# Module dedicated to host new commands added by the evolve extensions
#
# Copyright 2017 Octobus <contact@octobus.net>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

# Status: Stabilization of the API in progress
#
#   The final set of command should go into core.
#
#   Some command still live in evolve/__init__.py

from __future__ import absolute_import

from mercurial import (
    cmdutil,
    commands,
    context,
    copies,
    error,
    lock as lockmod,
    node,
    obsolete,
    phases,
    scmutil,
    util,
)

from mercurial.i18n import _

from . import (
    exthelper,
)

eh = exthelper.exthelper()

walkopts = commands.walkopts
commitopts = commands.commitopts
commitopts2 = commands.commitopts2
mergetoolopts = commands.mergetoolopts

# option added by evolve

def _resolveoptions(ui, opts):
    """modify commit options dict to handle related options

    For now, all it does is figure out the commit date: respect -D unless
    -d was supplied.
    """
    # N.B. this is extremely similar to setupheaderopts() in mq.py
    if not opts.get('date') and opts.get('current_date'):
        opts['date'] = '%d %d' % util.makedate()
    if not opts.get('user') and opts.get('current_user'):
        opts['user'] = ui.username()

commitopts3 = [
    ('D', 'current-date', None,
     _('record the current date as commit date')),
    ('U', 'current-user', None,
     _('record the current user as committer')),
]

interactiveopt = [['i', 'interactive', None, _('use interactive mode')]]

def _bookmarksupdater(repo, oldid, tr):
    """Return a callable update(newid) updating the current bookmark
    and bookmarks bound to oldid to newid.
    """
    def updatebookmarks(newid):
        dirty = False
        oldbookmarks = repo.nodebookmarks(oldid)
        if oldbookmarks:
            for b in oldbookmarks:
                repo._bookmarks[b] = newid
            dirty = True
        if dirty:
            repo._bookmarks.recordchange(tr)
    return updatebookmarks

@eh.command(
    'amend|refresh',
    [('A', 'addremove', None,
      _('mark new/missing files as added/removed before committing')),
     ('e', 'edit', False, _('invoke editor on commit messages')),
     ('', 'close-branch', None,
      _('mark a branch as closed, hiding it from the branch list')),
     ('s', 'secret', None, _('use the secret phase for committing')),
    ] + walkopts + commitopts + commitopts2 + commitopts3 + interactiveopt,
    _('[OPTION]... [FILE]...'))
def amend(ui, repo, *pats, **opts):
    """combine a changeset with updates and replace it with a new one

    Commits a new changeset incorporating both the changes to the given files
    and all the changes from the current parent changeset into the repository.

    See :hg:`commit` for details about committing changes.

    If you don't specify -m, the parent's message will be reused.

    Returns 0 on success, 1 if nothing changed.
    """
    opts = opts.copy()
    edit = opts.pop('edit', False)
    log = opts.get('logfile')
    opts['amend'] = True
    if not (edit or opts['message'] or log):
        opts['message'] = repo['.'].description()
    _resolveoptions(ui, opts)
    _alias, commitcmd = cmdutil.findcmd('commit', commands.table)
    return commitcmd[0](ui, repo, *pats, **opts)

def _touchedbetween(repo, source, dest, match=None):
    touched = set()
    for files in repo.status(source, dest, match=match)[:3]:
        touched.update(files)
    return touched

def _commitfiltered(repo, ctx, match, target=None, message=None):
    """Recommit ctx with changed files not in match. Return the new
    node identifier, or None if nothing changed.
    """
    base = ctx.p1()
    if target is None:
        target = base
    # ctx
    initialfiles = _touchedbetween(repo, base, ctx)
    if base == target:
        affected = set(f for f in initialfiles if match(f))
        newcontent = set()
    else:
        affected = _touchedbetween(repo, target, ctx, match=match)
        newcontent = _touchedbetween(repo, target, base, match=match)
    # The commit touchs all existing files
    # + all file that needs a new content
    # - the file affected bny uncommit with the same content than base.
    files = (initialfiles - affected) | newcontent
    if not newcontent and files == initialfiles:
        return None

    # Filter copies
    copied = copies.pathcopies(target, ctx)
    copied = dict((dst, src) for dst, src in copied.iteritems()
                  if dst in files)

    def filectxfn(repo, memctx, path, contentctx=ctx, redirect=newcontent):
        if path in redirect:
            return filectxfn(repo, memctx, path, contentctx=target, redirect=())
        if path not in contentctx:
            return None
        fctx = contentctx[path]
        flags = fctx.flags()
        mctx = context.memfilectx(repo, fctx.path(), fctx.data(),
                                  islink='l' in flags,
                                  isexec='x' in flags,
                                  copied=copied.get(path))
        return mctx

    if message is None:
        message = ctx.description()
    new = context.memctx(repo,
                         parents=[base.node(), node.nullid],
                         text=message,
                         files=files,
                         filectxfn=filectxfn,
                         user=ctx.user(),
                         date=ctx.date(),
                         extra=ctx.extra())
    # commitctx always create a new revision, no need to check
    newid = repo.commitctx(new)
    return newid

def _uncommitdirstate(repo, oldctx, match):
    """Fix the dirstate after switching the working directory from
    oldctx to a copy of oldctx not containing changed files matched by
    match.
    """
    ctx = repo['.']
    ds = repo.dirstate
    copies = dict(ds.copies())
    m, a, r = repo.status(oldctx.p1(), oldctx, match=match)[:3]
    for f in m:
        if ds[f] == 'r':
            # modified + removed -> removed
            continue
        ds.normallookup(f)

    for f in a:
        if ds[f] == 'r':
            # added + removed -> unknown
            ds.drop(f)
        elif ds[f] != 'a':
            ds.add(f)

    for f in r:
        if ds[f] == 'a':
            # removed + added -> normal
            ds.normallookup(f)
        elif ds[f] != 'r':
            ds.remove(f)

    # Merge old parent and old working dir copies
    oldcopies = {}
    for f in (m + a):
        src = oldctx[f].renamed()
        if src:
            oldcopies[f] = src[0]
    oldcopies.update(copies)
    copies = dict((dst, oldcopies.get(src, src))
                  for dst, src in oldcopies.iteritems())
    # Adjust the dirstate copies
    for dst, src in copies.iteritems():
        if (src not in ctx or dst in ctx or ds[dst] != 'a'):
            src = None
        ds.copy(src, dst)

@eh.command(
    '^uncommit',
    [('a', 'all', None, _('uncommit all changes when no arguments given')),
     ('r', 'rev', '', _('revert commit content to REV instead')),
     ] + commands.walkopts + commitopts,
    _('[OPTION]... [NAME]'))
def uncommit(ui, repo, *pats, **opts):
    """move changes from parent revision to working directory

    Changes to selected files in the checked out revision appear again as
    uncommitted changed in the working directory. A new revision
    without the selected changes is created, becomes the checked out
    revision, and obsoletes the previous one.

    The --include option specifies patterns to uncommit.
    The --exclude option specifies patterns to keep in the commit.

    The --rev argument let you change the commit file to a content of another
    revision. It still does not change the content of your file in the working
    directory.

    Return 0 if changed files are uncommitted.
    """

    wlock = lock = tr = None
    try:
        wlock = repo.wlock()
        lock = repo.lock()
        wctx = repo[None]
        if len(wctx.parents()) <= 0:
            raise error.Abort(_("cannot uncommit null changeset"))
        if len(wctx.parents()) > 1:
            raise error.Abort(_("cannot uncommit while merging"))
        old = repo['.']
        if old.phase() == phases.public:
            raise error.Abort(_("cannot rewrite immutable changeset"))
        if len(old.parents()) > 1:
            raise error.Abort(_("cannot uncommit merge changeset"))
        oldphase = old.phase()

        rev = None
        if opts.get('rev'):
            rev = scmutil.revsingle(repo, opts.get('rev'))
            ctx = repo[None]
            if ctx.p1() == rev or ctx.p2() == rev:
                raise error.Abort(_("cannot uncommit to parent changeset"))

        onahead = old.rev() in repo.changelog.headrevs()
        disallowunstable = not obsolete.isenabled(repo,
                                                  obsolete.allowunstableopt)
        if disallowunstable and not onahead:
            raise error.Abort(_("cannot uncommit in the middle of a stack"))

        # Recommit the filtered changeset
        tr = repo.transaction('uncommit')
        updatebookmarks = _bookmarksupdater(repo, old.node(), tr)
        newid = None
        includeorexclude = opts.get('include') or opts.get('exclude')
        if (pats or includeorexclude or opts.get('all')):
            match = scmutil.match(old, pats, opts)
            if not (opts['message'] or opts['logfile']):
                opts['message'] = old.description()
            message = cmdutil.logmessage(ui, opts)
            newid = _commitfiltered(repo, old, match, target=rev,
                                    message=message)
        if newid is None:
            raise error.Abort(_('nothing to uncommit'),
                              hint=_("use --all to uncommit all files"))
        # Move local changes on filtered changeset
        obsolete.createmarkers(repo, [(old, (repo[newid],))])
        phases.retractboundary(repo, tr, oldphase, [newid])
        with repo.dirstate.parentchange():
            repo.dirstate.setparents(newid, node.nullid)
            _uncommitdirstate(repo, old, match)
        updatebookmarks(newid)
        if not repo[newid].files():
            ui.warn(_("new changeset is empty\n"))
            ui.status(_("(use 'hg prune .' to remove it)\n"))
        tr.close()
    finally:
        lockmod.release(tr, lock, wlock)