# convert.py Foreign SCM converter
#
# 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, incorporated herein by reference.

from common import NoRepo, SKIPREV, converter_source, converter_sink, mapfile
from cvs import convert_cvs
from darcs import darcs_source
from git import convert_git
from hg import mercurial_source, mercurial_sink
from subversion import debugsvnlog, svn_source, svn_sink
import filemap

import os, shutil
from mercurial import hg, ui, util, commands
from mercurial.i18n import _

commands.norepo += " convert debugsvnlog"

source_converters = [
    ('cvs', convert_cvs),
    ('git', convert_git),
    ('svn', svn_source),
    ('hg', mercurial_source),
    ('darcs', darcs_source),
    ]

sink_converters = [
    ('hg', mercurial_sink),
    ('svn', svn_sink),
    ]

def convertsource(ui, path, type, rev):
    exceptions = []
    for name, source in source_converters:
        try:
            if not type or name == type:
                return source(ui, path, rev)
        except NoRepo, inst:
            exceptions.append(inst)
    if not ui.quiet:
        for inst in exceptions:
            ui.write(_("%s\n") % inst)
    raise util.Abort('%s: unknown repository type' % path)

def convertsink(ui, path, type):
    for name, sink in sink_converters:
        try:
            if not type or name == type:
                return sink(ui, path)
        except NoRepo, inst:
            ui.note(_("convert: %s\n") % inst)
    raise util.Abort('%s: unknown repository type' % path)

class converter(object):
    def __init__(self, ui, source, dest, revmapfile, opts):

        self.source = source
        self.dest = dest
        self.ui = ui
        self.opts = opts
        self.commitcache = {}
        self.authors = {}
        self.authorfile = None

        self.map = mapfile(ui, revmapfile)

        # Read first the dst author map if any
        authorfile = self.dest.authorfile()
        if authorfile and os.path.exists(authorfile):
            self.readauthormap(authorfile)
        # Extend/Override with new author map if necessary
        if opts.get('authors'):
            self.readauthormap(opts.get('authors'))
            self.authorfile = self.dest.authorfile()

    def walktree(self, heads):
        '''Return a mapping that identifies the uncommitted parents of every
        uncommitted changeset.'''
        visit = heads
        known = {}
        parents = {}
        while visit:
            n = visit.pop(0)
            if n in known or n in self.map: continue
            known[n] = 1
            commit = self.cachecommit(n)
            parents[n] = []
            for p in commit.parents:
                parents[n].append(p)
                visit.append(p)

        return parents

    def toposort(self, parents):
        '''Return an ordering such that every uncommitted changeset is
        preceeded by all its uncommitted ancestors.'''
        visit = parents.keys()
        seen = {}
        children = {}

        while visit:
            n = visit.pop(0)
            if n in seen: continue
            seen[n] = 1
            # Ensure that nodes without parents are present in the 'children'
            # mapping.
            children.setdefault(n, [])
            for p in parents[n]:
                if not p in self.map:
                    visit.append(p)
                children.setdefault(p, []).append(n)

        s = []
        removed = {}
        visit = children.keys()
        while visit:
            n = visit.pop(0)
            if n in removed: continue
            dep = 0
            if n in parents:
                for p in parents[n]:
                    if p in self.map: continue
                    if p not in removed:
                        # we're still dependent
                        visit.append(n)
                        dep = 1
                        break

            if not dep:
                # all n's parents are in the list
                removed[n] = 1
                if n not in self.map:
                    s.append(n)
                if n in children:
                    for c in children[n]:
                        visit.insert(0, c)

        if self.opts.get('datesort'):
            depth = {}
            for n in s:
                depth[n] = 0
                pl = [p for p in self.commitcache[n].parents
                      if p not in self.map]
                if pl:
                    depth[n] = max([depth[p] for p in pl]) + 1

            s = [(depth[n], self.commitcache[n].date, n) for n in s]
            s.sort()
            s = [e[2] for e in s]

        return s

    def writeauthormap(self):
        authorfile = self.authorfile
        if authorfile:
           self.ui.status('Writing author map file %s\n' % authorfile)
           ofile = open(authorfile, 'w+')
           for author in self.authors:
               ofile.write("%s=%s\n" % (author, self.authors[author]))
           ofile.close()

    def readauthormap(self, authorfile):
        afile = open(authorfile, 'r')
        for line in afile:
            try:
                srcauthor = line.split('=')[0].strip()
                dstauthor = line.split('=')[1].strip()
                if srcauthor in self.authors and dstauthor != self.authors[srcauthor]:
                    self.ui.status(
                        'Overriding mapping for author %s, was %s, will be %s\n'
                        % (srcauthor, self.authors[srcauthor], dstauthor))
                else:
                    self.ui.debug('Mapping author %s to %s\n'
                                  % (srcauthor, dstauthor))
                    self.authors[srcauthor] = dstauthor
            except IndexError:
                self.ui.warn(
                    'Ignoring bad line in author file map %s: %s\n'
                    % (authorfile, line))
        afile.close()

    def cachecommit(self, rev):
        commit = self.source.getcommit(rev)
        commit.author = self.authors.get(commit.author, commit.author)
        self.commitcache[rev] = commit
        return commit

    def copy(self, rev):
        commit = self.commitcache[rev]
        do_copies = hasattr(self.dest, 'copyfile')
        filenames = []

        changes = self.source.getchanges(rev)
        if isinstance(changes, basestring):
            if changes == SKIPREV:
                dest = SKIPREV
            else:
                dest = self.map[changes]
            self.map[rev] = dest
            return
        files, copies = changes
        parents = [self.map[r] for r in commit.parents]
        if commit.parents:
            prev = commit.parents[0]
            if prev not in self.commitcache:
                self.cachecommit(prev)
            pbranch = self.commitcache[prev].branch
        else:
            pbranch = None
        self.dest.setbranch(commit.branch, pbranch, parents)
        for f, v in files:
            filenames.append(f)
            try:
                data = self.source.getfile(f, v)
            except IOError, inst:
                self.dest.delfile(f)
            else:
                e = self.source.getmode(f, v)
                self.dest.putfile(f, e, data)
                if do_copies:
                    if f in copies:
                        copyf = copies[f]
                        # Merely marks that a copy happened.
                        self.dest.copyfile(copyf, f)

        newnode = self.dest.putcommit(filenames, parents, commit)
        self.source.converted(rev, newnode)
        self.map[rev] = newnode

    def convert(self):
        try:
            self.source.before()
            self.dest.before()
            self.source.setrevmap(self.map)
            self.ui.status("scanning source...\n")
            heads = self.source.getheads()
            parents = self.walktree(heads)
            self.ui.status("sorting...\n")
            t = self.toposort(parents)
            num = len(t)
            c = None

            self.ui.status("converting...\n")
            for c in t:
                num -= 1
                desc = self.commitcache[c].desc
                if "\n" in desc:
                    desc = desc.splitlines()[0]
                self.ui.status("%d %s\n" % (num, desc))
                self.copy(c)

            tags = self.source.gettags()
            ctags = {}
            for k in tags:
                v = tags[k]
                if self.map.get(v, SKIPREV) != SKIPREV:
                    ctags[k] = self.map[v]

            if c and ctags:
                nrev = self.dest.puttags(ctags)
                # write another hash correspondence to override the previous
                # one so we don't end up with extra tag heads
                if nrev:
                    self.map[c] = nrev

            self.writeauthormap()
        finally:
            self.cleanup()

    def cleanup(self):
        try:
            self.dest.after()
        finally:
            self.source.after()
        self.map.close()

def convert(ui, src, dest=None, revmapfile=None, **opts):
    """Convert a foreign SCM repository to a Mercurial one.

    Accepted source formats:
    - Mercurial
    - CVS
    - Darcs
    - git
    - Subversion

    Accepted destination formats:
    - Mercurial
    - Subversion (history on branches is not preserved)

    If no revision is given, all revisions will be converted. Otherwise,
    convert will only import up to the named revision (given in a format
    understood by the source).

    If no destination directory name is specified, it defaults to the
    basename of the source with '-hg' appended.  If the destination
    repository doesn't exist, it will be created.

    If <MAPFILE> isn't given, it will be put in a default location
    (<dest>/.hg/shamap by default).  The <MAPFILE> is a simple text
    file that maps each source commit ID to the destination ID for
    that revision, like so:
    <source ID> <destination ID>

    If the file doesn't exist, it's automatically created.  It's updated
    on each commit copied, so convert-repo can be interrupted and can
    be run repeatedly to copy new commits.

    The [username mapping] file is a simple text file that maps each source
    commit author to a destination commit author. It is handy for source SCMs
    that use unix logins to identify authors (eg: CVS). One line per author
    mapping and the line format is:
    srcauthor=whatever string you want

    The filemap is a file that allows filtering and remapping of files
    and directories.  Comment lines start with '#'.  Each line can
    contain one of the following directives:

      include path/to/file

      exclude path/to/file

      rename from/file to/file
    
    The 'include' directive causes a file, or all files under a
    directory, to be included in the destination repository, and the
    exclusion of all other files and dirs not explicitely included.
    The 'exclude' directive causes files or directories to be omitted.
    The 'rename' directive renames a file or directory.  To rename from a
    subdirectory into the root of the repository, use '.' as the path to
    rename to.

    Back end options:

    --config convert.hg.clonebranches=False   (boolean)
        hg target: XXX not documented
    --config convert.hg.saverev=True          (boolean)
        hg source: allow target to preserve source revision ID
    --config convert.hg.tagsbranch=default    (branch name)
        hg target: XXX not documented
    --config convert.hg.usebranchnames=True   (boolean)
        hg target: preserve branch names

    --config convert.svn.branches=branches    (directory name)
        svn source: specify the directory containing branches
    --config convert.svn.tags=tags            (directory name)
        svn source: specify the directory containing tags
    --config convert.svn.trunk=trunk          (directory name)
        svn source: specify the name of the trunk branch
    """

    util._encoding = 'UTF-8'

    if not dest:
        dest = hg.defaultdest(src) + "-hg"
        ui.status("assuming destination %s\n" % dest)

    destc = convertsink(ui, dest, opts.get('dest_type'))

    try:
        srcc = convertsource(ui, src, opts.get('source_type'),
                             opts.get('rev'))
    except Exception:
        for path in destc.created:
            shutil.rmtree(path, True)
        raise

    fmap = opts.get('filemap')
    if fmap:
        srcc = filemap.filemap_source(ui, srcc, fmap)
        destc.setfilemapmode(True)

    if not revmapfile:
        try:
            revmapfile = destc.revmapfile()
        except:
            revmapfile = os.path.join(destc, "map")

    c = converter(ui, srcc, destc, revmapfile, opts)
    c.convert()


cmdtable = {
    "convert":
        (convert,
         [('A', 'authors', '', 'username mapping filename'),
          ('d', 'dest-type', '', 'destination repository type'),
          ('', 'filemap', '', 'remap file names using contents of file'),
          ('r', 'rev', '', 'import up to target revision REV'),
          ('s', 'source-type', '', 'source repository type'),
          ('', 'datesort', None, 'try to sort changesets by date')],
         'hg convert [OPTION]... SOURCE [DEST [MAPFILE]]'),
    "debugsvnlog":
        (debugsvnlog,
         [],
         'hg debugsvnlog'),
}