#!/bin/bash

# iff executed under VERBOSE=yes provide more information
verbose() {
  if [[ "$VERBOSE" == "yes" ]] ; then
    echo "$*"
  fi
}

usage() { 
  echo -e "Usage: $0 [OPTION]..." 1>&2
  echo -e "\t-f: Force update, even if running on active node" 1>&2
}

FORCE_ACTIVE_NODE=false

while getopts "fh" opt; do
    case "${opt}" in
        f)
            FORCE_ACTIVE_NODE=true
            ;;
        h)
            usage; exit 0;
            ;;
        *)
            usage; exit 1;
            ;;
    esac
done
shift $((OPTIND-1))

nodename=$(/usr/sbin/ngcp-nodename 2>/dev/null || echo "unknown")
if [ "${nodename}" = "unknown" ] ; then
  echo "Error: nodename could not be identified." >&2
  exit 1
fi

/etc/init.d/mysql start || true
. /etc/mysql/sipwise.cnf

if [ -z "${SIPWISE_DB_PASSWORD}" ] ; then
  echo 'Error: SIPWISE_DB_PASSWORD is unset (using /etc/mysql/sipwise.cnf).' >&2
  exit 1
fi

# check connection with sipwise user
if ! mysql -usipwise -p${SIPWISE_DB_PASSWORD} -e 'SELECT 1;' 1>/dev/null 2>/dev/null ; then
  echo 'Error: cant connect to local MySQL with sipwise user' >&2
  exit 1
fi

# support automated installation
if [ -n "$AUTOMATED_INSTALL_MODE" ] ; then
  echo "Running in automated installation mode, ignoring check for empty db_schema."
else
  if [ "$(mysql -usipwise -p${SIPWISE_DB_PASSWORD} -e 'use ngcp; select * from db_schema;' 2>/dev/null)" = "" ] ; then
    echo "================================================================="
    echo "Warning: the db_schema table of the ngcp database is empty."
    echo "Are you sure you want to proceed with applying db-schema changes?"
    echo "This will DROP and then re-initialize your existing database."
    printf "Please type 'agree' to really continue: "

    unset AGREE
    read AGREE
    if [ "$AGREE" != "agree" ]; then
      echo "Exiting as requested." >&2
      exit 1
    fi
  fi
fi

if ! mysql -usipwise -p${SIPWISE_DB_PASSWORD} -e 'use ngcp;' 2>/dev/null ; then
  mysql -usipwise -p${SIPWISE_DB_PASSWORD} < /usr/share/ngcp-db-schema/db_scripts/init/0005_create_ngcp.up
fi

if ! mysql -usipwise -p${SIPWISE_DB_PASSWORD} -e 'use ngcp;' 2>/dev/null ; then
  echo 'Error: ngcp database does not exist.' >&2
  exit 1
fi

if ! mysql -usipwise -p${SIPWISE_DB_PASSWORD} ngcp -e 'describe db_schema'  >/dev/null; then
  echo 'Error: db_schema table does not exit.' >&2
  exit 1
fi

running_on_active_node() {
  if [ "$nodename" = "spce" ] ; then
    return 1
  else
    if /usr/sbin/ngcp-check_active -q ; then
      if $FORCE_ACTIVE_NODE; then
        verbose "Force update on active node as requested."
      else
        verbose "This seems to be the active node, nothing to do."
      fi
      return 0
    else
      verbose "This seems to be the inactive node, applying revisions."
      return 1
    fi
  fi
}

if running_on_active_node ; then
  ACTIVE_NODE=true
else
  ACTIVE_NODE=false
fi

apply_revision() {
  [ -n "$1" ] || return 1

  rev="$1"
  revname="$(basename $rev)"

  printf "Applying revision script %s: " "$rev"
  if mysql -usipwise -p${SIPWISE_DB_PASSWORD} < "$rev" ; then
    echo done
  else
    echo "failed. :(" >&2
    echo "Please resolve the problem and run ngcp-update-db-schema again." >&2
    exit 1
  fi

  if mysql -usipwise -p${SIPWISE_DB_PASSWORD} ngcp -e "insert into db_schema values (0, '${revname}', \""${nodename}"\", CURRENT_TIMESTAMP);" ; then
    verbose "Marked revision $rev as applied."
  else
    echo "Error while executing DB commands using revision $rev for node $nodename" >&2
    exit 1
  fi
}

# execute the rev script iff there's no entry for *any* host yet
apply_revs() {
  [ -n "$1" ] || return 1

  revs="$1"

  # generate list of rev scripts that are node specific, used inside
  # missing_revision's ngcp-check-rev-applied ... --node $nodename
  for rev in $revs ; do
    revision_file="$(find /usr/share/ngcp-db-schema/ -name "$rev")"

    case "$revision_file" in
      *_not_replicated.up)
        node_revs="$node_revs $rev"
        ;;
    esac
  done

  for missing_revision in \
    $( {
        ngcp-check-rev-applied --schema db_schema --revision $revs                         | awk '/^No match for revision/ {print $5}' ;
        ngcp-check-rev-applied --schema db_schema --revision $node_revs --node "$nodename" | awk '/^No match for revision/ {print $5}' ;
       } | sort -z -n -u ) ; do
    revision_file="$(find /usr/share/ngcp-db-schema/ -name "$missing_revision")"

    # execute the rev script iff there's no entry for the *current* host yet
    case "$revision_file" in
      *_not_replicated.up)
        if ngcp-check-rev-applied --schema db_schema --revision $missing_revision --node "$nodename" | grep -q 'already executed' ; then
          continue
        fi
        ;;
    esac

    if [ -r "$revision_file" ] ; then
      apply_revision "$revision_file"
    else
      echo "Warning: missing revision $missing_revision identified but could not find according db-schema file."
    fi
  done
}


revision_wrapper() {
  [ -n "$1" ] || return 1

  local revlist

  for rev in $* ; do

    if ! [ -r "$rev" ] ; then
      echo "Error: $rev can not be read." >&2
      exit 1
    fi

    cd $(dirname $rev) || exit 1 # would fail if a script references a file (like language_strings.txt) in its CWD

    revname="$(basename $rev)"

    case "$revname" in
      # the scripts that should be executed on *all* hosts, no matter whether
      # they are active or inactive, since the script's content doesn't get replicated
      # NOTE: the actual logic is inside the apply_revs to avoid *_not_replicated.up
      # scripts being executed independent from the other ones
      *_not_replicated.up)
        revlist="$revlist $(basename $rev)"
        ;;
      *)
        if $ACTIVE_NODE ; then
	  if $FORCE_ACTIVE_NODE; then
            revlist="$revlist $(basename $rev)"
	  else
            verbose "Replication script ${revname} noted, nothing to do on active node"
	  fi
        else
          revlist="$revlist $(basename $rev)"
        fi
        ;;
    esac

  done

  apply_revs "$revlist"
}

# make sure we get sorted 10XXX after 9XXX
cd /usr/share/ngcp-db-schema/db_scripts/base/
revision_wrapper $(printf '%s\0' *.up | sort -z -n | while IFS= read -r -d "" file; do \
                   echo /usr/share/ngcp-db-schema/db_scripts/base/$file; done)

cd /usr/share/ngcp-db-schema/db_scripts/diff/
revision_wrapper $(printf '%s\0' *.up | sort -z -n | while IFS= read -r -d "" file; do \
                   echo /usr/share/ngcp-db-schema/db_scripts/diff/$file; done)

echo "Synchronizing passwords with MySQL"
ngcp-sync-constants >/dev/null

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