"""
Builds out filesystem trees/data based on the object tree.
This is the code behind 'cobbler sync'.

Copyright 2006-2008, Red Hat, Inc
Michael DeHaan <mdehaan@redhat.com>

This software may be freely redistributed under the terms of the GNU
general public license.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
"""

import os
import os.path
import shutil
import time
import sub_process
import sys
import glob
import traceback
import errno

import utils
from cexceptions import *
import templar 

import item_distro
import item_profile
import item_repo
import item_system

from utils import _


class PXEGen:
    """
    Handles building out PXE stuff
    """

    def __init__(self,config):
        """
        Constructor
        """
        self.config      = config
        self.api         = config.api
        self.distros     = config.distros()
        self.profiles    = config.profiles()
        self.systems     = config.systems()
        self.settings    = config.settings()
        self.repos       = config.repos()
        self.templar     = templar.Templar(config)
        self.bootloc     = utils.tftpboot_location()

    def copy_bootloaders(self):
        """
        Copy bootloaders to the configured tftpboot directory
        NOTE: we support different arch's if defined in
        /var/lib/cobbler/settings.
        """
        for loader in self.settings.bootloaders.keys():
            path = self.settings.bootloaders[loader]
            newname = os.path.basename(path)
            destpath = os.path.join(self.bootloc, newname)
            utils.copyfile(path, destpath)
        utils.copyfile("/var/lib/cobbler/menu.c32", os.path.join(self.bootloc, "menu.c32"))

        # Copy memtest to tftpboot if package is installed on system          
        for memtest in glob.glob('/boot/memtest*'):
            base = os.path.basename(memtest)
            utils.copyfile(memtest,os.path.join(self.bootloc,"images",base))

    def copy_distros(self):
        """
        A distro is a kernel and an initrd.  Copy all of them and error
        out if any files are missing.  The conf file was correct if built
        via the CLI or API, though it's possible files have been moved
        since or perhaps they reference NFS directories that are no longer
        mounted.

        NOTE:  this has to be done for both tftp and http methods
        """
        # copy is a 4-letter word but tftpboot runs chroot, thus it's required.
        for d in self.distros:
            print _("sync distro: %s") % d.name
            self.copy_single_distro_files(d)

    def copy_single_distro_files(self, d):
        for dirtree in [self.bootloc, self.settings.webdir]: 
            distros = os.path.join(dirtree, "images")
            distro_dir = os.path.join(distros,d.name)
            utils.mkdir(distro_dir)
            kernel = utils.find_kernel(d.kernel) # full path
            initrd = utils.find_initrd(d.initrd) # full path
            if kernel is None or not os.path.isfile(kernel):
                raise CX(_("kernel not found: %(file)s, distro: %(distro)s") % { "file" : d.kernel, "distro" : d.name })
            if initrd is None or not os.path.isfile(initrd):
                raise CX(_("initrd not found: %(file)s, distro: %(distro)s") % { "file" : d.initrd, "distro" : d.name })
            b_kernel = os.path.basename(kernel)
            b_initrd = os.path.basename(initrd)
            if kernel.startswith(dirtree):
                utils.linkfile(kernel, os.path.join(distro_dir, b_kernel))
            else:
                utils.copyfile(kernel, os.path.join(distro_dir, b_kernel))
            if initrd.startswith(dirtree):
                utils.linkfile(initrd, os.path.join(distro_dir, b_initrd))
            else:
                utils.copyfile(initrd, os.path.join(distro_dir, b_initrd))

    def write_all_system_files(self,system):

        profile = system.get_conceptual_parent()
        if profile is None:
            raise CX(_("system %(system)s references a missing profile %(profile)s") % { "system" : system.name, "profile" : system.profile})
        distro = profile.get_conceptual_parent()
        if distro is None:
            raise CX(_("profile %(profile)s references a missing distro %(distro)s") % { "profile" : system.profile, "distro" : profile.distro})

        # this used to just generate a single PXE config file, but now must
        # generate one record for each described NIC ...
 
        counter = 0
        for (name,interface) in system.interfaces.iteritems():

            ip = interface["ip_address"]

            f1 = utils.get_config_filename(system,interface=name)

            # for tftp only ...
            if distro.arch in [ "x86", "x86_64", "standard"]:
                # pxelinux wants a file named $name under pxelinux.cfg
                f2 = os.path.join(self.bootloc, "pxelinux.cfg", f1)
            if distro.arch == "ia64":
                # elilo expects files to be named "$name.conf" in the root
                # and can not do files based on the MAC address
                if ip is not None and ip != "":
                    print _("Warning: Itanium system object (%s) needs an IP address to PXE") % system.name

                filename = "%s.conf" % utils.get_config_filename(system,interface=name)
                f2 = os.path.join(self.bootloc, filename)

            f3 = os.path.join(self.settings.webdir, "systems", f1)

            if system.netboot_enabled and system.is_pxe_supported():
                if distro.arch in [ "x86", "x86_64", "standard"]:
                    self.write_pxe_file(f2,system,profile,distro,False)
                if distro.arch == "ia64":
                    self.write_pxe_file(f2,system,profile,distro,True)
            else:
                # ensure the file doesn't exist
                utils.rmfile(f2)

        counter = counter + 1
        

    def make_pxe_menu(self):
        # only do this if there is NOT a system named default.
        default = self.systems.find(name="default")
        if default is not None:
            return
        
        fname = os.path.join(self.bootloc, "pxelinux.cfg", "default")

        # read the default template file
        template_src = open("/etc/cobbler/pxedefault.template")
        template_data = template_src.read()

        # sort the profiles
        profile_list = [profile for profile in self.profiles]
        def sort_name(a,b):
           return cmp(a.name,b.name)
        profile_list.sort(sort_name)

        # build out the menu entries
        pxe_menu_items = ""
        for profile in profile_list:
            distro = profile.get_conceptual_parent()
            # xen distros can be ruled out as they won't boot
            if distro.name.find("-xen") != -1:
                continue
            contents = self.write_pxe_file(None,None,profile,distro,False,include_header=False)
            if contents is not None:
                pxe_menu_items = pxe_menu_items + contents + "\n"

        # if we have any memtest files in images, make entries for them
        # after we list the profiles
        memtests = glob.glob(self.bootloc + "/images/memtest*")
        if len(memtests) > 0:
            pxe_menu_items = pxe_menu_items + "\n\n"
            for memtest in glob.glob(self.bootloc + '/images/memtest*'):
                base = os.path.basename(memtest)
                contents = self.write_memtest_pxe("/images/%s" % base)
                pxe_menu_items = pxe_menu_items + contents + "\n"
              
        # save the template.
        metadata = { "pxe_menu_items" : pxe_menu_items }
        outfile = os.path.join(self.bootloc, "pxelinux.cfg", "default")
        self.templar.render(template_data, metadata, outfile, None)
        template_src.close()

    def write_memtest_pxe(self,filename):
        """
        Write a configuration file for memtest
        """

        # just some random variables
        template = None
        metadata = {}
        buffer = ""

        template = "/etc/cobbler/pxeprofile.template"

        # store variables for templating
        metadata["menu_label"] = "MENU LABEL %s" % os.path.basename(filename)
        metadata["profile_name"] = os.path.basename(filename)
        metadata["kernel_path"] = "/images/%s" % os.path.basename(filename)
        metadata["initrd_path"] = ""
        metadata["append_line"] = ""

        # get the template
        template_fh = open(template)
        template_data = template_fh.read()
        template_fh.close()

        # return results
        buffer = self.templar.render(template_data, metadata, None)
        return buffer



    def write_pxe_file(self,filename,system,profile,distro,is_ia64, include_header=True):
        """
        Write a configuration file for the boot loader(s).
        More system-specific configuration may come in later, if so
        that would appear inside the system object in api.py

        NOTE: relevant to tftp only
        """

        # ---
        # system might have netboot_enabled set to False (see item_system.py), if so, 
        # don't do anything else and flag the error condition.
        if system is not None and not system.netboot_enabled:
            return None

        # ---
        # just some random variables
        template = None
        metadata = {}
        buffer = ""

        # ---
        # find kernel and initrd
        kernel_path = os.path.join("/images",distro.name,os.path.basename(distro.kernel))
        initrd_path = os.path.join("/images",distro.name,os.path.basename(distro.initrd))
        
        # Find the kickstart if we inherit from another profile
        kickstart_path = utils.blender(self.api, True, profile)["kickstart"]

        # ---
        # choose a template
        if system is None:
            template = "/etc/cobbler/pxeprofile.template"
        elif not is_ia64:
            template = "/etc/cobbler/pxesystem.template"
        else:
            template = "/etc/cobbler/pxesystem_ia64.template"

        # now build the kernel command line
        if system is not None:
            blended = utils.blender(self.api, True, system)
        else:
            blended = utils.blender(self.api, True,profile)
        kopts = blended["kernel_options"]

        # generate the append line
        append_line = "append %s" % utils.hash_to_string(kopts)
        if not is_ia64:
            append_line = "%s initrd=%s" % (append_line, initrd_path)
        if len(append_line) >= 255 + len("append "):
            print _("warning: kernel option length exceeds 255")

        # kickstart path rewriting (get URLs for local files)
        if kickstart_path is not None and kickstart_path != "":

            if system is not None and kickstart_path.startswith("/"):
                kickstart_path = "http://%s/cblr/svc/op/ks/system/%s" % (blended["http_server"], system.name)
            elif kickstart_path.startswith("/") or kickstart_path.find("/cobbler/kickstarts/") != -1:
                kickstart_path = "http://%s/cblr/svc/op/ks/profile/%s" % (blended["http_server"], profile.name)

            if distro.breed is None or distro.breed == "redhat":
                append_line = "%s ks=%s" % (append_line, kickstart_path)
            elif distro.breed == "suse":
                append_line = "%s autoyast=%s" % (append_line, kickstart_path)
            elif distro.breed == "debian":
                append_line = "%s auto=true url=%s" % (append_line, kickstart_path)
                append_line = append_line.replace("ksdevice","interface")

        # store variables for templating
        metadata["menu_label"] = ""
        if not is_ia64 and system is None:
            metadata["menu_label"] = "MENU LABEL %s" % profile.name
        metadata["profile_name"] = profile.name
        metadata["kernel_path"] = kernel_path
        metadata["initrd_path"] = initrd_path
        metadata["append_line"] = append_line

        # get the template
        template_fh = open(template)
        template_data = template_fh.read()
        template_fh.close()

        # save file and/or return results, depending on how called.
        buffer = self.templar.render(template_data, metadata, None)
        if filename is not None:
            fd = open(filename, "w")
            fd.write(buffer)
            fd.close()
        return buffer