#!/bin/bash

# Copyright (C) 2008-2021 Rod Roark <rod@sunsetsystems.com>
#
# This program is free software; you can redistribute it and/or
# modify it under the terms of the GNU General Public License
# as published by the Free Software Foundation; either version 2
# of the License, or (at your option) any later version.
#
# This is for restoring a backup created by the "Backup" option
# in OpenEMR's administration menu, which invokes
# interface/main/backup.php.
#
# Xdialog is supported if available... dialog support is also in
# here but is disabled, as it was found to be ugly and clumsy.

DLGCMD=""
NOBUTTONS=""
DEFAULTNO=""
LEFT=""
if [ ! -z "$DISPLAY" -a ! -z "`which Xdialog`" ]; then
  DLGCMD="Xdialog"
  NOBUTTONS="--no-buttons"
  DEFAULTNO="--default-no"
  LEFT="--left"
fi

dlg_msg() {
  if [ ! -z "$DLGCMD" ]; then
    local MSG="$1"
    shift
    while [ ! -z "$1" ]; do
      MSG="$MSG\n$1"
      shift
    done
    $DLGCMD --title 'OpenEMR Restore' $LEFT --msgbox "$MSG" 0 0
    return 0
  fi
  while [ ! -z "$1" ]; do
    echo "$1"
    shift
  done
}

dlg_info() {
  if [ ! -z "$DLGCMD" ]; then
    if [ "$DLGCMD" = "Xdialog" ]; then
      echo "$1"
    fi
    $DLGCMD --title 'OpenEMR Restore' $LEFT --infobox "$1" 0 0
    return 0
  fi
  echo "$1"
}

dlg_fselect() {
  if [ ! -z "$DLGCMD" ]; then
    exec 3>&1
    RESULT=`$DLGCMD --title 'OpenEMR Restore' --backtitle "$1" $NOBUTTONS --fselect $HOME/ 0 70 2>&1 1>&3`
    CODE=$?
    exec 3>&-
    if [ $CODE -eq 0 ]; then
      return 0
    fi
    echo $RESULT
    exit 1
  fi
  echo " "
  read -e -p "$1: " RESULT
}

dlg_yesno() {
  if [ ! -z "$DLGCMD" ]; then
    local MSG="$1"
    shift
    while [ ! -z "$1" ]; do
      MSG="$MSG\n$1"
      shift
    done
    $DLGCMD --title 'OpenEMR Restore' $DEFAULTNO $LEFT --yesno "$MSG" 0 0
    CODE=$?
    exec 3>&-
    if [ $CODE -eq 0 ]; then
      RESULT="1"
    elif [ $CODE -eq 1 ]; then
      RESULT="0"
    else
      exit 1
    fi
    return 0
  fi
  echo " "
  while [ ! -z "$2" ]; do
    echo "$1"
    shift
  done
  read -e -p "$1 [N/y] " RESULT
  RESULT=`expr "$RESULT" : "[yY]"`
  return 0
}

dlg_input() {
  if [ ! -z "$DLGCMD" ]; then
    exec 3>&1
    RESULT=`$DLGCMD --title 'OpenEMR Restore' $LEFT --inputbox "$1" 0 0 2>&1 1>&3`
    CODE=$?
    exec 3>&-
    if [ $CODE -eq 0 ]; then
      return 0
    fi
    echo $RESULT
    exit 1
  fi
  echo " "
  read -e -p "$1 " RESULT
}

dlg_blank_line() {
  if [ -z "$DLGCMD" ]; then
    echo " "
  fi
}

dlg_msg "WARNING: This script is experimental." "It may have serious bugs or omissions." "Use it at your own risk!"

BAKDIR=/tmp/emr_backup

if [ $UID -ne 0 ]; then
  dlg_msg "Error: This script must be executed with root privileges."
  exit 1
fi

# Create and change to a clean scratch directory.
rm -rf $BAKDIR
mkdir  $BAKDIR
if [ $? -ne 0 ]; then
  dlg_msg "Error: Cannot create directory '$BAKDIR'."
  exit 1
fi

dlg_msg "Now you will be asked for the backup file." "By default this is named emr_backup.tar, although you may have saved it as something else."

LOOKING=1
while [ $LOOKING -eq 1 ]; do
  dlg_fselect "Enter path/name of backup file"
  TARFILE=$RESULT
  dlg_blank_line
  if [ ! -f $TARFILE ]; then
    dlg_msg "Error: '$TARFILE' is not found or is not a file."
  else
    # Extract the backup tarball into the scratch directory.
    dlg_info "Extracting $TARFILE ..."
    cd $BAKDIR
    tar -xf $TARFILE
    if [ $? -ne 0 ]; then
      dlg_msg "Error: tar could not extract '$TARFILE'."
    else
      LOOKING=0
    fi
  fi
done

# Extract the OpenEMR web directory tree.
dlg_info "Extracting $BAKDIR/openemr.tar.gz ..."
mkdir openemr
cd openemr
tar zxf ../openemr.tar.gz
if [ $? -ne 0 ]; then
  dlg_msg "Error: tar could not extract '$BAKDIR/openemr.tar.gz'."
  exit 1
fi

OEDIR=/var/www/openemr

# Get the Site ID, it should be the only site backed up.
SITEID=`ls -1 sites | head -n 1`

# Get various parameters from the extracted files.
OEDBNAME=`grep '^\$dbase' sites/$SITEID/sqlconf.php | cut -d \' -f 2 | cut -d \" -f 2`
OEDBUSER=`grep '^\$login' sites/$SITEID/sqlconf.php | cut -d \' -f 2 | cut -d \" -f 2`
OEDBPASS=`grep '^\$pass'  sites/$SITEID/sqlconf.php | cut -d \' -f 2 | cut -d \" -f 2`

dlg_yesno "Do you want to specify site ID, locations or database names for the restore?"

CHANGES=$RESULT
OLDSITEID=$SITEID

dlg_blank_line

if [ $CHANGES -gt 0 ]; then
  dlg_msg "Current values are shown in [brackets]. Just hit Enter to leave them as-is."
  dlg_input "Site ID [$SITEID]? "
  if [ ! -z "$RESULT" ]; then SITEID="$RESULT"; fi
  dlg_input "OpenEMR database name [$OEDBNAME]? "
  if [ ! -z "$RESULT" ]; then OEDBNAME="$RESULT"; fi
  dlg_input "OpenEMR database user [$OEDBUSER]? "
  if [ ! -z "$RESULT" ]; then OEDBUSER="$RESULT"; fi
  dlg_input "OpenEMR database password [$OEDBPASS]? "
  if [ ! -z "$RESULT" ]; then OEDBPASS="$RESULT"; fi
  OLDOEDIR="$OEDIR"
  dlg_input "New OpenEMR web directory [$OEDIR]? "
  if [ ! -z "$RESULT" ]; then OEDIR="$RESULT"; fi
  #
fi

# The following sanity checks are an attempt to avoid disastrous results
# from mistakes in entry of directory path names.

TRASH=`expr "$OEDIR" : "[/]"`
if [ $TRASH -ne 1 ]; then
  dlg_msg "Error: The OpenEMR directory path '$OEDIR' does not start with '/'."
  exit 1
fi
if [ -e "$OEDIR" -a ! -e "$OEDIR/interface/globals.php" ]; then
  dlg_msg "Error: $OEDIR already exists but does not look like an OpenEMR directory." "If you are really sure you want to replace it, please remove it first."
  exit 1
fi

if [ -e "$OEDIR" -a ! -e "$OEDIR/sites" ]; then
  dlg_msg "Error: Directory '$OEDIR/sites' is missing - old release needs removal?"
  exit 1
fi

if [ -e "$OEDIR/sites/$SITEID" ]; then
  dlg_msg "Error: Site '$SITEID' already exists in '$OEDIR/sites'."
  exit 1
fi

COLLATE="utf8_general_ci"
dlg_msg "If you have a particular requirement for the UTF-8 collation to use, " \
  "then please specify it here.  Hit Enter to accept the default '$COLLATE'." \
  "Enter 'none' if you do not want UTF-8."
dlg_input "UTF-8 collation [$COLLATE]? "
if [ ! -z "$RESULT" ]; then COLLATE="$RESULT"; fi
TRASH=`expr "$COLLATE" : "[uU]"`
if [ $TRASH -ne 1 ]; then
  COLLATE=""
fi

# Ask the user to do final sanity checking.
#
MARGS="\"Your Site ID will be '$SITEID'.\""
if [ -e "$OEDIR" ]; then
  MARGS="$MARGS \"Only site-specific files will be restored to '$OEDIR/sites/$SITEID' in the existing OpenEMR web directory.\""
else
  MARGS="$MARGS \"I will install a new OpenEMR web directory '$OEDIR' from the backup.\""
fi
MARGS="$MARGS \"I will restore the OpenEMR database backup to the MySQL database '$OEDBNAME'.\""
MARGS="$MARGS \"The OpenEMR database user will be '$OEDBUSER' with password '$OEDBPASS'.\""
if [ -z "$COLLATE" ]; then
  MARGS="$MARGS \"MySQL will use its default character set and collation.\""
else
  MARGS="$MARGS \"MySQL will use character set 'utf8' with collation '$COLLATE'.\""
fi
MARGS="$MARGS \" \""
MARGS="$MARGS \"Please check the above very carefully!\""
MARGS="$MARGS \"Any existing databases and directories matching these names will be DESTROYED.\""
MARGS="$MARGS \"Do you wish to continue?\""
#
eval "dlg_yesno $MARGS"
if [ $RESULT -ne 1 ]; then
  exit 1
fi

dlg_blank_line

dlg_msg "In order to create MySQL databases and users on this computer, I will need to" \
        "log into MySQL as its 'root' user.  The next question asks for the MySQL root" \
        "user's password for this server, the one that you are restoring to.  This is"  \
        "a MySQL password, not a system login password.  It might be blank."
dlg_input 'Enter the password, if any, for the MySQL root user:'
MYROOTPASS="$RESULT"

dlg_blank_line

dlg_info "Dropping old OpenEMR database if it exists ..."
mysqladmin --password="$MYROOTPASS" --force drop $OEDBNAME 2> /dev/null

dlg_info "Restoring OpenEMR database ..."
cd $BAKDIR
gunzip openemr.sql.gz
if [ $? -ne 0 ]; then
  dlg_msg "Error: Could not decompress '$BAKDIR/openemr.sql.gz'."
  exit 1
fi

if [ -z $COLLATE ]; then
  TRASH="CREATE DATABASE $OEDBNAME"
else
  TRASH="CREATE DATABASE $OEDBNAME CHARACTER SET utf8 COLLATE $COLLATE"
fi
mysql --password="$MYROOTPASS" --execute "$TRASH"
if [ $? -ne 0 ]; then
  dlg_msg "Error creating MySQL database with '$TRASH'."
  exit 1
fi

mysql --password="$MYROOTPASS" --execute "CREATE USER '$OEDBUSER'@'localhost' IDENTIFIED BY '$OEDBPASS'" $OEDBNAME
mysql --password="$MYROOTPASS" --execute "GRANT ALL PRIVILEGES ON $OEDBNAME.* TO '$OEDBUSER'@'localhost' WITH GRANT OPTION" $OEDBNAME

mysql --user=$OEDBUSER --password="$OEDBPASS" $OEDBNAME < openemr.sql
if [ $? -ne 0 ]; then
  dlg_msg "Error: Restore to database '$OEDBNAME' failed."
  exit 1
fi

if [ -e "$OEDIR" ]; then
  dlg_info "Restoring site subdirectory ..."
  mv $BAKDIR/openemr/sites/$OLDSITEID $OEDIR/sites/$SITEID
  if [ $? -ne 0 ]; then
    dlg_msg "Error: Cannot create directory '$OEDIR/sites/$SITEID'."
    exit 1
  fi
else
  dlg_info "Restoring OpenEMR web directory tree ..."
  mv $BAKDIR/openemr $OEDIR
  if [ $? -ne 0 ]; then
    dlg_msg "Error: Cannot create directory '$OEDIR'."
    exit 1
  fi
fi
#
if [ $CHANGES -gt 0 ]; then
  dlg_info "Modifying $OEDIR/sites/$SITEID/sqlconf.php ..."
  cd $OEDIR/sites/$SITEID
  mv sqlconf.php sqlconf.php.old
  sed "s^dbase\s*=\s*['\"].*['\"]^dbase\t= '$OEDBNAME'^" sqlconf.php.old | \
  sed "s^login\s*=\s*['\"].*['\"]^login\t= '$OEDBUSER'^"                 | \
  sed "s^pass\s*=\s*['\"].*['\"]^pass\t= '$OEDBPASS'^" > sqlconf.php
fi

dlg_msg "All done."