#!/usr/bin/env python

#

# Minimal support for git commands on an hg repository

#

# Copyright 2005 Chris Mason <mason@suse.com>

#

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

# of the GNU General Public License, incorporated herein by reference.

import time, sys, signal, os

from mercurial import hg, mdiff, fancyopts, commands, ui, util

def dodiff(fp, ui, repo, node1, node2, files=None, match=util.always,

           changes=None, text=False):

    def date(c):

        return time.asctime(time.gmtime(c[2][0]))

    if not changes:

        (c, a, d, u) = repo.changes(node1, node2, files, match=match)

    else:

        (c, a, d, u) = changes

    if files:

        c, a, d = map(lambda x: filterfiles(files, x), (c, a, d))

    if not c and not a and not d:

        return

    if node2:

        change = repo.changelog.read(node2)

        mmap2 = repo.manifest.read(change[0])

        date2 = date(change)

        def read(f):

            return repo.file(f).read(mmap2[f])

    else:

        date2 = time.asctime()

        if not node1:

            node1 = repo.dirstate.parents()[0]

        def read(f):

            return repo.wfile(f).read()

    change = repo.changelog.read(node1)

    mmap = repo.manifest.read(change[0])

    date1 = date(change)

    for f in c:

        to = None

        if f in mmap:

            to = repo.file(f).read(mmap[f])

        tn = read(f)

        fp.write("diff --git a/%s b/%s\n" % (f, f))

        fp.write(mdiff.unidiff(to, date1, tn, date2, f, None, text=text))

    for f in a:

        to = None

        tn = read(f)

        fp.write("diff --git /dev/null b/%s\n" % (f))

        fp.write(mdiff.unidiff(to, date1, tn, date2, f, None, text=text))

    for f in d:

        to = repo.file(f).read(mmap[f])

        tn = None

        fp.write("diff --git a/%s /dev/null\n" % (f))

        fp.write(mdiff.unidiff(to, date1, tn, date2, f, None, text=text))

def difftree(ui, repo, node1=None, node2=None, **opts):

    """diff trees from two commits"""

    def __difftree(repo, node1, node2):

        def date(c):

            return time.asctime(time.gmtime(c[2][0]))

        if node2:

            change = repo.changelog.read(node2)

            mmap2 = repo.manifest.read(change[0])

            (c, a, d, u) = repo.changes(node1, node2)

            def read(f): return repo.file(f).read(mmap2[f])

            date2 = date(change)

        else:

            date2 = time.asctime()

            (c, a, d, u) = repo.changes(node1, None)

            if not node1:

                node1 = repo.dirstate.parents()[0]

            def read(f): return file(os.path.join(repo.root, f)).read()

        change = repo.changelog.read(node1)

        mmap = repo.manifest.read(change[0])

        date1 = date(change)

        empty = "0" * 40;

        for f in c:

            # TODO get file permissions

            print ":100664 100664 %s %s M\t%s\t%s" % (hg.hex(mmap[f]),

                                                      hg.hex(mmap2[f]), f, f)

        for f in a:

            print ":000000 100664 %s %s N\t%s\t%s" % (empty, hg.hex(mmap2[f]), f, f)

        for f in d:

            print ":100664 000000 %s %s D\t%s\t%s" % (hg.hex(mmap[f]), empty, f, f)

    ##

    while True:

        if opts['stdin']:

            try:

                line = raw_input().split(' ')

                node1 = line[0]

                if len(line) > 1:

                    node2 = line[1]

                else:

                    node2 = None

            except EOFError:

                break

        node1 = repo.lookup(node1)

        if node2:

            node2 = repo.lookup(node2)

        else:

            node2 = node1

            node1 = repo.changelog.parents(node1)[0]

        if opts['patch']:

            if opts['pretty']:

                catcommit(repo, node2, "")

            dodiff(sys.stdout, ui, repo, node1, node2)

        else:

            __difftree(repo, node1, node2)

        if not opts['stdin']:

            break

def catcommit(repo, n, prefix, changes=None):

    nlprefix = '\n' + prefix;

    (p1, p2) = repo.changelog.parents(n)

    (h, h1, h2) = map(hg.hex, (n, p1, p2))

    (i1, i2) = map(repo.changelog.rev, (p1, p2))

    if not changes:

        changes = repo.changelog.read(n)

    print "tree %s" % (hg.hex(changes[0]))

    if i1 != -1: print "parent %s" % (h1)

    if i2 != -1: print "parent %s" % (h2)

    date_ar = changes[2]

    date = int(float(date_ar[0]))

    lines = changes[4].splitlines()

    if lines[-1].startswith('committer:'):

        committer = lines[-1].split(': ')[1].rstrip()

    else:

        committer = "%s %s %s" % (changes[1], date, date_ar[1])

    print "author %s %s %s" % (changes[1], date, date_ar[1])

    print "committer %s" % (committer)

    print ""

    if prefix != "":

        print "%s%s" % (prefix, changes[4].replace('\n', nlprefix).strip())

    else:

        print changes[4]

    if prefix:

        sys.stdout.write('\0')

def base(ui, repo, node1, node2):

    """Output common ancestor information"""

    node1 = repo.lookup(node1)

    node2 = repo.lookup(node2)

    n = repo.changelog.ancestor(node1, node2)

    print hg.hex(n)

def catfile(ui, repo, type=None, r=None, **opts):

    """cat a specific revision"""

    # in stdin mode, every line except the commit is prefixed with two

    # spaces.  This way the our caller can find the commit without magic

    # strings

    #

    prefix = ""

    if opts['stdin']:

        try:

            (type, r) = raw_input().split(' ');

            prefix = "    "

        except EOFError:

            return

    else:

        if not type or not r:

            ui.warn("cat-file: type or revision not supplied\n")

            commands.help_(ui, 'cat-file')

    while r:

        if type != "commit":

            sys.stderr.write("aborting hg cat-file only understands commits\n")

            sys.exit(1);

        n = repo.lookup(r)

        catcommit(repo, n, prefix)

        if opts['stdin']:

            try:

                (type, r) = raw_input().split(' ');

            except EOFError:

                break

        else:

            break

# git rev-tree is a confusing thing.  You can supply a number of

# commit sha1s on the command line, and it walks the commit history

# telling you which commits are reachable from the supplied ones via

# a bitmask based on arg position.

# you can specify a commit to stop at by starting the sha1 with ^

def revtree(args, repo, full="tree", maxnr=0, parents=False):

    def chlogwalk():

        ch = repo.changelog

        count = ch.count()

        i = count

        l = [0] * 100

        chunk = 100

        while True:

            if chunk > i:

                chunk = i

                i = 0

            else:

                i -= chunk

            for x in xrange(0, chunk):

                if i + x >= count:

                    l[chunk - x:] = [0] * (chunk - x)

                    break

                if full != None:

                    l[x] = ch.read(ch.node(i + x))

                else:

                    l[x] = 1

            for x in xrange(chunk-1, -1, -1):

                if l[x] != 0:

                    yield (i + x, full != None and l[x] or None)

            if i == 0:

                break

    # calculate and return the reachability bitmask for sha

    def is_reachable(ar, reachable, sha):

        if len(ar) == 0:

            return 1

        mask = 0

        for i in range(len(ar)):

            if sha in reachable[i]:

                mask |= 1 << i

        return mask

    reachable = []

    stop_sha1 = []

    want_sha1 = []

    count = 0

    # figure out which commits they are asking for and which ones they

    # want us to stop on

    for i in range(len(args)):

        if args[i].startswith('^'):

            s = repo.lookup(args[i][1:])

            stop_sha1.append(s)

            want_sha1.append(s)

        elif args[i] != 'HEAD':

            want_sha1.append(repo.lookup(args[i]))

    # calculate the graph for the supplied commits

    for i in range(len(want_sha1)):

        reachable.append({});

        n = want_sha1[i];

        visit = [n];

        reachable[i][n] = 1

        while visit:

            n = visit.pop(0)

            if n in stop_sha1:

                continue

            for p in repo.changelog.parents(n):

                if p not in reachable[i]:

                    reachable[i][p] = 1

                    visit.append(p)

                if p in stop_sha1:

                    continue

    # walk the repository looking for commits that are in our

    # reachability graph

    #for i in range(repo.changelog.count()-1, -1, -1):

    for i, changes in chlogwalk():

        n = repo.changelog.node(i)

        mask = is_reachable(want_sha1, reachable, n)

        if mask:

            parentstr = ""

            if parents:

                pp = repo.changelog.parents(n)

                if pp[0] != hg.nullid:

                    parentstr += " " + hg.hex(pp[0])

                if pp[1] != hg.nullid:

                    parentstr += " " + hg.hex(pp[1])

            if not full:

                print hg.hex(n) + parentstr

            elif full is "commit":

                print hg.hex(n) + parentstr

                catcommit(repo, n, '    ', changes)

            else:

                (p1, p2) = repo.changelog.parents(n)

                (h, h1, h2) = map(hg.hex, (n, p1, p2))

                (i1, i2) = map(repo.changelog.rev, (p1, p2))

                date = changes[2][0]

                print "%s %s:%s" % (date, h, mask),

                mask = is_reachable(want_sha1, reachable, p1)

                if i1 != -1 and mask > 0:

                    print "%s:%s " % (h1, mask),

                mask = is_reachable(want_sha1, reachable, p2)

                if i2 != -1 and mask > 0:

                    print "%s:%s " % (h2, mask),

                print ""

            if maxnr and count >= maxnr:

                break

            count += 1

# git rev-list tries to order things by date, and has the ability to stop

# at a given commit without walking the whole repo.  TODO add the stop

# parameter

def revlist(ui, repo, *revs, **opts):

    """print revisions"""

    if opts['header']:

        full = "commit"

    else:

        full = None

    copy = [x for x in revs]

    revtree(copy, repo, full, opts['max_count'], opts['parents'])

def view(ui, repo, *etc):

    "start interactive history viewer"

    os.chdir(repo.root)

    os.system(ui.config("hgk", "path", "hgk") + " " + " ".join(etc))

cmdtable = {

    "view": (view, [], 'hg view'),

    "debug-diff-tree": (difftree, [('p', 'patch', None, 'generate patch'),

                            ('r', 'recursive', None, 'recursive'),

                            ('P', 'pretty', None, 'pretty'),

                            ('s', 'stdin', None, 'stdin'),

                            ('C', 'copy', None, 'detect copies'),

                            ('S', 'search', "", 'search')],

                            "hg git-diff-tree [options] node1 node2"),

    "debug-cat-file": (catfile, [('s', 'stdin', None, 'stdin')],

                 "hg debug-cat-file [options] type file"),

    "debug-merge-base": (base, [], "hg debug-merge-base node node"),

    "debug-rev-list": (revlist, [('H', 'header', None, 'header'),

                           ('t', 'topo-order', None, 'topo-order'),

                           ('p', 'parents', None, 'parents'),

                           ('n', 'max-count', 0, 'max-count')],

                 "hg debug-rev-list [options] revs"),

}

def reposetup(ui, repo):

    pass