# vi: ts=4 expandtab
#
#    Copyright (C) 2011 Canonical Ltd.
#
#    Author: Scott Moser <scott.moser@canonical.com>
#
#    This program is free software: you can redistribute it and/or modify
#    it under the terms of the GNU General Public License version 3, as
#    published by the Free Software Foundation.
#
#    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/>.

import DataSource

from cloudinit import seeddir, log
import cloudinit.util as util
import sys
import os.path
import os
import errno
from xml.dom import minidom
from xml.dom import Node
import base64
import re
import tempfile
import subprocess

class DataSourceOVF(DataSource.DataSource):
    seed = None
    seeddir = seeddir + '/ovf'
    environment = None
    cfg = { }
    userdata_raw = None
    metadata = None
    supported_seed_starts = ( "/" , "file://" )

    def __str__(self):
        mstr="DataSourceOVF"
        mstr = mstr + " [seed=%s]" % self.seed
        return(mstr)

    def get_data(self):
        found = [ ]
        md = { }
        ud = ""

        defaults = { 
            "local-hostname" : "ubuntuhost",
            "instance-id" : "nocloud"
        }

        (seedfile, contents) = get_ovf_env(seeddir)
        if seedfile:
            # found a seed dir
            seed = "%s/%s" % (seeddir,seedfile)
            (md, ud, cfg) = read_ovf_environment(contents)
            self.environment = contents

            found.append(seed)
        else:
            np = { 'iso' : transport_iso9660, 
                   'vmware-guestd' : transport_vmware_guestd, }
            for name, transfunc in np.iteritems():
                (contents, dev, fname) = transfunc()
                if contents: break

            if contents:
                (md, ud, cfg) = read_ovf_environment(contents)
                self.environment = contents
                found.append(name)

        # There was no OVF transports found
        if len(found) == 0:
            return False

        if 'seedfrom' in md and md['seedfrom']:
            seedfrom = md['seedfrom']
            seedfound = False
            for proto in self.supported_seed_starts:
                if seedfrom.startswith(proto):
                    seedfound = proto
                    break
            if not seedfound:
                log.debug("seed from %s not supported by %s" %
                    (seedfrom, self.__class__))
                return False

            (md_seed,ud) = util.read_seeded(seedfrom)
            log.debug("using seeded cache data from %s" % seedfrom)

            md = util.mergedict(md,md_seed)
            found.append(seedfrom)
                    

        md = util.mergedict(md,defaults)
        self.seed = ",".join(found)
        self.metadata = md;
        self.userdata_raw = ud
        self.cfg = cfg
        return True

    def get_public_ssh_keys(self):
        if not 'public-keys' in self.metadata: return([])
        return([self.metadata['public-keys'],])
        
    def get_hostname(self):
        return(self.metadata['local-hostname'])

    # the data sources' config_obj is a cloud-config formated
    # object that came to it from ways other than cloud-config
    # because cloud-config content would be handled elsewhere
    def get_config_obj(self):
        return(self.cfg)

class DataSourceOVFNet(DataSourceOVF):
    seeddir = seeddir + '/ovf-net'
    supported_seed_starts = ( "http://", "https://", "ftp://" )

# this will return a dict with some content
#  meta-data, user-data
def read_ovf_environment(contents):
    props = getProperties(contents)
    md = { }
    cfg = { }
    ud = ""
    cfg_props = [ 'password', ]
    md_props = [ 'seedfrom', 'local-hostname', 'public-keys', 'instance-id' ]
    for prop, val in props.iteritems():
        if prop == 'hostname': prop = "local-hostname"
        if prop in md_props:
            md[prop] = val
        elif prop in cfg_props:
            cfg[prop] = val
        elif prop == "user-data":
            try:
                ud = base64.decodestring(val)
            except:
                ud = val
    return(md, ud, cfg)
        

# returns tuple of filename (in 'dirname', and the contents of the file)
# on "not found", returns 'None' for filename and False for contents
def get_ovf_env(dirname):
    env_names = ("ovf-env.xml", "ovf_env.xml", "OVF_ENV.XML", "OVF-ENV.XML" )
    for fname in env_names:
        if os.path.isfile("%s/%s" % (dirname,fname)):
            fp = open("%s/%s" % (dirname,fname))
            contents = fp.read()
            fp.close()
            return(fname,contents)
    return(None,False)

# transport functions take no input and return
# a 3 tuple of content, path, filename
def transport_iso9660(require_iso=False):

    # default_regex matches values in 
    # /lib/udev/rules.d/60-cdrom_id.rules
    # KERNEL!="sr[0-9]*|hd[a-z]|xvd*", GOTO="cdrom_end"
    envname = "CLOUD_INIT_CDROM_DEV_REGEX"
    default_regex = "^(sr[0-9]+|hd[a-z]|xvd.*)"

    devname_regex = os.environ.get(envname,default_regex)
    cdmatch = re.compile(devname_regex)

    # go through mounts to see if it was already mounted
    fp = open("/proc/mounts")
    mounts = fp.readlines()
    fp.close()

    mounted = { }
    for mpline in mounts:
        (dev,mp,fstype,opts,freq,passno) = mpline.split()
        mounted[dev]=(dev,fstype,mp,False)
        mp = mp.replace("\\040"," ")
        if fstype != "iso9660" and require_iso: continue

        if cdmatch.match(dev[5:]) == None: # take off '/dev/'
            continue
        
        (fname,contents) = get_ovf_env(mp)
        if contents is not False:
            return(contents,dev,fname)

    tmpd = None
    dvnull = None

    devs = os.listdir("/dev/")
    devs.sort()

    for dev in devs:
        fullp = "/dev/%s" % dev

        if fullp in mounted or not cdmatch.match(dev) or os.path.isdir(fullp):
            continue

        fp = None
        try:
            fp = open(fullp, "rb")
            fp.read(512)
            fp.close()
        except:
            if fp: fp.close()
            continue

        if tmpd is None:
            tmpd = tempfile.mkdtemp()
        if dvnull is None:
            try:
                dvnull = open("/dev/null")
            except:
                pass

        cmd = [ "mount", "-o", "ro", fullp, tmpd ]
        if require_iso: cmd.extend(('-t','iso9660'))

        rc = subprocess.call(cmd, stderr=dvnull, stdout=dvnull, stdin=dvnull)
        if rc:
            continue

        (fname,contents) = get_ovf_env(tmpd)

        subprocess.call(["umount", tmpd])

        if contents is not False:
            os.rmdir(tmpd)
            return(contents,fullp,fname)

    if tmpd:
        os.rmdir(tmpd)

    if dvnull:
        dvnull.close()

    return(False, None, None)

def transport_vmware_guestd():
    # http://blogs.vmware.com/vapp/2009/07/selfconfiguration-and-the-ovf-environment.html
    # try:
    #     cmd = ['vmware-guestd', '--cmd', 'info-get guestinfo.ovfEnv']
    #     (out,err) = subp(cmd)
    #     return(out, 'guestinfo.ovfEnv', 'vmware-guestd')
    # except:
    #     # would need to error check here and see why this failed
    #     # to know if log/error should be raised
    #     return(False, None, None)
    return(False, None, None)


def findChild(node,filter_func):
    ret = []
    if not node.hasChildNodes(): return ret
    for child in node.childNodes:
        if filter_func(child): ret.append(child)
    return(ret)

def getProperties(environString):
    dom = minidom.parseString(environString)
    if dom.documentElement.localName != "Environment":
        raise Exception("No Environment Node")

    if not dom.documentElement.hasChildNodes():
        raise Exception("No Child Nodes")

    envNsURI = "http://schemas.dmtf.org/ovf/environment/1"

    # could also check here that elem.namespaceURI == 
    #   "http://schemas.dmtf.org/ovf/environment/1"
    propSections = findChild(dom.documentElement,
        lambda n: n.localName == "PropertySection")

    if len(propSections) == 0:
        raise Exception("No 'PropertySection's")

    props = { }
    propElems = findChild(propSections[0], lambda n: n.localName == "Property")

    for elem in propElems:
        key = elem.attributes.getNamedItemNS(envNsURI,"key").value
        val = elem.attributes.getNamedItemNS(envNsURI,"value").value
        props[key] = val

    return(props)

datasources = (
  ( DataSourceOVF, ( DataSource.DEP_FILESYSTEM, ) ),
  ( DataSourceOVFNet, 
    ( DataSource.DEP_FILESYSTEM, DataSource.DEP_NETWORK ) ),
)

# return a list of data sources that match this set of dependencies
def get_datasource_list(depends):
    return(DataSource.list_from_depends(depends, datasources))

if __name__ == "__main__":
    import sys
    envStr = open(sys.argv[1]).read()
    props = getProperties(envStr)
    import pprint
    pprint.pprint(props)
    
    md, ud, cfg = read_ovf_environment(envStr)
    print "=== md ==="
    pprint.pprint(md)
    print "=== ud ==="
    pprint.pprint(ud)
    print "=== cfg ==="
    pprint.pprint(cfg)