# wireproto.py - generic wire protocol support functions

#

# Copyright 2005-2010 Matt Mackall <mpm@selenic.com>

#

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

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

import urllib, tempfile, os, sys

from i18n import _

from node import bin, hex

import changegroup as changegroupmod

import repo, error, encoding, util, store

import pushkey as pushkeymod

# list of nodes encoding / decoding

def decodelist(l, sep=' '):

    return map(bin, l.split(sep))

def encodelist(l, sep=' '):

    return sep.join(map(hex, l))

# client side

class wirerepository(repo.repository):

    def lookup(self, key):

        self.requirecap('lookup', _('look up remote revision'))

        d = self._call("lookup", key=key)

        success, data = d[:-1].split(" ", 1)

        if int(success):

            return bin(data)

        self._abort(error.RepoError(data))

    def heads(self):

        d = self._call("heads")

        try:

            return decodelist(d[:-1])

        except:

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

    def branchmap(self):

        d = self._call("branchmap")

        try:

            branchmap = {}

            for branchpart in d.splitlines():

                branchname, branchheads = branchpart.split(' ', 1)

                branchname = urllib.unquote(branchname)

                # Earlier servers (1.3.x) send branch names in (their) local

                # charset. The best we can do is assume it's identical to our

                # own local charset, in case it's not utf-8.

                try:

                    branchname.decode('utf-8')

                except UnicodeDecodeError:

                    branchname = encoding.fromlocal(branchname)

                branchheads = decodelist(branchheads)

                branchmap[branchname] = branchheads

            return branchmap

        except TypeError:

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

    def branches(self, nodes):

        n = encodelist(nodes)

        d = self._call("branches", nodes=n)

        try:

            br = [tuple(decodelist(b)) for b in d.splitlines()]

            return br

        except:

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

    def between(self, pairs):

        batch = 8 # avoid giant requests

        r = []

        for i in xrange(0, len(pairs), batch):

            n = " ".join([encodelist(p, '-') for p in pairs[i:i + batch]])

            d = self._call("between", pairs=n)

            try:

                r.extend(l and decodelist(l) or [] for l in d.splitlines())

            except:

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

        return r

    def pushkey(self, namespace, key, old, new):

        if not self.capable('pushkey'):

            return False

        d = self._call("pushkey",

                      namespace=namespace, key=key, old=old, new=new)

        return bool(int(d))

    def listkeys(self, namespace):

        if not self.capable('pushkey'):

            return {}

        d = self._call("listkeys", namespace=namespace)

        r = {}

        for l in d.splitlines():

            k, v = l.split('\t')

            r[k.decode('string-escape')] = v.decode('string-escape')

        return r

    def stream_out(self):

        return self._callstream('stream_out')

    def changegroup(self, nodes, kind):

        n = encodelist(nodes)

        f = self._callstream("changegroup", roots=n)

        return changegroupmod.unbundle10(self._decompress(f), 'UN')

    def changegroupsubset(self, bases, heads, kind):

        self.requirecap('changegroupsubset', _('look up remote changes'))

        bases = encodelist(bases)

        heads = encodelist(heads)

        f = self._callstream("changegroupsubset",

                             bases=bases, heads=heads)

        return changegroupmod.unbundle10(self._decompress(f), 'UN')

    def unbundle(self, cg, heads, source):

        '''Send cg (a readable file-like object representing the

        changegroup to push, typically a chunkbuffer object) to the

        remote server as a bundle. Return an integer indicating the

        result of the push (see localrepository.addchangegroup()).'''

        ret, output = self._callpush("unbundle", cg, heads=encodelist(heads))

        if ret == "":

            raise error.ResponseError(

                _('push failed:'), output)

        try:

            ret = int(ret)

        except ValueError:

            raise error.ResponseError(

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

        for l in output.splitlines(True):

            self.ui.status(_('remote: '), l)

        return ret

# server side

class streamres(object):

    def __init__(self, gen):

        self.gen = gen

class pushres(object):

    def __init__(self, res):

        self.res = res

class pusherr(object):

    def __init__(self, res):

        self.res = res

def dispatch(repo, proto, command):

    func, spec = commands[command]

    args = proto.getargs(spec)

    return func(repo, proto, *args)

def between(repo, proto, pairs):

    pairs = [decodelist(p, '-') for p in pairs.split(" ")]

    r = []

    for b in repo.between(pairs):

        r.append(encodelist(b) + "\n")

    return "".join(r)

def branchmap(repo, proto):

    branchmap = repo.branchmap()

    heads = []

    for branch, nodes in branchmap.iteritems():

        branchname = urllib.quote(branch)

        branchnodes = encodelist(nodes)

        heads.append('%s %s' % (branchname, branchnodes))

    return '\n'.join(heads)

def branches(repo, proto, nodes):

    nodes = decodelist(nodes)

    r = []

    for b in repo.branches(nodes):

        r.append(encodelist(b) + "\n")

    return "".join(r)

def capabilities(repo, proto):

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

    if _allowstream(repo.ui):

        requiredformats = repo.requirements & repo.supportedformats

        # if our local revlogs are just revlogv1, add 'stream' cap

        if not requiredformats - set(('revlogv1',)):

            caps.append('stream')

        # otherwise, add 'streamreqs' detailing our local revlog format

        else:

            caps.append('streamreqs=%s' % ','.join(requiredformats))

    caps.append('unbundle=%s' % ','.join(changegroupmod.bundlepriority))

    return ' '.join(caps)

def changegroup(repo, proto, roots):

    nodes = decodelist(roots)

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

    return streamres(proto.groupchunks(cg))

def changegroupsubset(repo, proto, bases, heads):

    bases = decodelist(bases)

    heads = decodelist(heads)

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

    return streamres(proto.groupchunks(cg))

def heads(repo, proto):

    h = repo.heads()

    return encodelist(h) + "\n"

def hello(repo, proto):

    '''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

    '''

    return "capabilities: %s\n" % (capabilities(repo, proto))

def listkeys(repo, proto, namespace):

    d = pushkeymod.list(repo, namespace).items()

    t = '\n'.join(['%s\t%s' % (k.encode('string-escape'),

                               v.encode('string-escape')) for k, v in d])

    return t

def lookup(repo, proto, key):

    try:

        r = hex(repo.lookup(key))

        success = 1

    except Exception, inst:

        r = str(inst)

        success = 0

    return "%s %s\n" % (success, r)

def pushkey(repo, proto, namespace, key, old, new):

    r = pushkeymod.push(repo, namespace, key, old, new)

    return '%s\n' % int(r)

def _allowstream(ui):

    return ui.configbool('server', 'uncompressed', True, untrusted=True)

def stream(repo, proto):

    '''If the server supports streaming clone, it advertises the "stream"

    capability with a value representing the version and flags of the repo

    it is serving. Client checks to see if it understands the format.

    The format is simple: the server writes out a line with the amount

    of files, then the total amount of bytes to be transfered (separated

    by a space). Then, for each file, the server first writes the filename

    and filesize (separated by the null character), then the file contents.

    '''

    if not _allowstream(repo.ui):

        return '1\n'

    entries = []

    total_bytes = 0

    try:

        # get consistent snapshot of repo, lock during scan

        lock = repo.lock()

        try:

            repo.ui.debug('scanning\n')

            for name, ename, size in repo.store.walk():

                entries.append((name, size))

                total_bytes += size

        finally:

            lock.release()

    except error.LockError:

        return '2\n' # error: 2

    def streamer(repo, entries, total):

        '''stream out all metadata files in repository.'''

        yield '0\n' # success

        repo.ui.debug('%d files, %d bytes to transfer\n' %

                      (len(entries), total_bytes))

        yield '%d %d\n' % (len(entries), total_bytes)

        for name, size in entries:

            repo.ui.debug('sending %s (%d bytes)\n' % (name, size))

            # partially encode name over the wire for backwards compat

            yield '%s\0%d\n' % (store.encodedir(name), size)

            for chunk in util.filechunkiter(repo.sopener(name), limit=size):

                yield chunk

    return streamres(streamer(repo, entries, total_bytes))

def unbundle(repo, proto, heads):

    their_heads = decodelist(heads)

    def check_heads():

        heads = repo.heads()

        return their_heads == ['force'] or their_heads == heads

    proto.redirect()

    # fail early if possible

    if not check_heads():

        return pusherr('unsynced changes')

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

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

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

    r = 0

    try:

        proto.getfile(fp)

        lock = repo.lock()

        try:

            if not check_heads():

                # someone else committed/pushed/unbundled while we

                # were transferring data

                return pusherr('unsynced changes')

            # push can proceed

            fp.seek(0)

            gen = changegroupmod.readbundle(fp, None)

            try:

                r = repo.addchangegroup(gen, 'serve', proto._client(),

                                        lock=lock)

            except util.Abort, inst:

                sys.stderr.write("abort: %s\n" % inst)

        finally:

            lock.release()

        return pushres(r)

    finally:

        fp.close()

        os.unlink(tempname)

commands = {

    'between': (between, 'pairs'),

    'branchmap': (branchmap, ''),

    'branches': (branches, 'nodes'),

    'capabilities': (capabilities, ''),

    'changegroup': (changegroup, 'roots'),

    'changegroupsubset': (changegroupsubset, 'bases heads'),

    'heads': (heads, ''),

    'hello': (hello, ''),

    'listkeys': (listkeys, 'namespace'),

    'lookup': (lookup, 'key'),

    'pushkey': (pushkey, 'namespace key old new'),

    'stream_out': (stream, ''),

    'unbundle': (unbundle, 'heads'),

}