# debugcommands.py - command processing for debug* commands
#
# Copyright 2005-2016 Matt Mackall <mpm@selenic.com>
#
# This software may be used and distributed according to the terms of the
# GNU General Public License version 2 or any later version.

from __future__ import absolute_import

import os

from .i18n import _
from .node import (
    hex,
)
from . import (
    cmdutil,
    commands,
    context,
    dagparser,
    error,
    lock as lockmod,
    revlog,
    scmutil,
    simplemerge,
)

release = lockmod.release

# We reuse the command table from commands because it is easier than
# teaching dispatch about multiple tables.
command = cmdutil.command(commands.table)

@command('debugancestor', [], _('[INDEX] REV1 REV2'), optionalrepo=True)
def debugancestor(ui, repo, *args):
    """find the ancestor revision of two revisions in a given index"""
    if len(args) == 3:
        index, rev1, rev2 = args
        r = revlog.revlog(scmutil.opener(os.getcwd(), audit=False), index)
        lookup = r.lookup
    elif len(args) == 2:
        if not repo:
            raise error.Abort(_('there is no Mercurial repository here '
                                '(.hg not found)'))
        rev1, rev2 = args
        r = repo.changelog
        lookup = repo.lookup
    else:
        raise error.Abort(_('either two or three arguments required'))
    a = r.ancestor(lookup(rev1), lookup(rev2))
    ui.write('%d:%s\n' % (r.rev(a), hex(a)))

@command('debugbuilddag',
    [('m', 'mergeable-file', None, _('add single file mergeable changes')),
    ('o', 'overwritten-file', None, _('add single file all revs overwrite')),
    ('n', 'new-file', None, _('add new file at each rev'))],
    _('[OPTION]... [TEXT]'))
def debugbuilddag(ui, repo, text=None,
                  mergeable_file=False,
                  overwritten_file=False,
                  new_file=False):
    """builds a repo with a given DAG from scratch in the current empty repo

    The description of the DAG is read from stdin if not given on the
    command line.

    Elements:

     - "+n" is a linear run of n nodes based on the current default parent
     - "." is a single node based on the current default parent
     - "$" resets the default parent to null (implied at the start);
           otherwise the default parent is always the last node created
     - "<p" sets the default parent to the backref p
     - "*p" is a fork at parent p, which is a backref
     - "*p1/p2" is a merge of parents p1 and p2, which are backrefs
     - "/p2" is a merge of the preceding node and p2
     - ":tag" defines a local tag for the preceding node
     - "@branch" sets the named branch for subsequent nodes
     - "#...\\n" is a comment up to the end of the line

    Whitespace between the above elements is ignored.

    A backref is either

     - a number n, which references the node curr-n, where curr is the current
       node, or
     - the name of a local tag you placed earlier using ":tag", or
     - empty to denote the default parent.

    All string valued-elements are either strictly alphanumeric, or must
    be enclosed in double quotes ("..."), with "\\" as escape character.
    """

    if text is None:
        ui.status(_("reading DAG from stdin\n"))
        text = ui.fin.read()

    cl = repo.changelog
    if len(cl) > 0:
        raise error.Abort(_('repository is not empty'))

    # determine number of revs in DAG
    total = 0
    for type, data in dagparser.parsedag(text):
        if type == 'n':
            total += 1

    if mergeable_file:
        linesperrev = 2
        # make a file with k lines per rev
        initialmergedlines = [str(i) for i in xrange(0, total * linesperrev)]
        initialmergedlines.append("")

    tags = []

    wlock = lock = tr = None
    try:
        wlock = repo.wlock()
        lock = repo.lock()
        tr = repo.transaction("builddag")

        at = -1
        atbranch = 'default'
        nodeids = []
        id = 0
        ui.progress(_('building'), id, unit=_('revisions'), total=total)
        for type, data in dagparser.parsedag(text):
            if type == 'n':
                ui.note(('node %s\n' % str(data)))
                id, ps = data

                files = []
                fctxs = {}

                p2 = None
                if mergeable_file:
                    fn = "mf"
                    p1 = repo[ps[0]]
                    if len(ps) > 1:
                        p2 = repo[ps[1]]
                        pa = p1.ancestor(p2)
                        base, local, other = [x[fn].data() for x in (pa, p1,
                                                                     p2)]
                        m3 = simplemerge.Merge3Text(base, local, other)
                        ml = [l.strip() for l in m3.merge_lines()]
                        ml.append("")
                    elif at > 0:
                        ml = p1[fn].data().split("\n")
                    else:
                        ml = initialmergedlines
                    ml[id * linesperrev] += " r%i" % id
                    mergedtext = "\n".join(ml)
                    files.append(fn)
                    fctxs[fn] = context.memfilectx(repo, fn, mergedtext)

                if overwritten_file:
                    fn = "of"
                    files.append(fn)
                    fctxs[fn] = context.memfilectx(repo, fn, "r%i\n" % id)

                if new_file:
                    fn = "nf%i" % id
                    files.append(fn)
                    fctxs[fn] = context.memfilectx(repo, fn, "r%i\n" % id)
                    if len(ps) > 1:
                        if not p2:
                            p2 = repo[ps[1]]
                        for fn in p2:
                            if fn.startswith("nf"):
                                files.append(fn)
                                fctxs[fn] = p2[fn]

                def fctxfn(repo, cx, path):
                    return fctxs.get(path)

                if len(ps) == 0 or ps[0] < 0:
                    pars = [None, None]
                elif len(ps) == 1:
                    pars = [nodeids[ps[0]], None]
                else:
                    pars = [nodeids[p] for p in ps]
                cx = context.memctx(repo, pars, "r%i" % id, files, fctxfn,
                                    date=(id, 0),
                                    user="debugbuilddag",
                                    extra={'branch': atbranch})
                nodeid = repo.commitctx(cx)
                nodeids.append(nodeid)
                at = id
            elif type == 'l':
                id, name = data
                ui.note(('tag %s\n' % name))
                tags.append("%s %s\n" % (hex(repo.changelog.node(id)), name))
            elif type == 'a':
                ui.note(('branch %s\n' % data))
                atbranch = data
            ui.progress(_('building'), id, unit=_('revisions'), total=total)
        tr.close()

        if tags:
            repo.vfs.write("localtags", "".join(tags))
    finally:
        ui.progress(_('building'), None)
        release(tr, lock, wlock)