#!/usr/bin/env python
#
#  Copyright (C) 2002 Cluster File Systems, Inc.
#   Author: Robert Read <rread@clusterfs.com>

#   This file is part of Lustre, http://www.lustre.org.
#
#   Lustre is free software; you can redistribute it and/or
#   modify it under the terms of version 2 of the GNU General Public
#   License as published by the Free Software Foundation.
#
#   Lustre 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 Lustre; if not, write to the Free Software
#   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#

"""
lmc - lustre configurtion data  manager

 Basic plan for lmc usage:
  lmc --output config.xml --node nodename nid nettype [port=2346]
  lmc --merge config.xml  --lov lovname stripsize stripeoffset
  lmc --merge config.xml  --ost /dev/name nodename lovname [size=9999]
  lmc --merge config.xml  --mtpt /mnt/lustre lovname nodename
"""

import sys, getopt, string
import xml.dom.minidom
from xml.dom.ext import PrettyPrint
from xml.xpath import Evaluate

DEFAULT_PORT = 888 # XXX What is the right default acceptor port to use?

def usage():
    print """usage: lmc [--node --ost | --mtpt | --lov] args
Commands:
--node node_name hostname nettype [port]
   Node_name is used to refer to this node during the configure process.
   Nettype is either tcp, elan, or gm.

--lov lov_name mdc_name stripe_sz stripe_off pattern
   Creates a logical volume 

--mds node_name device [size]

--ost device node_name lov_name [size]
   Creates an OBD/OST/OSC configuration triplet for a new device.
   When used on "host", the device will be initialized and the OST
   will be enabled. On client nodes, the OSC will be avaiable.
   If lov_name is used, this device is added to lov. 

--mtpt node_name mds_name lov_name /mnt/point
   Creates a client mount point.

Options:
--merge="xml file"  Add the new objects to an existing file
--format            Format the partitions if unformated
--reformat          Reformat partitions (this should be an lconf arg,
                    I think)
"""
    sys.exit(1)

def error(*args):
    msg = string.join(map(str,args))
    print msg
    sys.exit(1)
    
#
# manage names and uuids
# need to initialize this by walking tree to ensure
# no duplicate names or uuids are created.
# this are just place holders for now.
# consider changing this to be like OBD-dev-host
def new_name(base):
    ctr = 2
    ret = base
    while names.has_key(ret):
        ret = "%s_%d" % (base, ctr)
        ctr = 1 + ctr
    names[ret] = 1
    return ret

def get_uuid(name):
    return "%s_UUID" % (name)

def new_lustre(dom):
    """Create a new empty lustre document"""
    str = """<lustre> </lustre>"""
    return dom.parseString(str)

names = {}
uuids = {}
def init_names(lustre):
    """initialize auto-name generation tables"""
    global names, uuids
    # get all elements that contain a name attribute
    for n in Evaluate("//@name/..", lustre):
        names[n.getAttribute("name")] = 1
        uuids[n.getAttribute("uuid")] = 1

class GenConfig:
    doc = None
    dom = None
    def __init__(self, doc):
        self.doc = doc

    def ref(self, type, uuid):
        """ generate <[type]_ref uuidref="[uuid]"/> """
        tag = "%s_ref" % (type)
        ref = self.doc.createElement(tag)
        ref.setAttribute("uuidref", uuid)
        return ref
    
    def newService(self, tag, name, uuid):
        """ create a new  service elmement, which requires name and uuid attributes """
        new = self.doc.createElement(tag)
        new.setAttribute("name", name);
        new.setAttribute("uuid", uuid);
        return new
    
    def addText(self, node, str):
        txt = self.doc.createTextNode(str)
        node.appendChild(txt)

    def addElement(self, node, tag, str=None):
        """ create a new element and add it as a child to node. If str is passed,
            a text node is created for the new element"""
        new = self.doc.createElement(tag)
        if str:
            self.addText(new, str)
        node.appendChild(new)
        return new

    def network(self, name, uuid, hostname, net, port=0):
        """create <network> node"""
        network = self.newService("network", name, uuid)
        network.setAttribute("type", net);
        self.addElement(network, "server", hostname)
        if port:
            self.addElement(network, "port", "%d" %(port))
        return network

    def node(self, name, uuid):
        """ create a host """
        node = self.newService("node", name, uuid)
        return node

    def obd(self, name, uuid, fs, devname, format, dev_size=0):
        obd = self.newService("obd", name, uuid)
        obd.setAttribute('type', 'obdfilter')
        self.addElement(obd, "fstype", fs)
        dev = self.addElement(obd, "device", devname)
        if (dev_size):
            dev.setAttribute("size", "%s" % (dev_size))
        self.addElement(obd, "autoformat", format)
        return obd

    def osc(self, name, uuid, obd_uuid, net_uuid):
        osc = self.newService("osc", name, uuid)
        osc.appendChild(self.ref("ost", net_uuid))
        osc.appendChild(self.ref("obd", obd_uuid))
        return osc

    def ost(self, name, uuid, obd_uuid, net_uuid):
        ost = self.newService("ost", name, uuid)
        ost.appendChild(self.ref("network", net_uuid))
        ost.appendChild(self.ref("obd", obd_uuid))
        return ost

    def lov(self, name, uuid, stripe_sz, stripe_off, pattern):
        lov = self.newService("lov", name, uuid)
        devs = self.addElement(lov, "devices" )
        devs.setAttribute("stripesize", stripe_sz)
        devs.setAttribute("stripeoffset", stripe_off)
        devs.setAttribute("pattern", pattern)
        return lov

    def mds(self, name, uuid, fs, devname, format, net_uuid, failover_uuid = "", dev_size=0 ):
        mds = self.newService("mds", name, uuid)
        self.addElement(mds, "fstype", fs)
        dev = self.addElement(mds, "device", devname)
        if dev_size:
            dev.setAttribute("size", "%s" % (dev_size))
        self.addElement(mds, "autoformat", format)
        mds.appendChild(self.ref("network", net_uuid))
        if failover_uuid:
            mds.appendChild(self.ref("failover", failover_uuid))
        return mds

    def mdc(self, name, uuid, mds_uuid):
        mdc = self.newService("mdc", name, uuid)
        mdc.appendChild(self.ref("mds", mds_uuid))
        return mdc

    def mountpoint(self, name, uuid, mdc_uuid, osc_uuid, path):
        mtpt = self.newService("mtpt", name, uuid)
        mtpt.appendChild(self.ref("mdc", mdc_uuid))
        mtpt.appendChild(self.ref("osc", osc_uuid))
        self.addElement(mtpt, "path", path)
        return mtpt

def findByName(lustre, name, tag = "*"):
    path = '//%s[@name="%s"]' % (tag, name)
    ret = Evaluate(path, lustre)
    if ret:
        return ret[0]
    return None
    
# XXX: assumes only one network element per node. will fix this
# as soon as support for routers is added
def get_net_uuid(lustre, node_name):
    """ get a network uuid for a node_name """
    node = findByName(lustre, node_name, "node")
    if not node:
        error ("node not found:", node_name)
    net = Evaluate("./network", node)
    if net:
        return net[0].getAttribute("uuid")
    return None

def lov_add_osc(gen, lov, osc_uuid):
    devs = Evaluate("devices", lov)
    if len(devs) == 1:
        devs[0].appendChild(gen.ref("osc", osc_uuid))
    else:
        error("No devices element found for LOV:", lov)
                            
    
#
# Create a new obd, osc, and ost. Add them to the DOM.
#
def add_ost(gen, lustre, options, args):
    if len(args) < 3:
        usage()

    devname = args[0]
    node_name = args[1]
    lovname = args[2]
    if len(args) > 3:
        size = args[3]
    else:
        size = 0

    obdname = new_name(node_name+"_" + "obd")
    oscname = new_name(node_name+"_"+"osc")
    ostname = new_name(node_name+"_"+"ost")
    obd_uuid = get_uuid(obdname)
    ost_uuid = get_uuid(ostname)
    osc_uuid = get_uuid(oscname)

    net_uuid = get_net_uuid(lustre, node_name)
    if not net_uuid:
        error("NODE: ", node_name, "not found")
    
    lov = findByName(lustre, lovname, "lov")
    if not lov:
        error("LOV:", lovname, "not found.")

    obd = gen.obd(obdname, obd_uuid,  "extN", devname, "no", size)
    ost = gen.ost(ostname, ost_uuid, obd_uuid, net_uuid)
    osc = gen.osc(oscname, osc_uuid, obd_uuid, ost_uuid)
    
    lov_add_osc(gen, lov, osc_uuid)
    lustre.appendChild(obd)
    lustre.appendChild(osc)
    lustre.appendChild(ost)
                   
def add_node(gen, lustre, options, args):
    """ create a node with a network config """
    if len(args) < 3:
        usage()

    name = args[0]
    nid = args[1]
    nettype = args[2]

    if nettype == 'tcp':
        if len(args) > 3:
            port = int(args[3])
        else:
            port = DEFAULT_PORT
        
    elif nettype in ('elan', 'gm'):
        port = 0
    else:
        print "Unknown nettype: ", nettype
        sys.exit(2)

    uuid = get_uuid(name)
    node = gen.node(name, uuid)
    net_name = name+"_net"
    net_uuid = get_uuid(net_name)
    node.appendChild(gen.network(net_name, net_uuid, nid, nettype, port))
    lustre.appendChild(node)


def add_lov(gen, lustre, options, args):
    """ create a lov """
    if len(args) < 4:
        usage()

    name = args[0]
    stripe_sz = args[1]
    stripe_off = args[2]
    pattern = args[3]

    ret = findByName(lustre, name, "lov")
    if ret:
        error("LOV: ", name, " already exists.")

    uuid = get_uuid(name)
    lov = gen.lov(name,uuid,stripe_sz, stripe_off, pattern)
    lustre.appendChild(lov)

def add_mtpt(gen, lustre, options, args):
    """ create mtpt on a node """
    if len(args) < 4:
        usage()

    node_name = args[0]
    mdc_name = args[1]
    lov_name = args[2]
    path = args[3]

    name = new_name(node_name + "_mtpt")

    ret = findByName(lustre, name, "mountpoint")
    if ret:
        error("MOUNTPOINT: ", name, " already exists.")

    ret = findByName(lustre, lov_name, "lov")
    if not ret:
        error("LOV: ", lov_name, " not found.")
    lov_uuid = ret.getAttribute("uuid")

    ret = findByName(lustre, mdc_name, "mdc")
    if not ret:
        error("MDC: ", mdc_name, " not found.")
    mdc_uuid = ret.getAttribute("uuid")

    uuid = get_uuid(name)
    mtpt = gen.mountpoint(name, uuid, mdc_uuid, lov_uuid, path)
    lustre.appendChild(mtpt)


def add_mds(gen, lustre, options, args):
    if len(args) < 3:
        usage()

    node_name = args[0]
    devname = args[1]
    if len(args) > 3:
        size = args[3]
    else:
        size = 0

    ret = findByName(lustre, node_name, "node")

    mds_name = new_name(node_name+"_" + "mds")
    mdc_name = new_name(node_name+"_"+"mdc")
    mds_uuid = get_uuid(mds_name)
    mdc_uuid = get_uuid(mdc_name)

    net_uuid = get_net_uuid(lustre, node_name)
    if not net_uuid:
        error("NODE: ", node_name, "not found")


    mds = gen.mds(mds_name, mds_uuid, "extN", devname, "no", net_uuid)
    mdc = gen.mdc(mdc_name, mdc_uuid, mds_uuid)
    lustre.appendChild(mds)
    lustre.appendChild(mdc)
                   

#
# Command line processing
#

def parse_cmdline(argv):
    short_opts = "ho:i:"
    long_opts = ["ost", "mtpt", "lov", "node", "mds",
                 "merge=", "format", "reformat", "output=",
                 "in=", "help"]
    opts = []
    args = []
    options = {}
    try:
        opts, args = getopt.getopt(argv, short_opts, long_opts)
    except getopt.GetoptError:
        print "invalid opt"
        usage()

    for o, a in opts:
        if o in ("-h", "--help"):
            usage()
        if o in ("-o", "--output"):
            options['output'] = a
        if o == "--ost":
            options['ost'] = 1
        if o == "--mds":
            options['mds'] = 1
        if o == "--node":
            options['node'] = 1
        if o == "--lov":
            options['lov'] = 1
        if o == "--mtpt":
            options['mtpt'] = 1
        if o == "--merge":
            options['merge'] = a
        if o == "--format":
            options['format'] = 1
        if o  == "--reformat":
            options['reformat'] = 1
        if o  in ("--in" , "-i"):
            options['in'] = a
            
    return options, args

def main():
    options, args = parse_cmdline(sys.argv[1:])
    outFile = '-'

    if options.has_key('merge'):
        outFile = options['merge']
        doc = xml.dom.minidom.parse(outFile)
    elif options.has_key('in'):
        doc = xml.dom.minidom.parse(options['in'])
    else:
        doc = new_lustre(xml.dom.minidom)

    if options.has_key('output'):
        outFile = options['output']

    lustre = doc.documentElement
    init_names(lustre)
    lustre = doc.documentElement
    if lustre.tagName != "lustre":
        print "Existing config not valid."
        sys.exit(1)

    gen = GenConfig(doc)
    if options.has_key('ost'):
        add_ost(gen, lustre, options, args)
    elif options.has_key('node'):
        add_node(gen, lustre, options, args)
    elif options.has_key('mtpt'):
        add_mtpt(gen, lustre, options, args)
    elif options.has_key('lov'):
        add_lov(gen, lustre, options, args)
    elif options.has_key('mds'):
        add_mds(gen, lustre, options, args)
    else:
        print "Missing command"
        usage()

    if outFile == '-':
        PrettyPrint(doc)
    else:
        PrettyPrint(doc, open(outFile,"w"))
if __name__ == "__main__":
    main()