#!/usr/bin/python
#
# makeupdates - Generate an updates.img containing changes since the last
#               tag, but only changes that do not need to be compiled.  If
#               you need an updated _isys.so or a new loader, you should
#               still compile things as usual.
#
# Copyright (C) 2009  Red Hat, Inc.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU Lesser General Public License as published
# by the Free Software Foundation; either version 2.1 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Author: David Cantrell <dcantrell@redhat.com>

import getopt
import os
import shutil
import subprocess
import sys

def getArchiveTag(configure, spec):
    tag = ""

    f = open(configure)
    lines = f.readlines()
    f.close()

    for line in lines:
        if line.startswith('AC_INIT('):
            fields = line.split('[')
            tag += fields[1].split(']')[0] + '-' + fields[2].split(']')[0]
            break
        else:
            continue

    f = open(spec)
    lines = f.readlines()
    f.close()

    for line in lines:
        if line.startswith('Release:'):
            tag += '-' + line.split()[1].split('%')[0]
        else:
            continue

    return tag

def getArchiveTagOffset(configure, spec, offset):
    tag = getArchiveTag(configure, spec)

    if not tag.count("-") >= 2:
        return tag
    ldash = tag.rfind("-")
    bldash = tag[:ldash].rfind("-")
    ver = tag[bldash+1:ldash]

    if not ver.count(".") >= 1:
        return tag
    ver = ver[:ver.rfind(".")]

    if not len(ver) > 0:
        return tag
    globstr = "refs/tags/" + tag[:bldash+1] + ver + ".*"
    proc = subprocess.Popen(['git', 'for-each-ref', '--sort=taggerdate',
                             '--format=%(tag)', globstr],
                            stdout=subprocess.PIPE,
                            stderr=subprocess.PIPE).communicate()
    lines = proc[0].strip("\n").split('\n')
    lines.reverse()

    try:
        return lines[offset]
    except IndexError:
        return tag

def doGitDiff(tag, args=[]):
    proc = subprocess.Popen(['git', 'diff', '--name-status', tag] + args,
                            stdout=subprocess.PIPE,
                            stderr=subprocess.PIPE).communicate()

    lines = proc[0].split('\n')
    return lines

def copyUpdatedFiles(tag, updates, cwd):
    def pruneFile(src, names):
        lst = []

        for name in names:
            if name.startswith('Makefile') or name.endswith('.pyc'):
                lst.append(name)

        return lst

    subdirs = []

    lines = doGitDiff(tag)
    for line in lines:
        fields = line.split()

        if len(fields) < 2:
            continue

        status = fields[0]
        file = fields[1]

        if status == "D":
            continue

        if file.endswith('.spec.in') or (file.find('Makefile') != -1) or \
           file.endswith('.c') or file.endswith('.h') or \
           file.endswith('.sh') or file == 'configure.ac':
            continue

        if file.find('/') != -1:
            fields = file.split('/')
            subdir = fields[0]

            if subdir == 'installclasses' or subdir == 'storage' or \
               subdir == 'booty':
                subupdates = os.path.realpath(updates + '/' + subdir)
                if os.path.isdir(subupdates):
                    shutil.rmtree(subupdates)

                if not subdir in subdirs:
                    sys.stdout.write("Including %s/\n" % (subdir,))
                    subdirs.append(subdir)

                shutil.copytree(os.path.realpath(cwd + '/' + subdir),
                                subupdates, ignore=pruneFile)
            elif subdir == 'loader' or subdir == 'po' or \
                 subdir =='scripts' or subdir == 'command-stubs' or \
                 subdir == 'tests' or subdir == 'bootdisk' or \
                 subdir == 'docs' or subdir == 'fonts' or \
                 subdir == 'utils' or subdir == 'gptsync' or \
                 subdir == 'liveinst':
                continue
            else:
                sys.stdout.write("Including %s\n" % (file,))
                shutil.copy2(file, updates)
        else:
            sys.stdout.write("Including %s\n" % (file,))
            shutil.copy2(file, updates)

def isysChanged(tag):
    lines = doGitDiff(tag, ['isys'])

    for line in lines:
        fields = line.split()

        if len(fields) < 2:
            continue

        status = fields[0]
        file = fields[1]

        if status == "D":
            continue

        if file.startswith('Makefile') or file.endswith('.h') or \
           file.endswith('.c'):
            return True

    return False

def copyUpdatedIsys(updates, cwd):
    os.chdir(cwd)

    if not os.path.isfile('Makefile'):
        if not os.path.isfile('configure'):
            os.system('./autogen.sh')
        os.system('./configure')

    os.system('make')

    isysmodule = os.path.realpath(cwd + '/isys/.libs/_isys.so')
    if os.path.isfile(isysmodule):
        shutil.copy2(isysmodule, updates)

def createUpdatesImage(cwd, updates):
    os.chdir(updates)
    os.system("find . | cpio -c -o | gzip -9cv > %s/updates.img" % (cwd,))
    sys.stdout.write("updates.img ready\n")

def usage(cmd):
    sys.stdout.write("Usage: %s [OPTION]...\n" % (cmd,))
    sys.stdout.write("Options:\n")
    sys.stdout.write("    -k, --keep       Do not delete updates subdirectory.\n")
    sys.stdout.write("    -c, --compile    Compile code if there are isys changes.\n")
    sys.stdout.write("    -h, --help       Display this help and exit.\n")
    sys.stdout.write("    -t, --tag        Make image from TAG to HEAD.\n")
    sys.stdout.write("    -o, --offset     Make image from (latest_tag - OFFSET) to HEAD.\n")

def main(argv):
    prog = os.path.basename(sys.argv[0])
    cwd = os.getcwd()
    configure = os.path.realpath(cwd + '/configure.ac')
    spec = os.path.realpath(cwd + '/anaconda.spec.in')
    updates = cwd + '/updates'
    keep, compile, help, unknown = False, False, False, False
    tag = None
    opts = []
    offset = 0

    try:
        opts, args = getopt.getopt(sys.argv[1:], 't:o:kc?',
                                   ['tag=', 'offset=',
                                    'keep', 'compile', 'help'])
    except getopt.GetoptError:
        help = True

    for o, a in opts:
        if o in ('-k', '--keep'):
            keep = True
        elif o in ('-c', '--compile'):
            compile = True
        elif o in ('-?', '--help'):
            help = True
        elif o in ('-t', '--tag'):
            tag = a
        elif o in ('-o', '--offset'):
            offset = int(a)
        else:
            unknown = True

    if help:
        usage(prog)
        sys.exit(0)
    elif unknown:
        sys.stderr.write("%s: extra operand `%s'" % (prog, sys.argv[1],))
        sys.stderr.write("Try `%s --help' for more information." % (prog,))
        sys.exit(1)

    if not os.path.isfile(configure) and not os.path.isfile(spec):
        sys.stderr.write("You must be at the top level of the anaconda source tree.\n")
        sys.exit(1)

    if not tag:
        if offset < 1:
            tag = getArchiveTag(configure, spec)
        else:
            tag = getArchiveTagOffset(configure, spec, offset)
        sys.stdout.write("Using tag: %s\n" % tag)

    if not os.path.isdir(updates):
        os.makedirs(updates)

    copyUpdatedFiles(tag, updates, cwd)

    if compile:
        if isysChanged(tag):
            copyUpdatedIsys(updates, cwd)

    createUpdatesImage(cwd, updates)

    if not keep:
        shutil.rmtree(updates)

if __name__ == "__main__":
    main(sys.argv)