#

# Copyright 21 May 2005 - (c) 2005 Jake Edge <jake@edge2.net>

# Copyright 2005-2007 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.

from __future__ import absolute_import

import cgi

import struct

from .common import (

    HTTP_OK,

)

from .. import (

    error,

    pycompat,

    util,

    wireproto,

)

stringio = util.stringio

urlerr = util.urlerr

urlreq = util.urlreq

HGTYPE = 'application/mercurial-0.1'

HGTYPE2 = 'application/mercurial-0.2'

HGERRTYPE = 'application/hg-error'

def decodevaluefromheaders(req, headerprefix):

    """Decode a long value from multiple HTTP request headers.

    Returns the value as a bytes, not a str.

    """

    chunks = []

    i = 1

    prefix = headerprefix.upper().replace(r'-', r'_')

    while True:

        v = req.env.get(r'HTTP_%s_%d' % (prefix, i))

        if v is None:

            break

        chunks.append(pycompat.bytesurl(v))

        i += 1

    return ''.join(chunks)

class webproto(wireproto.abstractserverproto):

    def __init__(self, req, ui):

        self.req = req

        self.response = ''

        self.ui = ui

        self.name = 'http'

    def getargs(self, args):

        knownargs = self._args()

        data = {}

        keys = args.split()

        for k in keys:

            if k == '*':

                star = {}

                for key in knownargs.keys():

                    if key != 'cmd' and key not in keys:

                        star[key] = knownargs[key][0]

                data['*'] = star

            else:

                data[k] = knownargs[k][0]

        return [data[k] for k in keys]

    def _args(self):

        args = self.req.form.copy()

        if pycompat.ispy3:

            args = {k.encode('ascii'): [v.encode('ascii') for v in vs]

                    for k, vs in args.items()}

        postlen = int(self.req.env.get(r'HTTP_X_HGARGS_POST', 0))

        if postlen:

            args.update(cgi.parse_qs(

                self.req.read(postlen), keep_blank_values=True))

            return args

        argvalue = decodevaluefromheaders(self.req, r'X-HgArg')

        args.update(cgi.parse_qs(argvalue, keep_blank_values=True))

        return args

    def getfile(self, fp):

        length = int(self.req.env[r'CONTENT_LENGTH'])

        # If httppostargs is used, we need to read Content-Length

        # minus the amount that was consumed by args.

        length -= int(self.req.env.get(r'HTTP_X_HGARGS_POST', 0))

        for s in util.filechunkiter(self.req, limit=length):

            fp.write(s)

    def redirect(self):

        self.oldio = self.ui.fout, self.ui.ferr

        self.ui.ferr = self.ui.fout = stringio()

    def restore(self):

        val = self.ui.fout.getvalue()

        self.ui.ferr, self.ui.fout = self.oldio

        return val

    def _client(self):

        return 'remote:%s:%s:%s' % (

            self.req.env.get('wsgi.url_scheme') or 'http',

            urlreq.quote(self.req.env.get('REMOTE_HOST', '')),

            urlreq.quote(self.req.env.get('REMOTE_USER', '')))

    def responsetype(self, prefer_uncompressed):

        """Determine the appropriate response type and compression settings.

        Returns a tuple of (mediatype, compengine, engineopts).

        """

        # Determine the response media type and compression engine based

        # on the request parameters.

        protocaps = decodevaluefromheaders(self.req, r'X-HgProto').split(' ')

        if '0.2' in protocaps:

            # All clients are expected to support uncompressed data.

            if prefer_uncompressed:

                return HGTYPE2, util._noopengine(), {}

            # Default as defined by wire protocol spec.

            compformats = ['zlib', 'none']

            for cap in protocaps:

                if cap.startswith('comp='):

                    compformats = cap[5:].split(',')

                    break

            # Now find an agreed upon compression format.

            for engine in wireproto.supportedcompengines(self.ui, self,

                                                         util.SERVERROLE):

                if engine.wireprotosupport().name in compformats:

                    opts = {}

                    level = self.ui.configint('server',

                                              '%slevel' % engine.name())

                    if level is not None:

                        opts['level'] = level

                    return HGTYPE2, engine, opts

            # No mutually supported compression format. Fall back to the

            # legacy protocol.

        # Don't allow untrusted settings because disabling compression or

        # setting a very high compression level could lead to flooding

        # the server's network or CPU.

        opts = {'level': self.ui.configint('server', 'zliblevel')}

        return HGTYPE, util.compengines['zlib'], opts

def iscmd(cmd):

    return cmd in wireproto.commands

def call(repo, req, cmd):

    p = webproto(req, repo.ui)

    def genversion2(gen, engine, engineopts):

        # application/mercurial-0.2 always sends a payload header

        # identifying the compression engine.

        name = engine.wireprotosupport().name

        assert 0 < len(name) < 256

        yield struct.pack('B', len(name))

        yield name

        for chunk in gen:

            yield chunk

    rsp = wireproto.dispatch(repo, p, cmd)

    if isinstance(rsp, bytes):

        req.respond(HTTP_OK, HGTYPE, body=rsp)

        return []

    elif isinstance(rsp, wireproto.streamres_legacy):

        gen = rsp.gen

        req.respond(HTTP_OK, HGTYPE)

        return gen

    elif isinstance(rsp, wireproto.streamres):

        gen = rsp.gen

        # This code for compression should not be streamres specific. It

        # is here because we only compress streamres at the moment.

        mediatype, engine, engineopts = p.responsetype(rsp.prefer_uncompressed)

        gen = engine.compressstream(gen, engineopts)

        if mediatype == HGTYPE2:

            gen = genversion2(gen, engine, engineopts)

        req.respond(HTTP_OK, mediatype)

        return gen

    elif isinstance(rsp, wireproto.pushres):

        val = p.restore()

        rsp = '%d\n%s' % (rsp.res, val)

        req.respond(HTTP_OK, HGTYPE, body=rsp)

        return []

    elif isinstance(rsp, wireproto.pusherr):

        # drain the incoming bundle

        req.drain()

        p.restore()

        rsp = '0\n%s\n' % rsp.res

        req.respond(HTTP_OK, HGTYPE, body=rsp)

        return []

    elif isinstance(rsp, wireproto.ooberror):

        rsp = rsp.message

        req.respond(HTTP_OK, HGERRTYPE, body=rsp)

        return []

    raise error.ProgrammingError('hgweb.protocol internal failure', rsp)