# Copyright 2009-2010 Gregory P. Ward
# Copyright 2009-2010 Intelerad Medical Systems Incorporated
# Copyright 2010-2011 Fog Creek Software
# Copyright 2010-2011 Unity Technologies
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

'''setup for largefiles repositories: reposetup'''
import copy
import types
import os

from mercurial import context, error, manifest, match as match_, util
from mercurial import node as node_
from mercurial.i18n import _

import lfcommands
import proto
import lfutil

def reposetup(ui, repo):
    # wire repositories should be given new wireproto functions but not the
    # other largefiles modifications
    if not repo.local():
        return proto.wirereposetup(ui, repo)

    for name in ('status', 'commitctx', 'commit', 'push'):
        method = getattr(repo, name)
        if (isinstance(method, types.FunctionType) and
            method.func_name == 'wrap'):
            ui.warn(_('largefiles: repo method %r appears to have already been'
                    ' wrapped by another extension: '
                    'largefiles may behave incorrectly\n')
                    % name)

    class lfilesrepo(repo.__class__):
        lfstatus = False
        def status_nolfiles(self, *args, **kwargs):
            return super(lfilesrepo, self).status(*args, **kwargs)

        # When lfstatus is set, return a context that gives the names
        # of largefiles instead of their corresponding standins and
        # identifies the largefiles as always binary, regardless of
        # their actual contents.
        def __getitem__(self, changeid):
            ctx = super(lfilesrepo, self).__getitem__(changeid)
            if self.lfstatus:
                class lfilesmanifestdict(manifest.manifestdict):
                    def __contains__(self, filename):
                        if super(lfilesmanifestdict,
                                self).__contains__(filename):
                            return True
                        return super(lfilesmanifestdict,
                            self).__contains__(lfutil.standin(filename))
                class lfilesctx(ctx.__class__):
                    def files(self):
                        filenames = super(lfilesctx, self).files()
                        return [lfutil.splitstandin(f) or f for f in filenames]
                    def manifest(self):
                        man1 = super(lfilesctx, self).manifest()
                        man1.__class__ = lfilesmanifestdict
                        return man1
                    def filectx(self, path, fileid=None, filelog=None):
                        try:
                            if filelog is not None:
                                result = super(lfilesctx, self).filectx(
                                    path, fileid, filelog)
                            else:
                                result = super(lfilesctx, self).filectx(
                                    path, fileid)
                        except error.LookupError:
                            # Adding a null character will cause Mercurial to
                            # identify this as a binary file.
                            if filelog is not None:
                                result = super(lfilesctx, self).filectx(
                                    lfutil.standin(path), fileid, filelog)
                            else:
                                result = super(lfilesctx, self).filectx(
                                    lfutil.standin(path), fileid)
                            olddata = result.data
                            result.data = lambda: olddata() + '\0'
                        return result
                ctx.__class__ = lfilesctx
            return ctx

        # Figure out the status of big files and insert them into the
        # appropriate list in the result. Also removes standin files
        # from the listing. Revert to the original status if
        # self.lfstatus is False.
        def status(self, node1='.', node2=None, match=None, ignored=False,
                clean=False, unknown=False, listsubrepos=False):
            listignored, listclean, listunknown = ignored, clean, unknown
            if not self.lfstatus:
                return super(lfilesrepo, self).status(node1, node2, match,
                    listignored, listclean, listunknown, listsubrepos)
            else:
                # some calls in this function rely on the old version of status
                self.lfstatus = False
                if isinstance(node1, context.changectx):
                    ctx1 = node1
                else:
                    ctx1 = repo[node1]
                if isinstance(node2, context.changectx):
                    ctx2 = node2
                else:
                    ctx2 = repo[node2]
                working = ctx2.rev() is None
                parentworking = working and ctx1 == self['.']

                def inctx(file, ctx):
                    try:
                        if ctx.rev() is None:
                            return file in ctx.manifest()
                        ctx[file]
                        return True
                    except KeyError:
                        return False

                if match is None:
                    match = match_.always(self.root, self.getcwd())

                # First check if there were files specified on the
                # command line.  If there were, and none of them were
                # largefiles, we should just bail here and let super
                # handle it -- thus gaining a big performance boost.
                lfdirstate = lfutil.openlfdirstate(ui, self)
                if match.files() and not match.anypats():
                    for f in lfdirstate:
                        if match(f):
                            break
                    else:
                        return super(lfilesrepo, self).status(node1, node2,
                                match, listignored, listclean,
                                listunknown, listsubrepos)

                # Create a copy of match that matches standins instead
                # of largefiles.
                def tostandins(files):
                    if not working:
                        return files
                    newfiles = []
                    dirstate = repo.dirstate
                    for f in files:
                        sf = lfutil.standin(f)
                        if sf in dirstate:
                            newfiles.append(sf)
                        elif sf in dirstate.dirs():
                            # Directory entries could be regular or
                            # standin, check both
                            newfiles.extend((f, sf))
                        else:
                            newfiles.append(f)
                    return newfiles

                # Create a function that we can use to override what is
                # normally the ignore matcher.  We've already checked
                # for ignored files on the first dirstate walk, and
                # unecessarily re-checking here causes a huge performance
                # hit because lfdirstate only knows about largefiles
                def _ignoreoverride(self):
                    return False

                m = copy.copy(match)
                m._files = tostandins(m._files)

                # Get ignored files here even if we weren't asked for them; we
                # must use the result here for filtering later
                result = super(lfilesrepo, self).status(node1, node2, m,
                    True, clean, unknown, listsubrepos)
                if working:
                    try:
                        # Any non-largefiles that were explicitly listed must be
                        # taken out or lfdirstate.status will report an error.
                        # The status of these files was already computed using
                        # super's status.
                        # Override lfdirstate's ignore matcher to not do
                        # anything
                        origignore = lfdirstate._ignore
                        lfdirstate._ignore = _ignoreoverride

                        def sfindirstate(f):
                            sf = lfutil.standin(f)
                            dirstate = repo.dirstate
                            return sf in dirstate or sf in dirstate.dirs()
                        match._files = [f for f in match._files
                                        if sfindirstate(f)]
                        # Don't waste time getting the ignored and unknown
                        # files again; we already have them
                        s = lfdirstate.status(match, [], False,
                                listclean, False)
                        (unsure, modified, added, removed, missing, unknown,
                                ignored, clean) = s
                        # Replace the list of ignored and unknown files with
                        # the previously caclulated lists, and strip out the
                        # largefiles
                        lfiles = set(lfdirstate._map)
                        ignored = set(result[5]).difference(lfiles)
                        unknown = set(result[4]).difference(lfiles)
                        if parentworking:
                            for lfile in unsure:
                                standin = lfutil.standin(lfile)
                                if standin not in ctx1:
                                    # from second parent
                                    modified.append(lfile)
                                elif ctx1[standin].data().strip() \
                                        != lfutil.hashfile(self.wjoin(lfile)):
                                    modified.append(lfile)
                                else:
                                    clean.append(lfile)
                                    lfdirstate.normal(lfile)
                        else:
                            tocheck = unsure + modified + added + clean
                            modified, added, clean = [], [], []

                            for lfile in tocheck:
                                standin = lfutil.standin(lfile)
                                if inctx(standin, ctx1):
                                    if ctx1[standin].data().strip() != \
                                            lfutil.hashfile(self.wjoin(lfile)):
                                        modified.append(lfile)
                                    else:
                                        clean.append(lfile)
                                else:
                                    added.append(lfile)
                    finally:
                        # Replace the original ignore function
                        lfdirstate._ignore = origignore

                    for standin in ctx1.manifest():
                        if not lfutil.isstandin(standin):
                            continue
                        lfile = lfutil.splitstandin(standin)
                        if not match(lfile):
                            continue
                        if lfile not in lfdirstate:
                            removed.append(lfile)

                    # Filter result lists
                    result = list(result)

                    # Largefiles are not really removed when they're
                    # still in the normal dirstate. Likewise, normal
                    # files are not really removed if it's still in
                    # lfdirstate. This happens in merges where files
                    # change type.
                    removed = [f for f in removed if f not in repo.dirstate]
                    result[2] = [f for f in result[2] if f not in lfdirstate]

                    # Unknown files
                    unknown = set(unknown).difference(ignored)
                    result[4] = [f for f in unknown
                                 if (repo.dirstate[f] == '?' and
                                     not lfutil.isstandin(f))]
                    # Ignored files were calculated earlier by the dirstate,
                    # and we already stripped out the largefiles from the list
                    result[5] = ignored
                    # combine normal files and largefiles
                    normals = [[fn for fn in filelist
                                if not lfutil.isstandin(fn)]
                               for filelist in result]
                    lfiles = (modified, added, removed, missing, [], [], clean)
                    result = [sorted(list1 + list2)
                              for (list1, list2) in zip(normals, lfiles)]
                else:
                    def toname(f):
                        if lfutil.isstandin(f):
                            return lfutil.splitstandin(f)
                        return f
                    result = [[toname(f) for f in items] for items in result]

                if not listunknown:
                    result[4] = []
                if not listignored:
                    result[5] = []
                if not listclean:
                    result[6] = []
                self.lfstatus = True
                return result

        # As part of committing, copy all of the largefiles into the
        # cache.
        def commitctx(self, *args, **kwargs):
            node = super(lfilesrepo, self).commitctx(*args, **kwargs)
            lfutil.copyalltostore(self, node)
            return node

        # Before commit, largefile standins have not had their
        # contents updated to reflect the hash of their largefile.
        # Do that here.
        def commit(self, text="", user=None, date=None, match=None,
                force=False, editor=False, extra={}):
            orig = super(lfilesrepo, self).commit

            wlock = repo.wlock()
            try:
                # Case 0: Rebase or Transplant
                # We have to take the time to pull down the new largefiles now.
                # Otherwise, any largefiles that were modified in the
                # destination changesets get overwritten, either by the rebase
                # or in the first commit after the rebase or transplant.
                # updatelfiles will update the dirstate to mark any pulled
                # largefiles as modified
                if getattr(repo, "_isrebasing", False) or \
                        getattr(repo, "_istransplanting", False):
                    lfcommands.updatelfiles(repo.ui, repo, filelist=None,
                                            printmessage=False)
                    result = orig(text=text, user=user, date=date, match=match,
                                    force=force, editor=editor, extra=extra)
                    return result
                # Case 1: user calls commit with no specific files or
                # include/exclude patterns: refresh and commit all files that
                # are "dirty".
                if ((match is None) or
                    (not match.anypats() and not match.files())):
                    # Spend a bit of time here to get a list of files we know
                    # are modified so we can compare only against those.
                    # It can cost a lot of time (several seconds)
                    # otherwise to update all standins if the largefiles are
                    # large.
                    lfdirstate = lfutil.openlfdirstate(ui, self)
                    dirtymatch = match_.always(repo.root, repo.getcwd())
                    s = lfdirstate.status(dirtymatch, [], False, False, False)
                    modifiedfiles = []
                    for i in s:
                        modifiedfiles.extend(i)
                    lfiles = lfutil.listlfiles(self)
                    # this only loops through largefiles that exist (not
                    # removed/renamed)
                    for lfile in lfiles:
                        if lfile in modifiedfiles:
                            if os.path.exists(
                                    self.wjoin(lfutil.standin(lfile))):
                                # this handles the case where a rebase is being
                                # performed and the working copy is not updated
                                # yet.
                                if os.path.exists(self.wjoin(lfile)):
                                    lfutil.updatestandin(self,
                                        lfutil.standin(lfile))
                                    lfdirstate.normal(lfile)
                    for lfile in lfdirstate:
                        if lfile in modifiedfiles:
                            if not os.path.exists(
                                    repo.wjoin(lfutil.standin(lfile))):
                                lfdirstate.drop(lfile)

                    result = orig(text=text, user=user, date=date, match=match,
                                    force=force, editor=editor, extra=extra)
                    # This needs to be after commit; otherwise precommit hooks
                    # get the wrong status
                    lfdirstate.write()
                    return result

                for f in match.files():
                    if lfutil.isstandin(f):
                        raise util.Abort(
                            _('file "%s" is a largefile standin') % f,
                            hint=('commit the largefile itself instead'))

                # Case 2: user calls commit with specified patterns: refresh
                # any matching big files.
                smatcher = lfutil.composestandinmatcher(self, match)
                standins = lfutil.dirstatewalk(self.dirstate, smatcher)

                # No matching big files: get out of the way and pass control to
                # the usual commit() method.
                if not standins:
                    return orig(text=text, user=user, date=date, match=match,
                                    force=force, editor=editor, extra=extra)

                # Refresh all matching big files.  It's possible that the
                # commit will end up failing, in which case the big files will
                # stay refreshed.  No harm done: the user modified them and
                # asked to commit them, so sooner or later we're going to
                # refresh the standins.  Might as well leave them refreshed.
                lfdirstate = lfutil.openlfdirstate(ui, self)
                for standin in standins:
                    lfile = lfutil.splitstandin(standin)
                    if lfdirstate[lfile] <> 'r':
                        lfutil.updatestandin(self, standin)
                        lfdirstate.normal(lfile)
                    else:
                        lfdirstate.drop(lfile)

                # Cook up a new matcher that only matches regular files or
                # standins corresponding to the big files requested by the
                # user.  Have to modify _files to prevent commit() from
                # complaining "not tracked" for big files.
                lfiles = lfutil.listlfiles(repo)
                match = copy.copy(match)
                origmatchfn = match.matchfn

                # Check both the list of largefiles and the list of
                # standins because if a largefile was removed, it
                # won't be in the list of largefiles at this point
                match._files += sorted(standins)

                actualfiles = []
                for f in match._files:
                    fstandin = lfutil.standin(f)

                    # ignore known largefiles and standins
                    if f in lfiles or fstandin in standins:
                        continue

                    # append directory separator to avoid collisions
                    if not fstandin.endswith(os.sep):
                        fstandin += os.sep

                    actualfiles.append(f)
                match._files = actualfiles

                def matchfn(f):
                    if origmatchfn(f):
                        return f not in lfiles
                    else:
                        return f in standins

                match.matchfn = matchfn
                result = orig(text=text, user=user, date=date, match=match,
                                force=force, editor=editor, extra=extra)
                # This needs to be after commit; otherwise precommit hooks
                # get the wrong status
                lfdirstate.write()
                return result
            finally:
                wlock.release()

        def push(self, remote, force=False, revs=None, newbranch=False):
            o = lfutil.findoutgoing(repo, remote, force)
            if o:
                toupload = set()
                o = repo.changelog.nodesbetween(o, revs)[0]
                for n in o:
                    parents = [p for p in repo.changelog.parents(n)
                               if p != node_.nullid]
                    ctx = repo[n]
                    files = set(ctx.files())
                    if len(parents) == 2:
                        mc = ctx.manifest()
                        mp1 = ctx.parents()[0].manifest()
                        mp2 = ctx.parents()[1].manifest()
                        for f in mp1:
                            if f not in mc:
                                files.add(f)
                        for f in mp2:
                            if f not in mc:
                                files.add(f)
                        for f in mc:
                            if mc[f] != mp1.get(f, None) or mc[f] != mp2.get(f,
                                    None):
                                files.add(f)

                    toupload = toupload.union(
                        set([ctx[f].data().strip()
                             for f in files
                             if lfutil.isstandin(f) and f in ctx]))
                lfcommands.uploadlfiles(ui, self, remote, toupload)
            return super(lfilesrepo, self).push(remote, force, revs,
                newbranch)

    repo.__class__ = lfilesrepo

    def checkrequireslfiles(ui, repo, **kwargs):
        if 'largefiles' not in repo.requirements and util.any(
                lfutil.shortname+'/' in f[0] for f in repo.store.datafiles()):
            repo.requirements.add('largefiles')
            repo._writerequirements()

    ui.setconfig('hooks', 'changegroup.lfiles', checkrequireslfiles)
    ui.setconfig('hooks', 'commit.lfiles', checkrequireslfiles)
