# patch.py - patch file parsing routines

#

# Copyright 2006 Brendan Cully <brendan@kublai.com>

#

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

# of the GNU General Public License, incorporated herein by reference.

from i18n import _

from node import *

import base85, cmdutil, mdiff, util, context, revlog

import cStringIO, email.Parser, os, popen2, re, sha

import sys, tempfile, zlib

# helper functions

def copyfile(src, dst, basedir=None):

    if not basedir:

        basedir = os.getcwd()

    abssrc, absdst = [os.path.join(basedir, n) for n in (src, dst)]

    if os.path.exists(absdst):

        raise util.Abort(_("cannot create %s: destination already exists") %

                         dst)

    targetdir = os.path.dirname(absdst)

    if not os.path.isdir(targetdir):

        os.makedirs(targetdir)

    util.copyfile(abssrc, absdst)

# public functions

def extract(ui, fileobj):

    '''extract patch from data read from fileobj.

    # attempt to detect the start of a patch

    # (this heuristic is borrowed from quilt)

    diffre = re.compile(r'^(?:Index:[ \t]|diff[ \t]|RCS file: |' +

                        'retrieving revision [0-9]+(\.[0-9]+)*$|' +

                        '(---|\*\*\*)[ \t])', re.MULTILINE)

    fd, tmpname = tempfile.mkstemp(prefix='hg-patch-')

    tmpfp = os.fdopen(fd, 'w')

    try:

        msg = email.Parser.Parser().parse(fileobj)

        message = msg['Subject']

        user = msg['From']

        # should try to parse msg['Date']

        date = None

        if message:

            if message.startswith('[PATCH'):

                pend = message.find(']')

                if pend >= 0:

                    message = message[pend+1:].lstrip()

            message = message.replace('\n\t', ' ')

            ui.debug('Subject: %s\n' % message)

        if user:

            ui.debug('From: %s\n' % user)

        diffs_seen = 0

        ok_types = ('text/plain', 'text/x-diff', 'text/x-patch')

        for part in msg.walk():

            content_type = part.get_content_type()

            ui.debug('Content-Type: %s\n' % content_type)

            if content_type not in ok_types:

                continue

            payload = part.get_payload(decode=True)

            m = diffre.search(payload)

            if m:

                hgpatch = False

                ignoretext = False

                ui.debug(_('found patch at byte %d\n') % m.start(0))

                diffs_seen += 1

                cfp = cStringIO.StringIO()

                if message:

                    cfp.write(message)

                    cfp.write('\n')

                for line in payload[:m.start(0)].splitlines():

                    if line.startswith('# HG changeset patch'):

                        ui.debug(_('patch generated by hg export\n'))

                        hgpatch = True

                        # drop earlier commit message content

                        cfp.seek(0)

                        cfp.truncate()

                    elif hgpatch:

                        if line.startswith('# User '):

                            user = line[7:]

                            ui.debug('From: %s\n' % user)

                        elif line.startswith("# Date "):

                            date = line[7:]

                    elif line == '---' and 'git-send-email' in msg['X-Mailer']:

                        ignoretext = True

                    if not line.startswith('# ') and not ignoretext:

                        cfp.write(line)

                        cfp.write('\n')

                message = cfp.getvalue()

                if tmpfp:

                    tmpfp.write(payload)

                    if not payload.endswith('\n'):

                        tmpfp.write('\n')

            elif not diffs_seen and message and content_type == 'text/plain':

                message += '\n' + payload

    except:

        tmpfp.close()

        os.unlink(tmpname)

        raise

    tmpfp.close()

    if not diffs_seen:

        os.unlink(tmpname)

GP_PATCH  = 1 << 0  # we have to run patch

GP_FILTER = 1 << 1  # there's some copy/rename operation

GP_BINARY = 1 << 2  # there's a binary patch

def readgitpatch(patchname):

    """extract git-style metadata about patches from <patchname>"""

    class gitpatch:

        "op is one of ADD, DELETE, RENAME, MODIFY or COPY"

        def __init__(self, path):

            self.path = path

            self.oldpath = None

            self.mode = None

            self.op = 'MODIFY'

            self.copymod = False

            self.lineno = 0

            self.binary = False

    # Filter patch for git information

    gitre = re.compile('diff --git a/(.*) b/(.*)')

    pf = file(patchname)

    gp = None

    gitpatches = []

    # Can have a git patch with only metadata, causing patch to complain

    dopatch = 0

    lineno = 0

    for line in pf:

        lineno += 1

        if line.startswith('diff --git'):

            m = gitre.match(line)

            if m:

                if gp:

                    gitpatches.append(gp)

                src, dst = m.group(1, 2)

                gp = gitpatch(dst)

                gp.lineno = lineno

        elif gp:

            if line.startswith('--- '):

                if gp.op in ('COPY', 'RENAME'):

                    gp.copymod = True

                    dopatch |= GP_FILTER

                gitpatches.append(gp)

                gp = None

                dopatch |= GP_PATCH

                continue

            if line.startswith('rename from '):

                gp.op = 'RENAME'

                gp.oldpath = line[12:].rstrip()

            elif line.startswith('rename to '):

                gp.path = line[10:].rstrip()

            elif line.startswith('copy from '):

                gp.op = 'COPY'

                gp.oldpath = line[10:].rstrip()

            elif line.startswith('copy to '):

                gp.path = line[8:].rstrip()

            elif line.startswith('deleted file'):

                gp.op = 'DELETE'

            elif line.startswith('new file mode '):

                gp.op = 'ADD'

                gp.mode = int(line.rstrip()[-3:], 8)

            elif line.startswith('new mode '):

                gp.mode = int(line.rstrip()[-3:], 8)

            elif line.startswith('GIT binary patch'):

                dopatch |= GP_BINARY

                gp.binary = True

    if gp:

        gitpatches.append(gp)

    if not gitpatches:

        dopatch = GP_PATCH

    return (dopatch, gitpatches)

def dogitpatch(patchname, gitpatches, cwd=None):

    """Preprocess git patch so that vanilla patch can handle it"""

    def extractbin(fp):

        i = [0] # yuck

        def readline():

            i[0] += 1

            return fp.readline().rstrip()

        line = readline()

        while line and not line.startswith('literal '):

            line = readline()

        if not line:

            return None, i[0]

        size = int(line[8:])

        dec = []

        line = readline()

        while line:

            l = line[0]

            if l <= 'Z' and l >= 'A':

                l = ord(l) - ord('A') + 1

            else:

                l = ord(l) - ord('a') + 27

            dec.append(base85.b85decode(line[1:])[:l])

            line = readline()

        text = zlib.decompress(''.join(dec))

        if len(text) != size:

            raise util.Abort(_('binary patch is %d bytes, not %d') %

                             (len(text), size))

        return text, i[0]

    pf = file(patchname)

    pfline = 1

    fd, patchname = tempfile.mkstemp(prefix='hg-patch-')

    tmpfp = os.fdopen(fd, 'w')

    try:

        for i in xrange(len(gitpatches)):

            p = gitpatches[i]

            if not p.copymod and not p.binary:

                continue

            # rewrite patch hunk

            while pfline < p.lineno:

                tmpfp.write(pf.readline())

                pfline += 1

            if p.binary:

                text, delta = extractbin(pf)

                if not text:

                    raise util.Abort(_('binary patch extraction failed'))

                pfline += delta

                if not cwd:

                    cwd = os.getcwd()

                absdst = os.path.join(cwd, p.path)

                basedir = os.path.dirname(absdst)

                if not os.path.isdir(basedir):

                    os.makedirs(basedir)

                out = file(absdst, 'wb')

                out.write(text)

                out.close()

            elif p.copymod:

                copyfile(p.oldpath, p.path, basedir=cwd)

                tmpfp.write('diff --git a/%s b/%s\n' % (p.path, p.path))

                line = pf.readline()

                pfline += 1

                while not line.startswith('--- a/'):

                    tmpfp.write(line)

                    line = pf.readline()

                    pfline += 1

                tmpfp.write('--- a/%s\n' % p.path)

        line = pf.readline()

        while line:

            tmpfp.write(line)

            line = pf.readline()

    except:

        tmpfp.close()

        os.unlink(patchname)

        raise

    tmpfp.close()

    return patchname

def patch(patchname, ui, strip=1, cwd=None, files={}):

    """apply the patch <patchname> to the working directory.

    a list of patched files is returned"""

    # helper function

    def __patch(patchname):

        """patch and updates the files and fuzz variables"""

        fuzz = False

        patcher = util.find_in_path('gpatch', os.environ.get('PATH', ''),

                                    'patch')

        args = []

        if cwd:

            args.append('-d %s' % util.shellquote(cwd))

        fp = os.popen('%s %s -p%d < %s' % (patcher, ' '.join(args), strip,

                                           util.shellquote(patchname)))

        for line in fp:

            line = line.rstrip()

            ui.note(line + '\n')

            if line.startswith('patching file '):

                pf = util.parse_patch_output(line)

                printed_file = False

                files.setdefault(pf, (None, None))

            elif line.find('with fuzz') >= 0:

                fuzz = True

                if not printed_file:

                    ui.warn(pf + '\n')

                    printed_file = True

                ui.warn(line + '\n')

            elif line.find('saving rejects to file') >= 0:

                ui.warn(line + '\n')

            elif line.find('FAILED') >= 0:

                if not printed_file:

                    ui.warn(pf + '\n')

                    printed_file = True

                ui.warn(line + '\n')

        code = fp.close()

        if code:

            raise util.Abort(_("patch command failed: %s") %

                             util.explain_exit(code)[0])

        return fuzz

    (dopatch, gitpatches) = readgitpatch(patchname)

    for gp in gitpatches:

        files[gp.path] = (gp.op, gp)

    fuzz = False

    if dopatch:

        filterpatch = dopatch & (GP_FILTER | GP_BINARY)

        if filterpatch:

            patchname = dogitpatch(patchname, gitpatches, cwd=cwd)

        try:

            if dopatch & GP_PATCH:

                fuzz = __patch(patchname)

        finally:

            if filterpatch:

                os.unlink(patchname)

    return fuzz

def diffopts(ui, opts={}, untrusted=False):

    def get(key, name=None):

        return (opts.get(key) or

                ui.configbool('diff', name or key, None, untrusted=untrusted))

    return mdiff.diffopts(

        text=opts.get('text'),

        git=get('git'),

        nodates=get('nodates'),

        showfunc=get('show_function', 'showfunc'),

        ignorews=get('ignore_all_space', 'ignorews'),

        ignorewsamount=get('ignore_space_change', 'ignorewsamount'),

        ignoreblanklines=get('ignore_blank_lines', 'ignoreblanklines'))

def updatedir(ui, repo, patches, wlock=None):

    '''Update dirstate after patch application according to metadata'''

    if not patches:

        return

    copies = []

    removes = {}

    cfiles = patches.keys()

    cwd = repo.getcwd()

    if cwd:

        cfiles = [util.pathto(repo.root, cwd, f) for f in patches.keys()]

    for f in patches:

        ctype, gp = patches[f]

        if ctype == 'RENAME':

            copies.append((gp.oldpath, gp.path, gp.copymod))

            removes[gp.oldpath] = 1

        elif ctype == 'COPY':

            copies.append((gp.oldpath, gp.path, gp.copymod))

        elif ctype == 'DELETE':

            removes[gp.path] = 1

    for src, dst, after in copies:

        if not after:

            copyfile(src, dst, repo.root)

        repo.copy(src, dst, wlock=wlock)

    removes = removes.keys()

    if removes:

        removes.sort()

        repo.remove(removes, True, wlock=wlock)

    for f in patches:

        ctype, gp = patches[f]

        if gp and gp.mode:

            x = gp.mode & 0100 != 0

            dst = os.path.join(repo.root, gp.path)

            # patch won't create empty files

            if ctype == 'ADD' and not os.path.exists(dst):

                repo.wwrite(gp.path, '', x and 'x' or '')

            else:

                util.set_exec(dst, x)

    cmdutil.addremove(repo, cfiles, wlock=wlock)

    files = patches.keys()

    files.extend([r for r in removes if r not in files])

    files.sort()

    return files

def b85diff(fp, to, tn):

    '''print base85-encoded binary diff'''

    def gitindex(text):

        if not text:

            return '0' * 40

        l = len(text)

        s = sha.new('blob %d\0' % l)

        s.update(text)

        return s.hexdigest()

    def fmtline(line):

        l = len(line)

        if l <= 26:

            l = chr(ord('A') + l - 1)

        else:

            l = chr(l - 26 + ord('a') - 1)

        return '%c%s\n' % (l, base85.b85encode(line, True))

    def chunk(text, csize=52):

        l = len(text)

        i = 0

        while i < l:

            yield text[i:i+csize]

            i += csize

    tohash = gitindex(to)

    tnhash = gitindex(tn)

    if tohash == tnhash:

        return ""

    # TODO: deltas

    ret = ['index %s..%s\nGIT binary patch\nliteral %s\n' %

           (tohash, tnhash, len(tn))]

    for l in chunk(zlib.compress(tn)):

        ret.append(fmtline(l))

    ret.append('\n')

    return ''.join(ret)

def diff(repo, node1=None, node2=None, files=None, match=util.always,

         fp=None, changes=None, opts=None):

    '''print diff of changes to files between two nodes, or node and

    working directory.

    if node1 is None, use first dirstate parent instead.

    if node2 is None, compare node1 with working directory.'''

    if opts is None:

        opts = mdiff.defaultopts

    if fp is None:

        fp = repo.ui

    if not node1:

        node1 = repo.dirstate.parents()[0]

    ccache = {}

    def getctx(r):

        if r not in ccache:

            ccache[r] = context.changectx(repo, r)

        return ccache[r]

    flcache = {}

    def getfilectx(f, ctx):

        flctx = ctx.filectx(f, filelog=flcache.get(f))

        if f not in flcache:

            flcache[f] = flctx._filelog

        return flctx

    # reading the data for node1 early allows it to play nicely

    # with repo.status and the revlog cache.

    ctx1 = context.changectx(repo, node1)

    # force manifest reading

    man1 = ctx1.manifest()

    date1 = util.datestr(ctx1.date())

    if not changes:

        changes = repo.status(node1, node2, files, match=match)[:5]

    modified, added, removed, deleted, unknown = changes

    if not modified and not added and not removed:

        return

    if node2:

        ctx2 = context.changectx(repo, node2)

    else:

        ctx2 = context.workingctx(repo)

    man2 = ctx2.manifest()

    # returns False if there was no rename between ctx1 and ctx2

    # returns None if the file was created between ctx1 and ctx2