#
# platform.py:  Architecture-specific information
#
# Copyright (C) 2009
# Red Hat, Inc.  All rights reserved.
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 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 General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.
#
# Authors: Chris Lumens <clumens@redhat.com>
#

import iutil
import parted
import storage
from flags import flags
from storage.errors import *
from storage.formats import *
from storage.partspec import *

import gettext
_ = lambda x: gettext.ldgettext("anaconda", x)
N_ = lambda x: x

class Platform(object):
    """Platform

       A class containing platform-specific information and methods for use
       during installation.  The intent is to eventually encapsulate all the
       architecture quirks in one place to avoid lots of platform checks
       throughout anaconda."""
    _bootFSTypes = ["ext3"]
    _disklabel_types = ["msdos"]
    _isEfi = iutil.isEfi()
    _minimumSector = 0
    _packages = []
    _excluded_packages = []
    _supportsLvmBoot = False
    _supportsMdRaidBoot = False
    _minBootPartSize = 50
    _maxBootPartSize = 0

    def __init__(self, anaconda):
        """Creates a new Platform object.  This is basically an abstract class.
           You should instead use one of the platform-specific classes as
           returned by getPlatform below.  Not all subclasses need to provide
           all the methods in this class."""
        self.anaconda = anaconda

    def _mntDict(self):
        """Return a dictionary mapping mount points to devices."""
        ret = {}
        for device in [d for d in self.anaconda.id.storage.devices if d.format.mountable]:
            ret[device.format.mountpoint] = device

        return ret

    def bootDevice(self):
        """Return the device where /boot is mounted."""
        if self.__class__ is Platform:
            raise NotImplementedError("bootDevice not implemented for this platform")

        mntDict = self._mntDict()
        return mntDict.get("/boot", mntDict.get("/"))

    @property
    def defaultBootFSType(self):
        """Return the default filesystem type for the boot partition."""
        return self._bootFSTypes[0]

    @property
    def bootFSTypes(self):
        """Return a list of all valid filesystem types for the boot partition."""
        return self._bootFSTypes

    def bootloaderChoices(self, bl):
        """Return the default list of places to install the bootloader.
           This is returned as a dictionary of locations to (device, identifier)
           tuples.  If there is no boot device, an empty dictionary is
           returned."""
        if self.__class__ is Platform:
            raise NotImplementedError("bootloaderChoices not implemented for this platform")

        bootDev = self.bootDevice()
        ret = {}

        if not bootDev:
            return ret

        if bootDev.type == "mdarray":
            ret["boot"] = (bootDev.name, N_("RAID Device"))
            ret["mbr"] = (bl.drivelist[0], N_("Master Boot Record (MBR)"))
        else:
            ret["boot"] = (bootDev.name, N_("First sector of boot partition"))
            ret["mbr"] = (bl.drivelist[0], N_("Master Boot Record (MBR)"))

        return ret

    def checkBootRequest(self, req):
        """Perform an architecture-specific check on the boot device.  Not all
           platforms may need to do any checks.  Returns a list of errors if
           there is a problem, or [] otherwise."""
        errors = []

        if not req:
            return [_("You have not created a bootable partition.")]

        # most arches can't have boot on a logical volume
        if req.type == "lvmlv" and not self.supportsLvmBoot:
            errors.append(_("Bootable partitions cannot be on a logical volume."))

        # most arches can't have boot on RAID
        if req.type == "mdarray":
            if not self.supportsMdRaidBoot:
                errors.append(_("Bootable partitions cannot be on a RAID device."))
            elif req.level != 1:
                errors.append(_("Bootable partitions can only be on RAID1 devices."))

        # Make sure /boot is on a supported FS type.  This prevents crazy
        # things like boot on vfat.
        if not req.format.bootable or \
           (getattr(req.format, "mountpoint", None) == "/boot" and
            req.format.type not in self.bootFSTypes):
            errors.append(_("Bootable partitions cannot be on an %s filesystem.") % req.format.type)

        if req.type == "luks/dm-crypt":
            # Handle encrypted boot on a partition.
            errors.append(_("Bootable partitions cannot be on an encrypted block device"))
        else:
            # Handle encrypted boot on more complicated devices.
            for dev in filter(lambda d: d.type == "luks/dm-crypt", self.anaconda.id.storage.devices):
                if req in self.anaconda.id.storage.deviceDeps(dev):
                    errors.append(_("Bootable partitions cannot be on an encrypted block device"))

        return errors

    @property
    def diskLabelTypes(self):
        """A list of valid disklabel types for this architecture."""
        return self._disklabel_types

    @property
    def defaultDiskLabelType(self):
        """The default disklabel type for this architecture."""
        return self.diskLabelTypes[0]

    def requiredDiskLabelType(self, device_type):
        return None

    def bestDiskLabelType(self, device):
        """The best disklabel type for the specified device."""
        # if there's a required type for this device type, use that
        labelType = self.requiredDiskLabelType(device.partedDevice.type)
        log.debug("required disklabel type for %s (%s) is %s"
                  % (device.name, device.partedDevice.type, labelType))
        if not labelType:
            # otherwise, use the first supported type for this platform
            # that is large enough to address the whole device
            labelType = self.defaultDiskLabelType
            log.debug("default disklabel type for %s is %s" % (device.name,
                                                               labelType))
            for lt in self.diskLabelTypes:
                l = parted.freshDisk(device=device.partedDevice, ty=lt)
                if l.maxPartitionStartSector > device.partedDevice.length:
                    labelType = lt
                    log.debug("selecting %s disklabel for %s based on size"
                              % (labelType, device.name))
                    break

        return labelType

    @property
    def isEfi(self):
        return self._isEfi

    @property
    def minimumSector(self, disk):
        """Return the minimum starting sector for the provided disk."""
        return self._minimumSector

    @property
    def packages (self):
        if self.anaconda.isKickstart and self.anaconda.id.ksdata.bootloader.disabled:
            packages = []
        else:
            packages = self._packages

        if flags.cmdline.get('fips', None) == '1':
            packages += ['dracut-fips']
        return packages

    @property
    def excluded_packages (self):
        if flags.cmdline.get('fips', None) == '1':
            return self._excluded_packages + ['prelink']
        return self._excluded_packages

    def setDefaultPartitioning(self):
        """Return the default platform-specific partitioning information."""
        return [PartSpec(mountpoint="/boot", fstype=self.defaultBootFSType, size=500,
                         weight=self.weight(mountpoint="/boot"))]

    @property
    def supportsLvmBoot(self):
        """Does the platform support /boot on LVM logical volume?"""
        return self._supportsLvmBoot

    @property
    def supportsMdRaidBoot(self):
        """Does the platform support /boot on MD RAID?"""
        return self._supportsMdRaidBoot

    @property
    def minBootPartSize(self):
        return self._minBootPartSize

    @property
    def maxBootPartSize(self):
        return self._maxBootPartSize

    def validBootPartSize(self, size):
        """ Is the given size (in MB) acceptable for a boot device? """
        if not isinstance(size, int) and not isinstance(size, float):
            return False

        return ((not self.minBootPartSize or size >= self.minBootPartSize)
                and
                (not self.maxBootPartSize or size <= self.maxBootPartSize))

    def weight(self, fstype=None, mountpoint=None):
        """ Given an fstype (as a string) or a mountpoint, return an integer
            for the base sorting weight.  This is used to modify the sort
            algorithm for partition requests, mainly to make sure bootable
            partitions and /boot are placed where they need to be."""
        if mountpoint and mountpoint == "/boot":
            return 2000
        else:
            return 0

class EFI(Platform):
    _bootFSTypes = ["ext4", "ext3", "ext2"]
    _disklabel_types = ["gpt"]
    _minBootPartSize = 50

    def bootDevice(self):
        """
        Return the boot device. The bootloader.drivelist is used to
        set the precedence in cases where multiple partitions are
        available from multiple devices.

        Return the first ESP with a mountpoint, if there is one.
        Otherwise, return the first ESP.

        bootDevice() is called in a number of contexts, and the strategy
        above is supposed to be the best for all.

        A boot device with a mountpoint set is always preferred, as it
        is assumed that that mountpoint will be valid to boot from,
        and that it was set deliberately by some sort of user intervention.

        Only a subset of the contexts in which bootDevice() can be called
        require that the device's mountpoint be set for it to be useful.
        During sanity checking, which occurs shortly before execution of
        scheduled actions on storage, there are some conditions under which
        the mountpoint must be set to prevent failure when storage
        actions are executed.
        """
        drive = self.anaconda.id.bootloader.drivelist[0]

        def _isESP(part):
            return part.disk and \
               part.disk.name == drive and \
               part.format.type == "efi" and \
               self.validBootPartSize(part.size)
        esps = (p for p in self.anaconda.id.storage.partitions if _isESP(p))

        bootDevice = None
        for part in esps:
            if part.format.mountpoint:
                bootDevice = part
                break
            bootDevice = bootDevice or part
        return bootDevice

    def bootloaderChoices(self, bl):
        bootDev = self.bootDevice()
        ret = {}

        if not bootDev:
            return ret

        ret["boot"] = (bootDev.name, N_("EFI System Partition"))
        return ret

    def checkBootRequest(self, req):
        """ Perform architecture-specific checks on the boot device.

            Returns a list of error strings.

            NOTE: X86 does not have a separate checkBootRequest method,
                  so this one must work for x86 as well as EFI.
        """
        if self.isEfi and (not req or not req.format.mountpoint):
            return [_("You have not created a /boot/efi partition.")]
        elif not req:
            return [_("You have not created a bootable partition.")]

        # Get the /boot device, which will be different from req on EFI
        mntDict = self._mntDict()
        boot_device = mntDict.get("/boot", mntDict.get("/"))

        errors = Platform.checkBootRequest(self, req)

        if req.format.mountpoint == "/boot/efi":
            if req.format.type != "efi":
                errors.append(_("/boot/efi is not EFI."))

            # EFI also needs /boot to be on an extX partition, either as its own
            # partition or with / on extX. Get the format of whatever /boot is on
            boot_errors = Platform.checkBootRequest(self, boot_device)
            errors += boot_errors

        if not boot_device:
            return errors

        # Limit /boot to 2TB
        if boot_device.size > 2*1024*1024:
            # If there is no /boot, ask for one
            if boot_device.format.mountpoint == "/":
                errors.append(_("/boot must be less than 2TB. Shrink / or create a separate /boot partition."))
            else:
                errors.append(_("/boot must be less than 2TB"))

        # Don't try to check the disklabel on lv's etc.
        partitions = []
        if req.type == "partition":
            partitions = [ req ]
        elif req.type == "mdarray":
            partitions = filter(lambda d: d.type == "partition", req.parents)

        # Check that we've got a correct disk label.
        for p in partitions:
            partedDisk = p.disk.format.partedDisk
            labelType = self.defaultDiskLabelType
            # Allow using gpt with x86, but not msdos with EFI
            if partedDisk.type != labelType and partedDisk.type != "gpt":
                errors.append(_("%s must have a %s disk label.")
                              % (p.disk.name, labelType.upper()))

        return errors

    def setDefaultPartitioning(self):
        ret = Platform.setDefaultPartitioning(self)
        ret.append(PartSpec(mountpoint="/boot/efi", fstype="efi", size=self._minBootPartSize,
                            maxSize=200, grow=True, weight=self.weight(fstype="efi")))
        return ret

    def weight(self, fstype=None, mountpoint=None):
        if fstype and fstype == "efi" or mountpoint and mountpoint == "/boot/efi":
            return 5000
        elif mountpoint and mountpoint == "/boot":
            return 2000
        else:
            return 0

class Alpha(Platform):
    _disklabel_types = ["bsd"]

    def checkBootRequest(self, req):
        errors = Platform.checkBootRequest(self, req)

        if not req or req.type != "partition" or not req.disk:
            return errors

        disk = req.disk.format.partedDisk

        # Check that we're a BSD disk label
        if not disk.type in self.diskLabelTypes:
            errors.append(_("%s must have a bsd disk label.") % req.disk.name)

        # The first free space should start at the beginning of the drive and
        # span for a megabyte or more.
        free = disk.getFirstPartition()
        while free:
            if free.type & parted.PARTITION_FREESPACE:
                break

            free = free.nextPartition()

        if not free or free.geoemtry.start != 1L or free.getSize(unit="MB") < 1:
            errors.append(_("The disk %s requires at least 1MB of free space at the beginning.") % req.disk.name)

        return errors

class IA64(EFI):
    _packages = ["elilo"]

    def __init__(self, anaconda):
        EFI.__init__(self, anaconda)

class PPC(Platform):
    _bootFSTypes = ["ext4", "ext3", "ext2"]
    _packages = ["yaboot"]
    _ppcMachine = iutil.getPPCMachine()
    _supportsMdRaidBoot = True

    @property
    def ppcMachine(self):
        return self._ppcMachine

    def checkBootRequest(self, req):
        errors = Platform.checkBootRequest(self, req)

        if req != self.bootDevice():
            # yaboot cannot find /boot on a logical partition
            if hasattr(req, "partedPartition") and req.isLogical:
                errors.append(_("The boot partition must be a primary partition."))

        return errors

class IPSeriesPPC(PPC):
    _minBootPartSize = 4
    _maxBootPartSize = 10

    def bootDevice(self):
        # use booty's PReP-picking algorithm
        return self.anaconda.id.bootloader.pickPReP()

    def bootloaderChoices(self, bl):
        ret = {}

        bootDev = self.bootDevice()
        if not bootDev:
            return ret

        if bootDev.type == "mdarray":
            ret["boot"] = (bootDev.name, N_("RAID Device"))
            ret["mbr"] = (bl.drivelist[0], N_("Master Boot Record (MBR)"))
        else:
            ret["boot"] = (bootDev.name, N_("PPC PReP Boot"))

        return ret

    def checkBootRequest(self, req):
        errors = PPC.checkBootRequest(self, req)

        bootPart = getattr(req, "partedPartition", None)
        if not bootPart:
            return errors

        # All of the above just checks the PPC PReP boot partitions.  We still
        # need to make sure that whatever /boot is on also meets these criteria.
        if req == self.bootDevice():
            # However, this check only applies to prepboot.
            if bootPart.geometry.end * bootPart.geometry.device.sectorSize / (1024.0 * 1024) > 4096:
                errors.append(_("The boot partition must be within the first 4MB of the disk."))

            try:
                req = self.anaconda.id.storage.mountpoints["/boot"]
            except KeyError:
                req = self.anaconda.id.storage.rootDevice

            return errors + self.checkBootRequest(req)
        else:
            return errors

    def setDefaultPartitioning(self):
        ret = PPC.setDefaultPartitioning(self)
        ret.append(PartSpec(fstype="prepboot", size=4,
                            weight=self.weight(fstype="prepboot")))
        return ret

    def weight(self, fstype=None, mountpoint=None):
        if fstype and fstype == "prepboot":
            return 5000
        elif mountpoint and mountpoint == "/boot":
            return 2000
        else:
            return 0

class NewWorldPPC(PPC):
    _disklabel_types = ["mac"]
    _minBootPartSize = (800.00 / 1024.00)
    _maxBootPartSize = 1

    def bootDevice(self):
        bootDev = None

        for part in self.anaconda.id.storage.partitions:
            if part.format.type == "appleboot" and self.validBootPartSize(part.size):
                bootDev = part
                # if we're only picking one, it might as well be the first
                break

        return bootDev

    def bootloaderChoices(self, bl):
        ret = {}

        bootDev = self.bootDevice()
        if not bootDev:
            return ret

        if bootDev.type == "mdarray":
            ret["boot"] = (bootDev.name, N_("RAID Device"))
            ret["mbr"] = (bl.drivelist[0], N_("Master Boot Record (MBR)"))
        else:
            ret["boot"] = (bootDev.name, N_("Apple Bootstrap"))
            for (n, device) in enumerate(self.anaconda.id.storage.partitions):
                if device.format.type == "appleboot" and device.path != bootDev.path:
                    ret["boot%d" % n] = (device.path, N_("Apple Bootstrap"))

        return ret

    def checkBootRequest(self, req):
        errors = PPC.checkBootRequest(self, req)

        if not req or req.type != "partition" or not req.disk:
            return errors

        disk = req.disk.format.partedDisk

        # Check that we're a Mac disk label
        if not disk.type in self.diskLabelTypes:
            errors.append(_("%s must have a mac disk label.") % req.disk.name)

        # All of the above just checks the appleboot partitions.  We still
        # need to make sure that whatever /boot is on also meets these criteria.
        if req == self.bootDevice():
            try:
                req = self.anaconda.id.storage.mountpoints["/boot"]
            except KeyError:
                req = self.anaconda.id.storage.rootDevice

            return errors + self.checkBootRequest(req)
        else:
            return errors

    def setDefaultPartitioning(self):
        ret = Platform.setDefaultPartitioning(self)
        ret.append(PartSpec(fstype="appleboot", size=1, maxSize=1,
                            weight=self.weight(fstype="appleboot")))
        return ret

    def weight(self, fstype=None, mountpoint=None):
        if fstype and fstype == "appleboot":
            return 5000
        elif mountpoint and mountpoint == "/boot":
            return 2000
        else:
            return 0

class PS3(PPC):
    _disklabel_types = ["msdos"]

    def __init__(self, anaconda):
        PPC.__init__(self, anaconda)

class S390(Platform):
    _bootFSTypes = ["ext4", "ext3", "ext2"]
    _packages = ["s390utils"]
    _supportsLvmBoot = True

    def __init__(self, anaconda):
        Platform.__init__(self, anaconda)

    def requiredDiskLabelType(self, device_type):
        """The required disklabel type for the specified device type."""
        if device_type == parted.DEVICE_DASD:
            return "dasd"

        return super(S390, self).requiredDiskLabelType(device_type)

    def setDefaultPartitioning(self):
        """Return the default platform-specific partitioning information."""
        return [PartSpec(mountpoint="/boot", fstype=self.defaultBootFSType, size=500,
                         weight=self.weight(mountpoint="/boot"), asVol=True,
                         singlePV=True)]

    def weight(self, fstype=None, mountpoint=None):
        if mountpoint and mountpoint == "/boot":
            return 5000
        else:
            return 0

class Sparc(Platform):
    _disklabel_types = ["sun"]

    @property
    def minimumSector(self, disk):
        (cylinders, heads, sectors) = disk.device.biosGeometry
        start = long(sectors * heads)
        start /= long(1024 / disk.device.sectorSize)
        return start+1

class X86(EFI):
    _bootFSTypes = ["ext4", "ext3", "ext2"]
    _packages = ["grub"]
    _supportsMdRaidBoot = True

    def __init__(self, anaconda):
        EFI.__init__(self, anaconda)

        if self.isEfi:
            self._disklabel_types = ["gpt"]
        else:
            self._disklabel_types = ["msdos", "gpt"]

    def bootDevice(self):
        if self.isEfi:
            return EFI.bootDevice(self)
        else:
            return Platform.bootDevice(self)

    def bootloaderChoices(self, bl):
        if self.isEfi:
            return EFI.bootloaderChoices(self, bl)

        bootDev = self.bootDevice()
        ret = {}

        if not bootDev:
            return {}

        if bootDev.type == "mdarray":
            ret["boot"] = (bootDev.name, N_("RAID Device"))
            ret["mbr"] = (bl.drivelist[0], N_("Master Boot Record (MBR)"))
        else:
            ret["boot"] = (bootDev.name, N_("First sector of boot partition"))
            ret["mbr"] = (bl.drivelist[0], N_("Master Boot Record (MBR)"))

        return ret

    @property
    def maxBootPartSize(self):
        if self.isEfi:
            return EFI._maxBootPartSize
        else:
            return Platform._maxBootPartSize

    @property
    def minBootPartSize(self):
        if self.isEfi:
            return EFI._minBootPartSize
        else:
            return Platform._minBootPartSize

    def setDefaultPartitioning(self):
        if self.isEfi:
            return EFI.setDefaultPartitioning(self)
        else:
            return Platform.setDefaultPartitioning(self)

def getPlatform(anaconda):
    """Check the architecture of the system and return an instance of a
       Platform subclass to match.  If the architecture could not be determined,
       raise an exception."""
    if iutil.isAlpha():
        return Alpha(anaconda)
    elif iutil.isIA64():
        return IA64(anaconda)
    elif iutil.isPPC():
        ppcMachine = iutil.getPPCMachine()

        if (ppcMachine == "PMac" and iutil.getPPCMacGen() == "NewWorld"):
            return NewWorldPPC(anaconda)
        elif ppcMachine in ["iSeries", "pSeries"]:
            return IPSeriesPPC(anaconda)
        elif ppcMachine == "PS3":
            return PS3(anaconda)
        else:
            raise SystemError, "Unsupported PPC machine type"
    elif iutil.isS390():
        return S390(anaconda)
    elif iutil.isSparc():
        return Sparc(anaconda)
    elif iutil.isX86():
        return X86(anaconda)
    else:
        raise SystemError, "Could not determine system architecture."