#!/bin/bash
#  $HeadURL$ $LastChangedRevision$

#  Properties
MY_ID=system
PARENT_ID=
MY_PRIVATE_ATTRIBUTES="uname status debian_url"
MY_PUBLIC_ATTRIBUTES="arch release kernel_commandline vm_flag hvm_flag bootmedia engine virttool macaddr pdi dnsclient_flag dnsclient_domain dnsclient_servers serial_console_flag"
MY_ATTRIBUTES="$MY_PRIVATE_ATTRIBUTES $MY_PUBLIC_ATTRIBUTES"
#  Helpers are set explicitly, because order is important.
MY_HELPER_IDS="dns repo boot preseed pdi hardware"

#  My attributes
for MY_ATTRIBUTE in ${MY_ATTRIBUTES^^}; do eval "$MY_ATTRIBUTE="; done

#  Defaults for the questions we ask (should only used here)
DFLT_RELEASE=wheezy
DFLT_ARCH=amd64
DFLT_VM_FLAG=y
DFLT_HVM_FLAG=n
DFLT_BOOTMEDIA=net
DFLT_ENGINE=kvm
DFLT_VIRTTOOL=virt-manager
DFLT_PDI=true
DFLT_MACADDR=
DFLT_DNSCLIENT_FLAG=true
DFLT_DNSCLIENT_DOMAIN=$(dnsdomainname)
DFLT_DNSCLIENT_SERVERS="192.168.1.2"
DFLT_SERIAL_CONSOLE_FLAG=false

#  Other globals 
PRESEEDSERVER_IPADDR=$(host $(uname -n) 2> /dev/null | sed 's/.*has address //')

#  Hooks
init_prologue()
{
    inherit SQLITE_CMD DB_FILE

    #  Create extra tables
    debug 10 "init_prologue: creating extra tables ..."

    #  Why does this table have an allergy to the helper column being called 'helper'? Instead,
    $SQLITE_CMD $DB_FILE "drop table if exists helpers;"
    $SQLITE_CMD $DB_FILE "create table helpers (
                              helper text not null,
                              parent_helper text not null,
                              primary key (helper)
                          );"
    $SQLITE_CMD $DB_FILE "drop table if exists attributes;"
    $SQLITE_CMD $DB_FILE "create table attributes (
                              helper text not null,
                              attribute text not null,
			      public integer check (public == 0 or public == 1),
                              primary key (helper, attribute)
                          );"
    $SQLITE_CMD $DB_FILE "drop table if exists attribute_values;"
    $SQLITE_CMD $DB_FILE "create table attribute_values (
                              helper text not null,
                              attribute text not null,
                              uname text not null,
                              value text not null,
                              primary key (helper, attribute, uname)
                          );"
   
    return 0
}

init_epilogue()
{
    #  This view will help load_local_attributes() and load_inherited_attributes().
    #  It consists of a deeper and deeper recursion (via helpers) to determine
    #  the attributes that an ancestor table makes public. And then tagged on the
    #  beginning is a rather contorted view of the attributes table to fit into
    #  the same form as the others (which just says that an owner has permission to
    #  view its own attributes (but which helps to provide a *single* interface
    #  for looking this stuff up in).
    $SQLITE_CMD $DB_FILE "drop view if exists attribute_viewing_permissions;"
    $SQLITE_CMD $DB_FILE "create view attribute_viewing_permissions as
                              select helper as viewing_helper,helper as owning_helper,attribute from attributes 
                          union
                              select h1.helper,attributes.helper,attributes.attribute from helpers as h1,attributes where h1.parent_helper == attributes.helper and attributes.public == 1 
                          union
                              select h1.helper,attributes.helper,attributes.attribute from helpers as h1,helpers as h2,attributes where h1.parent_helper == h2.helper and h2.parent_helper == attributes.helper and attributes.public == 1 
                          union
                              select h1.helper,attributes.helper,attributes.attribute from helpers as h1,helpers as h2,helpers as h3,attributes where h1.parent_helper == h2.helper and h2.parent_helper == h3.helper and h3.parent_helper == attributes.helper and attributes.public == 1 
                          union
                              select h1.helper,attributes.helper,attributes.attribute from helpers as h1,helpers as h2,helpers as h3,helpers as h4,attributes where h1.parent_helper == h2.helper and h2.parent_helper == h3.helper and h3.parent_helper == h4.helper and h4.parent_helper == attributes.helper and attributes.public == 1 
                          union
                              select h1.helper,attributes.helper,attributes.attribute from helpers as h1,helpers as h2,helpers as h3,helpers as h4,helpers as h5,attributes where h1.parent_helper == h2.helper and h2.parent_helper == h3.helper and h3.parent_helper == h4.helper and h4.parent_helper == h5.helper and h5.parent_helper == attributes.helper and attributes.public == 1 
                          union
                              select h1.helper,attributes.helper,attributes.attribute from helpers as h1,helpers as h2,helpers as h3,helpers as h4,helpers as h5,helpers as h6,attributes where h1.parent_helper == h2.helper and h2.parent_helper == h3.helper and h3.parent_helper == h4.helper and h4.parent_helper == h5.helper and h5.parent_helper == h6.helper and h6.parent_helper == attributes.helper and attributes.public == 1 
                          order by viewing_helper,owning_helper,attribute;"
   return 0
}

edit_prologue()
{
    inherit MY_HELPER_IDS DISPLAY_PROGNAME
    inherit ${MY_ATTRIBUTES^^}
    
    debug 10 "edit_prologue: prompting for changes ..."

    #  VM?
    question --force-ask=true VM_FLAG "VM" "$DFLT_VM_FLAG" "echo \"y or n\"" validate_logical rationalise_logical
    if $VM_FLAG; then
        question --force-ask=true VIRTTOOL "virtualisation tool" "$DFLT_VIRTTOOL" "echo \"virsh or virt-manager\"" "validate_string \"^(virsh|virt-manager)\\\$\"" echo
        question --force-ask=true ENGINE "engine" "$DFLT_ENGINE" "echo \"xen or kvm\"" "validate_string \"^(xen|kvm)\\\$\"" echo
    else
        VIRTTOOL=not-used
        ENGINE=not-used
    fi
    if $VM_FLAG; then
        question --force-ask=true HVM_FLAG "HVM" "$DFLT_HVM_FLAG" "echo \"y or n\"" validate_logical rationalise_logical
    else
        HVM_FLAG=not-used
    fi

    #  Serial console?
    if $VM_FLAG && ! $HVM_FLAG; then
        SERIAL_CONSOLE_FLAG=true
    else
        question --force-ask=true SERIAL_CONSOLE_FLAG "serial console" "$DFLT_SERIAL_CONSOLE_FLAG" "echo \"y or n\"" validate_logical rationalise_logical
    fi

    #  Boot media
    question --force-ask=true BOOTMEDIA "boot media" "$DFLT_BOOTMEDIA" "echo \"net or cd\"" "validate_string \"^(net|cd)\\\$\"" echo

    #  Kernel commandline
    if [ $BOOTMEDIA = net ]; then
        debug 10 "edit_prologue: VM_FLAG=$VM_FLAG, HVM_FLAG=$HVM_FLAG, RELEASE=$RELEASE, UNAME=$UNAME, SERIAL_CONSOLE_FLAG=$SERIAL_CONSOLE_FLAG"
        get_kernel_commandline_net $VM_FLAG $HVM_FLAG $RELEASE $UNAME $SERIAL_CONSOLE_FLAG KERNEL_COMMANDLINE || return $?
    else
        get_kernel_commandline_cd $UNAME KERNEL_COMMANDLINE || return $?
    fi

    #  Arch
    question --force-ask=true ARCH "arch" "$DFLT_ARCH" "echo \"i386 or amd64\"" "validate_string \"^(i386|amd64)\\\$\"" rationalise_arch

    #  Release
    question --force-ask=true RELEASE "release" "$DFLT_RELEASE" "echo \"lenny, squeeze or wheezy\"" "validate_string \"^(lenny|squeeze|wheezy)\\\$\"" rationalise_release

    #  MAC address
    if [ $BOOTMEDIA != net ] && [ "X$MACADDR" = X ]; then
        MACADDR=not-used
    elif [ $BOOTMEDIA != net ]; then
        #  Preserve MAC address for next time
        :
    elif $VM_FLAG && [ "X$MACADDR" = X ]; then
        info "inventing a MAC address ..."
        if [ $ENGINE = xen ]; then
            printf -v MACADDR "00:16:3e:%02x:%02x:%02x" $((RANDOM%256)) $((RANDOM%256)) $((RANDOM%256))
        else
            printf -v MACADDR "52:54:00:%02x:%02x:%02x" $((RANDOM%256)) $((RANDOM%256)) $((RANDOM%256))
        fi
    elif $VM_FLAG; then
        #  Preserve MAC address for next time
        :
    else
        question --force-ask=true MACADDR "MAC address" "$DFLT_MACADDR" "enter MAC address in format xx:xx:xx:xx:xx:xx" validate_macaddr rationalise_macaddr
    fi

    #  Install PDI?
    question --force-ask=true PDI  "install pdi" "$DFLT_PDI"  "echo \"no help available\"" validate_logical rationalise_logical

    #  DNS
    question --force-ask=true DNSCLIENT_FLAG  "DNS client" "$DFLT_DNSCLIENT_FLAG"  help_nohelpavailable validate_logical rationalise_logical
    if $DNSCLIENT_FLAG; then
        question --force-ask=true DNSCLIENT_DOMAIN "DNS domain" "$DFLT_DNSCLIENT_DOMAIN" help_nohelpavailable validate_dnsdomain echo
        question --force-ask=true DNSCLIENT_SERVERS "space-separated IP address(es) of DNS server(s)" "$DFLT_DNSCLIENT_MODE" help_nohelpavailable "validate_list validate_ipaddr" echo
    else
        DNSCLIENT_DOMAIN=not-used
        DNSCLIENT_SERVERS=not-used
    fi

    return 0
}

list_prologue()
{
    :
}

#  Support functions
get_kernel_commandline_net()
{
    #  local for arguments
    local VM_FLAG HVM_FLAG RELEASE UNAME SERIAL_CONSOLE_FLAG KERNEL_COMMANDLINE_REF 
    #  globals
    inherit DNSCLIENT_DOMAIN PRESEEDSERVER_IPADDR PRESEEDSERVER_DIR PRESEEDSERVER_DOCROOT
    #  real local 
    local KERNEL_COMMANDLINE_LOCAL

    [ $# = 6 ] || internal "get_kernel_commandline_net: $#: bad argument count"
    VM_FLAG=$1
    HVM_FLAG=$2
    RELEASE=$3
    UNAME=$4
    SERIAL_CONSOLE_FLAG=$5
    KERNEL_COMMANDLINE_REF=$6

    #  Console
    if $SERIAL_CONSOLE_FLAG; then
        KERNEL_COMMANDLINE_LOCAL+="console=ttyS0,115200 "
    fi

    #  Language
    KERNEL_COMMANDLINE_LOCAL+="debian-installer/language=en "
    #  Country
    KERNEL_COMMANDLINE_LOCAL+="debian-installer/country=US "
    #  Locale
    KERNEL_COMMANDLINE_LOCAL+="debian-installer/locale=en_US.UTF-8 "
    #  Keyboard
    KERNEL_COMMANDLINE_LOCAL+="keyboard-configuration/xkb-keymap=us "
    #  macaroni has multiple NICS
    KERNEL_COMMANDLINE_LOCAL+="netcfg/choose_interface=auto "

    #  Host name and domain
    KERNEL_COMMANDLINE_LOCAL+="netcfg/get_hostname=debian "
    KERNEL_COMMANDLINE_LOCAL+="netcfg/get_domain=$DNSCLIENT_DOMAIN "
    #  IP configuration
    #  PVs boot quicker and therefore make DHCP requests earlier which causes
    #  STP problems on the bridge.
    ! $VM_FLAG || $HVM_FLAG || KERNEL_COMMANDLINE_LOCAL+="netcfg/dhcp_timeout=60 "

    #  On wheezy, the installer is the graphical one. Disable that.
    KERNEL_COMMANDLINE_LOCAL+="DEBIAN_FRONTEND=newt "

    #  The rest
    KERNEL_COMMANDLINE_LOCAL+="preseed/url=http://$PRESEEDSERVER_IPADDR${PRESEEDSERVER_DIR#$PRESEEDSERVER_DOCROOT}/$UNAME.cfg "

    eval "$KERNEL_COMMANDLINE_REF=\"$KERNEL_COMMANDLINE_LOCAL\""

    return 0
}

get_kernel_commandline_cd()
{
    #  local for arguments
    local UNAME KERNEL_COMMANDLINE_REF
    #  globals
    inherit PRESEEDSERVER_IPADDR PRESEEDSERVER_DIR PRESEEDSERVER_DOCROOT
    #  real local 
    local KERNEL_COMMANDLINE_LOCAL

    [ $# = 2 ] || internal "get_kernel_commandline_cd: $#: bad argument count"
    UNAME=$1
    KERNEL_COMMANDLINE_REF=$2

    #  Console
    if $VM_FLAG and ! $HVM_FLAG; then
        KERNEL_COMMANDLINE_LOCAL+="console=ttyS0,115200 "
    fi

    #  The rest
    KERNEL_COMMANDLINE_LOCAL+="preseed/url=http://$PRESEEDSERVER_IPADDR${PRESEEDSERVER_DIR#$PRESEEDSERVER_DOCROOT}/$UNAME.cfg "

    eval "$KERNEL_COMMANDLINE_REF=\"$KERNEL_COMMANDLINE_LOCAL\""

    return 0
}