# extdiff.py - external diff program support for mercurial

#

# Copyright 2006 Vadim Gelfer <vadim.gelfer@gmail.com>

#

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

# GNU General Public License version 2, incorporated herein by reference.

'''command to allow external programs to compare revisions

  [extdiff]

  # add new command that runs GNU diff(1) in 'context diff' mode

  cdiff = gdiff -Nprc5

  ## or the old way:

  #cmd.cdiff = gdiff

  #opts.cdiff = -Nprc5

  # add new command called vdiff, runs kdiff3

  vdiff = kdiff3

  # add new command called meld, runs meld (no need to name twice)

  meld =

  vimdiff = gvim -f '+next' '+execute "DirDiff" argv(0) argv(1)'

'''

from mercurial.i18n import _

from mercurial.node import short

from mercurial import cmdutil, util, commands

import os, shlex, shutil, tempfile

def snapshot(ui, repo, files, node, tmproot):

    '''snapshot files as of some revision

    if not using snapshot, -I/-X does not work and recursive diff

    in tools like kdiff3 and meld displays too many files.'''

    dirname = os.path.basename(repo.root)

    if dirname == "":

        dirname = "root"

    if node is not None:

        dirname = '%s.%s' % (dirname, short(node))

    base = os.path.join(tmproot, dirname)

    os.mkdir(base)

    if node is not None:

        ui.note(_('making snapshot of %d files from rev %s\n') %

                (len(files), short(node)))

    else:

        ui.note(_('making snapshot of %d files from working directory\n') %

            (len(files)))

    wopener = util.opener(base)

    fns_and_mtime = []

    ctx = repo[node]

    for fn in files:

        wfn = util.pconvert(fn)

        if not wfn in ctx:

            # skipping new file after a merge ?

            continue

        ui.note('  %s\n' % wfn)

        dest = os.path.join(base, wfn)

        fctx = ctx[wfn]

        data = repo.wwritedata(wfn, fctx.data())

        if 'l' in fctx.flags():

            wopener.symlink(data, wfn)

        else:

            wopener(wfn, 'w').write(data)

            if 'x' in fctx.flags():

                util.set_flags(dest, False, True)

        if node is None:

            fns_and_mtime.append((dest, repo.wjoin(fn), os.path.getmtime(dest)))

    return dirname, fns_and_mtime

def dodiff(ui, repo, diffcmd, diffopts, pats, opts):

    '''Do the actuall diff:

    - copy to a temp structure if diffing 2 internal revisions

    - copy to a temp structure if diffing working revision with

      another one and more than 1 file is changed

    - just invoke the diff for a single file in the working dir

    '''

    revs = opts.get('rev')

    change = opts.get('change')

    if revs and change:

        msg = _('cannot specify --rev and --change at the same time')

        raise util.Abort(msg)

    elif change:

        node2 = repo.lookup(change)

        node1 = repo[node2].parents()[0].node()

    else:

        node1, node2 = cmdutil.revpair(repo, revs)

    matcher = cmdutil.match(repo, pats, opts)

    modified, added, removed = repo.status(node1, node2, matcher)[:3]

    if not (modified or added or removed):

        return 0

    tmproot = tempfile.mkdtemp(prefix='extdiff.')

    dir2root = ''

    try:

        # Always make a copy of node1

        dir1 = snapshot(ui, repo, modified + removed, node1, tmproot)[0]

        changes = len(modified) + len(removed) + len(added)

        # If node2 in not the wc or there is >1 change, copy it

        if node2 or changes > 1:

            dir2, fns_and_mtime = snapshot(ui, repo, modified + added, node2, tmproot)

        else:

            # This lets the diff tool open the changed file directly

            dir2 = ''

            dir2root = repo.root

            fns_and_mtime = []

        # If only one change, diff the files instead of the directories

        if changes == 1 :

            if len(modified):

                dir1 = os.path.join(dir1, util.localpath(modified[0]))

                dir2 = os.path.join(dir2root, dir2, util.localpath(modified[0]))

            elif len(removed) :

                dir1 = os.path.join(dir1, util.localpath(removed[0]))

                dir2 = os.devnull

            else:

                dir1 = os.devnull

                dir2 = os.path.join(dir2root, dir2, util.localpath(added[0]))

        cmdline = ('%s %s %s %s' %

                   (util.shellquote(diffcmd), ' '.join(diffopts),

                    util.shellquote(dir1), util.shellquote(dir2)))

        ui.debug(_('running %r in %s\n') % (cmdline, tmproot))

        util.system(cmdline, cwd=tmproot)

        for copy_fn, working_fn, mtime in fns_and_mtime:

            if os.path.getmtime(copy_fn) != mtime:

                ui.debug(_('file changed while diffing. '

                         'Overwriting: %s (src: %s)\n') % (working_fn, copy_fn))

                util.copyfile(copy_fn, working_fn)

        return 1

    finally:

        ui.note(_('cleaning up temp directory\n'))

        shutil.rmtree(tmproot)

def extdiff(ui, repo, *pats, **opts):

    '''use external program to diff repository (or selected files)

    program = opts['program'] or 'diff'

    if opts['program']:

        option = opts['option']

    else:

        option = opts['option'] or ['-Npru']

    return dodiff(ui, repo, program, option, pats, opts)

cmdtable = {

    "extdiff":

    (extdiff,

     [('p', 'program', '', _('comparison program to run')),

      ('o', 'option', [], _('pass option to comparison program')),

      ('r', 'rev', [], _('revision')),

      ('c', 'change', '', _('change made by revision')),

     ] + commands.walkopts,

     _('hg extdiff [OPT]... [FILE]...')),

    }

def uisetup(ui):

    for cmd, path in ui.configitems('extdiff'):

        if cmd.startswith('cmd.'):

            cmd = cmd[4:]

            if not path: path = cmd

            diffopts = ui.config('extdiff', 'opts.' + cmd, '')

            diffopts = diffopts and [diffopts] or []

        elif cmd.startswith('opts.'):

            continue

        else:

            # command = path opts

            if path:

                diffopts = shlex.split(path)

                path = diffopts.pop(0)

            else:

                path, diffopts = cmd, []

        def save(cmd, path, diffopts):

            '''use closure to save diff command to use'''

            def mydiff(ui, repo, *pats, **opts):

                return dodiff(ui, repo, path, diffopts, pats, opts)

            mydiff.__doc__ = _('''\

use %(path)s to diff repository (or selected files)

    Show differences between revisions for the specified files, using the

    %(path)s program.

    When two revision arguments are given, then changes are shown between

    those revisions. If only one revision is specified then that revision is

    compared to the working directory, and, when no revisions are specified,

    the working directory files are compared to its parent.\

''') % dict(path=util.uirepr(path))

            return mydiff

        cmdtable[cmd] = (save(cmd, path, diffopts),

                         cmdtable['extdiff'][1][1:],

                         _('hg %s [OPTION]... [FILE]...') % cmd)