# Copyright 2011 Fog Creek Software

#

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

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

import os

import urllib2

from mercurial import error, httprepo, util, wireproto

from mercurial.i18n import _

import lfutil

LARGEFILES_REQUIRED_MSG = ('\nThis repository uses the largefiles extension.'

                           '\n\nPlease enable it in your Mercurial config '

                           'file.\n')

def putlfile(repo, proto, sha):

    '''Put a largefile into a repository's local store and into the

    user cache.'''

    proto.redirect()

    try:

        try:

                return wireproto.pushres(1)

            return wireproto.pushres(1)

    finally:

    return wireproto.pushres(0)

def getlfile(repo, proto, sha):

    '''Retrieve a largefile from the repository-local cache or system

    cache.'''

    filename = lfutil.findfile(repo, sha)

    if not filename:

        raise util.Abort(_('requested largefile %s not present in cache') % sha)

    f = open(filename, 'rb')

    length = os.fstat(f.fileno())[6]

    # Since we can't set an HTTP content-length header here, and

    # Mercurial core provides no way to give the length of a streamres

    # (and reading the entire file into RAM would be ill-advised), we

    # just send the length on the first line of the response, like the

    # ssh proto does for string responses.

    def generator():

        yield '%d\n' % length

        for chunk in f:

            yield chunk

    return wireproto.streamres(generator())

def statlfile(repo, proto, sha):

    '''Return '2\n' if the largefile is missing, '1\n' if it has a

    mismatched checksum, or '0\n' if it is in good condition'''

    filename = lfutil.findfile(repo, sha)

    if not filename:

        return '2\n'

    fd = None

    try:

        fd = open(filename, 'rb')

        return lfutil.hexsha1(fd) == sha and '0\n' or '1\n'

    finally:

        if fd:

            fd.close()

def wirereposetup(ui, repo):

    class lfileswirerepository(repo.__class__):

        def putlfile(self, sha, fd):

            # unfortunately, httprepository._callpush tries to convert its

            # input file-like into a bundle before sending it, so we can't use

            # it ...

            if issubclass(self.__class__, httprepo.httprepository):

                try:

                    return int(self._call('putlfile', data=fd, sha=sha,

                        headers={'content-type':'application/mercurial-0.1'}))

                except (ValueError, urllib2.HTTPError):

                    return 1

            # ... but we can't use sshrepository._call because the data=

            # argument won't get sent, and _callpush does exactly what we want

            # in this case: send the data straight through

            else:

                try:

                    ret, output = self._callpush("putlfile", fd, sha=sha)

                    if ret == "":

                        raise error.ResponseError(_('putlfile failed:'),

                                output)

                    return int(ret)

                except IOError:

                    return 1

                except ValueError:

                    raise error.ResponseError(

                        _('putlfile failed (unexpected response):'), ret)

        def getlfile(self, sha):

            stream = self._callstream("getlfile", sha=sha)

            length = stream.readline()

            try:

                length = int(length)

            except ValueError:

                self._abort(error.ResponseError(_("unexpected response:"),

                                                length))

            return (length, stream)

        def statlfile(self, sha):

            try:

                return int(self._call("statlfile", sha=sha))

            except (ValueError, urllib2.HTTPError):

                # If the server returns anything but an integer followed by a

                # newline, newline, it's not speaking our language; if we get

                # an HTTP error, we can't be sure the largefile is present;

                # either way, consider it missing.

                return 2

    repo.__class__ = lfileswirerepository

# advertise the largefiles=serve capability

def capabilities(repo, proto):

    return capabilities_orig(repo, proto) + ' largefiles=serve'

# duplicate what Mercurial's new out-of-band errors mechanism does, because

# clients old and new alike both handle it well

def webproto_refuseclient(self, message):

    self.req.header([('Content-Type', 'application/hg-error')])

    return message

def sshproto_refuseclient(self, message):

    self.ui.write_err('%s\n-\n' % message)

    self.fout.write('\n')

    self.fout.flush()

    return ''

def heads(repo, proto):

    if lfutil.islfilesrepo(repo):

        return wireproto.ooberror(LARGEFILES_REQUIRED_MSG)

    return wireproto.heads(repo, proto)

def sshrepo_callstream(self, cmd, **args):

    if cmd == 'heads' and self.capable('largefiles'):

        cmd = 'lheads'

    if cmd == 'batch' and self.capable('largefiles'):

        args['cmds'] = args['cmds'].replace('heads ', 'lheads ')

    return ssh_oldcallstream(self, cmd, **args)

def httprepo_callstream(self, cmd, **args):

    if cmd == 'heads' and self.capable('largefiles'):

        cmd = 'lheads'

    if cmd == 'batch' and self.capable('largefiles'):

        args['cmds'] = args['cmds'].replace('heads ', 'lheads ')

    return http_oldcallstream(self, cmd, **args)