestr(e))

        return lfutil.copyandhash(chunks, tmpfile)

    def _hashesavailablelocally(self, hashes):

        existslocallymap = self._lstore.exists(hashes)

        localhashes = [hash for hash in hashes if existslocallymap[hash]]

        return localhashes

    def _verifyfiles(self, contents, filestocheck):

        failed = False

        expectedhashes = [expectedhash

                          for cset, filename, expectedhash in filestocheck]

        localhashes = self._hashesavailablelocally(expectedhashes)

        stats = self._stat([expectedhash for expectedhash in expectedhashes

                            if expectedhash not in localhashes])

        for cset, filename, expectedhash in filestocheck:

            if expectedhash in localhashes:

                filetocheck = (cset, filename, expectedhash)

                verifyresult = self._lstore._verifyfiles(contents,

                                                         [filetocheck])

                if verifyresult:

                    failed = True

            else:

                stat = stats[expectedhash]

                if stat:

                    if stat == 1:

                        self.ui.warn(

                            _('changeset %s: %s: contents differ\n')

                            % (cset, filename))

                        failed = True

                    elif stat == 2:

                        self.ui.warn(

                            _('changeset %s: %s missing\n')

                            % (cset, filename))

                        failed = True

                    else:

                        raise RuntimeError('verify failed: unexpected response '

                                           'from statlfile (%r)' % stat)

        return failed

    def _put(self, hash, fd):

        '''Put file with the given hash in the remote store.'''

        raise NotImplementedError('abstract method')

    def _get(self, hash):

        '''Get a iterator for content with the given hash.'''

        raise NotImplementedError('abstract method')

    def _stat(self, hashes):

        '''Get information about availability of files specified by

        hashes in the remote store. Return dictionary mapping hashes

        to return code where 0 means that file is available, other

        values if not.'''

        raise NotImplementedError('abstract method')