# sshserver.py - ssh protocol server support for mercurial

#

# Copyright 2005-2007 Matt Mackall <mpm@selenic.com>

# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>

#

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

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

from i18n import _

from node import bin, hex

import os, sys, tempfile, urllib, copy

class sshserver(object):

    caps = 'unbundle lookup changegroupsubset branchmap pushkey'.split()

    def __init__(self, ui, repo):

        self.ui = ui

        self.repo = repo

        self.lock = None

        self.fin = sys.stdin

        self.fout = sys.stdout

        hook.redirect(True)

        sys.stdout = sys.stderr

        # Prevent insertion/deletion of CRs

        util.set_binary(self.fin)

        util.set_binary(self.fout)

    def getargs(self, args):

        data = {}

        keys = args.split()

        count = len(keys)

        for n in xrange(len(keys)):

            argline = self.fin.readline()[:-1]

            arg, l = argline.split()

            val = self.fin.read(int(l))

            if arg not in keys:

                raise util.Abort("unexpected parameter %r" % arg)

            if arg == '*':

                star = {}

                for n in xrange(int(l)):

                    arg, l = argline.split()

                    val = self.fin.read(int(l))

                    star[arg] = val

                data['*'] = star

            else:

                data[arg] = val

        return [data[k] for k in keys]

    def getarg(self, name):

        return self.getargs(name)[0]

    def respond(self, v):

        self.fout.write("%d\n" % len(v))

        self.fout.write(v)

        self.fout.flush()

    def serve_forever(self):

        try:

            while self.serve_one():

                pass

        finally:

            if self.lock is not None:

                self.lock.release()

        sys.exit(0)

    def serve_one(self):

        cmd = self.fin.readline()[:-1]

            impl = getattr(self, 'do_' + cmd, None)

            if impl:

                r = impl()

                if r is not None:

                    self.respond(r)

            else: self.respond("")

        return cmd != ''

    def do_hello(self):

        '''the hello command returns a set of lines describing various

        interesting things about the server, in an RFC822-like format.

        Currently the only one defined is "capabilities", which

        consists of a line in the form:

        capabilities: space separated list of tokens

        '''

        caps = copy.copy(self.caps)

        if streamclone.allowed(self.repo.ui):

            caps.append('stream=%d' % self.repo.changelog.version)

        return "capabilities: %s\n" % (' '.join(caps),)

    def do_lock(self):

        '''DEPRECATED - allowing remote client to lock repo is not safe'''

        self.lock = self.repo.lock()

        return ""

    def do_unlock(self):

        '''DEPRECATED'''

        if self.lock:

            self.lock.release()

        self.lock = None

        return ""

    def do_changegroup(self):

        nodes = []

        roots = self.getarg('roots')

        nodes = map(bin, roots.split(" "))

        cg = self.repo.changegroup(nodes, 'serve')

        while True:

            d = cg.read(4096)

            if not d:

                break

            self.fout.write(d)

        self.fout.flush()

    def do_changegroupsubset(self):

        bases, heads = self.getargs('bases heads')

        bases = [bin(n) for n in bases.split(' ')]

        heads = [bin(n) for n in heads.split(' ')]

        cg = self.repo.changegroupsubset(bases, heads, 'serve')

        while True:

            d = cg.read(4096)

            if not d:

                break

            self.fout.write(d)

        self.fout.flush()

    def do_addchangegroup(self):

        '''DEPRECATED'''

        if not self.lock:

            self.respond("not locked")

            return

        self.respond("")

        r = self.repo.addchangegroup(self.fin, 'serve', self.client_url(),

                                     lock=self.lock)

        return str(r)

    def client_url(self):

        client = os.environ.get('SSH_CLIENT', '').split(' ', 1)[0]

        return 'remote:ssh:' + client

    def do_unbundle(self):

        their_heads = self.getarg('heads').split()

        def check_heads():

            heads = map(hex, self.repo.heads())

            return their_heads == [hex('force')] or their_heads == heads

        # fail early if possible

        if not check_heads():

            self.respond(_('unsynced changes'))

            return

        self.respond('')

        # write bundle data to temporary file because it can be big

        fd, tempname = tempfile.mkstemp(prefix='hg-unbundle-')

        fp = os.fdopen(fd, 'wb+')

        try:

            count = int(self.fin.readline())

            while count:

                fp.write(self.fin.read(count))

                count = int(self.fin.readline())

            was_locked = self.lock is not None

            if not was_locked:

                self.lock = self.repo.lock()

            try:

                if not check_heads():

                    # someone else committed/pushed/unbundled while we

                    # were transferring data

                    self.respond(_('unsynced changes'))

                    return

                self.respond('')

                # push can proceed

                fp.seek(0)

                r = self.repo.addchangegroup(fp, 'serve', self.client_url(),

                                             lock=self.lock)

                self.respond(str(r))

            finally:

                if not was_locked:

                    self.lock.release()

                    self.lock = None

        finally:

            fp.close()

            os.unlink(tempname)

    def do_stream_out(self):

        try:

            for chunk in streamclone.stream_out(self.repo):

                self.fout.write(chunk)

            self.fout.flush()

        except streamclone.StreamException, inst:

            self.fout.write(str(inst))

            self.fout.flush()