#
# Support methods for CD/DVD and ISO image installations.
#
# Copyright 2007 Red Hat, Inc.
#
# This software may be freely redistributed under the terms of the GNU
# library public license.
#
# You should have received a copy of the GNU Library Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
import isys
import os, os.path, stat, string, sys
from constants import *

import rhpl
from rhpl.translate import _

import logging
log = logging.getLogger("anaconda")

# this sucks, but we want to consider s390x as s390x in here but generally
# don't.  *sigh*
if os.uname()[4] == "s390x":
    _arch = "s390x"
else:
    _arch = rhpl.getArch()

def findIsoImages(path, messageWindow):
    flush = os.stat(path)
    files = os.listdir(path)
    arch = _arch
    discImages = {}

    for file in files:
        what = path + '/' + file
        if not isys.isIsoImage(what):
            continue

        try:
            isys.losetup("/dev/loop2", what, readOnly = 1)
        except SystemError:
            continue

        try:
            isys.mount("/dev/loop2", "/mnt/cdimage", fstype = "iso9660",
                       readOnly = 1)
            for num in range(1, 10):
                if os.access("/mnt/cdimage/.discinfo", os.R_OK):
                    f = open("/mnt/cdimage/.discinfo")
                    try:
                        f.readline() # skip timestamp
                        f.readline() # skip release description
                        discArch = string.strip(f.readline()) # read architecture
                        discNum = getDiscNums(f.readline().strip())
                    except:
                        discArch = None
                        discNum = [ 0 ]

                    f.close()

                    if num not in discNum or discArch != arch:
                        continue

                    # if it's disc1, it needs to have images/stage2.img
                    if (num == 1 and not
                        os.access("/mnt/cdimage/images/stage2.img", os.R_OK)):
                        log.warning("%s doesn't have a stage2.img, skipping" %(what,))
                        continue
                    # we only install binary packages, so let's look for a
                    # product/ dir and hope that this avoids getting
                    # discs from the src.rpm set
                    if not os.path.isdir("/mnt/cdimage/%s" %(productPath,)):
                        log.warning("%s doesn't have binary RPMS, skipping" %(what,))
                        continue

                    # warn user if images appears to be wrong size
                    if os.stat(what)[stat.ST_SIZE] % 2048:
                        rc = messageWindow(_("Warning"),
                             _("The ISO image %s has a size which is not "
                               "a multiple of 2048 bytes.  This may mean "
                               "it was corrupted on transfer to this computer."
                               "\n\n"
                               "It is recommended that you exit and abort your "
                               "installation, but you can choose to continue if "
                               "you think this is in error.") % (file,),
                               type="custom", custom_icon="warning",
                               custom_buttons= [_("_Exit installer"),
                                                _("_Continue")])
                        if rc == 0:
                            sys.exit(0)

                    discImages[num] = file

            isys.umount("/mnt/cdimage", removeDir=0)
        except SystemError:
            pass

        isys.unlosetup("/dev/loop2")

    return discImages

def getDiscNums(line):
    # get the disc numbers for this disc
    nums = line.split(",")
    discNums = []
    for num in nums:
        discNums.append(int(num))
    return discNums

def getMediaId(path):
    if os.access("%s/.discinfo" % path, os.R_OK):
        f = open("%s/.discinfo" % path)
        newStamp = f.readline().strip()
        f.close()

        return newStamp
    else:
        return None

# This mounts the directory containing the iso images, and places the
# mount point in isodir.
def mountDirectory(isodir, methodstr, messageWindow):
    if methodstr.startswith("hd://"):
        method = methodstr[5:]
        (device, fstype, path) = method.split(":", 3)
        device = method[0:method.index(":")]
    else:
        return

    # First check to see if isodir is mounted.
    f = open("/proc/mounts", "r")
    lines = f.readlines()
    f.close()

    for l in lines:
        s = string.split(l)
        if s[0] == "/dev/" + device:
            # It is, so there's no need to try again.
            return

    try:
        isys.mount(device, isodir, fstype = fstype)
    except SystemError, msg:
        log.error("couldn't mount ISO source directory: %s" % msg)
        messageWindow(_("Couldn't Mount ISO Source"),
                      _("An error occurred mounting the source "
                        "device %s.  This may happen if your ISO "
                        "images are located on an advanced storage "
                        "device like LVM or RAID, or if there was a "
                        "problem mounting a partition.  Click exit "
                        "to abort the installation.")
                      % (self.device,), type="custom", custom_icon="error",
                      custom_buttons=[_("_Exit")])
        sys.exit(0)

def mountImage(isodir, tree, discnum, messageWindow, discImages={}):
    if os.path.ismount(tree):
        raise SystemError, "trying to mount already-mounted iso image!"

    if discImages == {}:
        discImages = findIsoImages(isodir, messageWindow)

    while True:
        try:
            isoImage = "%s/%s" % (isodir, discImages[discnum])
            isys.losetup("/dev/loop1", isoImage, readOnly = 1)
            isys.mount("/dev/loop1", tree, fstype = 'iso9660', readOnly = 1);
            break
        except:
            ans = messageWindow(_("Missing ISO 9660 Image"),
                                _("The installer has tried to mount "
                                  "image #%s, but cannot find it on "
                                  "the hard drive.\n\n"
                                  "Please copy this image to the "
                                  "drive and click Retry. Click Exit "
                                  " to abort the installation.")
                                  % (discnum,), type="custom",
                                  custom_icon="warning",
                                  custom_buttons=[_("_Exit"), _("_Retry")])
            if ans == 0:
                sys.exit(0)
            elif ans == 1:
                discImages = findIsoImages(isodir, messageWindow)

    return discImages

# given groupset containing information about selected packages, use
# the disc number info in the headers to come up with message describing
# the required CDs
#
# dialog returns a value of 0 if user selected to abort install
def presentRequiredMediaMessage(anaconda):
    reqcds = anaconda.backend.getRequiredMedia()

    # if only one CD required no need to pop up a message
    if len(reqcds) < 2:
        return

    # check what discs our currently mounted one provides
    if os.access("/.discinfo" % anaconda.backend.ayum.tree, os.R_OK):
        discNums = []
        try:
            f = open("%s/.discinfo", anaconda.backend.ayum.tree)
            stamp = f.readline().strip()
            descr = f.readline().strip()
            arch = f.readline().strip()
            discNums = getDiscNums(f.readline().strip())
            f.close()
        except Exception, e:
            log.critical("Exception reading discinfo: %s" %(e,))

        log.info("discNums is %s" %(discNums,))
        haveall = 0
        s = sets.Set(reqcds)
        t = sets.Set(discNums)
        if s.issubset(t):
            haveall = 1

        if haveall == 1:
            return

    reqcds.sort()
    reqcdstr = ""
    for cdnum in reqcds:
        if cdnum == -99: # non-CD bits
            continue
        reqcdstr += "\t\t%s %s disc #%d\n" % (product.productName, product.productVersion, cdnum,)

    return anaconda.intf.messageWindow( _("Required Install Media"),
                                        _("The software you have selected to "
                                          "install will require the following discs:\n\n"
                                          "%s\nPlease "
                                          "have these ready before proceeding with "
                                          "the installation.  If you need to abort "
                                          "the installation and exit please "
                                          "select \"Reboot\".") % (reqcdstr,),
                                          type="custom", custom_icon="warning",
                                          custom_buttons=[_("_Reboot"), _("_Back"), _("_Continue")])

def umountDirectory(self):
    try:
        isys.umount("/tmp/isodir", removeDir=0)
    except:
        pass

def umountImage(tree, currentMedia):
    if currentMedia is not None:
        isys.umount(tree, removeDir=0)
        isys.unlosetup("/dev/loop1")

def unmountCD(path, messageWindow):
    if not path:
        return

    while True:
        try:
            isys.umount(path, removeDir=0)
            break
        except Exception, e:
            log.error("exception in _unmountCD: %s" %(e,))
            messageWindow(_("Error"),
                          _("An error occurred unmounting the disc.  "
                            "Please make sure you're not accessing "
                            "%s from the shell on tty2 "
                            "and then click OK to retry.")
                          % (path,))

def verifyMedia(tree, discnum, timestamp):
    if os.access("%s/.discinfo" % tree, os.R_OK):
        f = open("%s/.discinfo" % tree)

        newStamp = f.readline().strip()

        try:
            descr = f.readline().strip()
        except:
            descr = None

        try:
            arch = f.readline().strip()
        except:
            arch = None

        try:
            discs = getDiscNums(f.readline().strip())
        except:
            discs = [ 0 ]

        f.close()
        if (newStamp == timestamp and arch == _arch and discnum in discs):
            return True

    return False