#!/bin/bash

#=================================================
# GENERIC START
#=================================================
# IMPORT GENERIC HELPERS
#=================================================

source /usr/share/yunohost/helpers

#=================================================
# LOAD SETTINGS
#=================================================

app=$YNH_APP_INSTANCE_NAME

domain=$(ynh_app_setting_get $app domain)
path_url=$(ynh_app_setting_get $app path)
is_public=$(ynh_app_setting_get $app is_public)
final_path=$(ynh_app_setting_get $app final_path)
db_name=$(ynh_app_setting_get $app db_name)
with_mysql=$(ynh_app_setting_get $app with_mysql)
password=$(ynh_app_setting_get $app password)
user=$(ynh_app_setting_get $app user)

#=================================================
# CHECK IF THE UPGRADE CAN BE AUTOMATED
#=================================================

([[ -n "$with_mysql" ]] && [[ -n "$password" ]] && [[ -n "$user" ]]) \
  || ynh_die "The app changed and can not be automatically upgraded. \
You will have to manually upgrade it following these instructions: \
https://github.com/YunoHost-Apps/my_webapp_ynh#upgrade"

#=================================================
# ENSURE DOWNWARD COMPATIBILITY
#=================================================

# If db_name doesn't exist, create it
if [ -z $db_name ]; then
	db_name=$(ynh_sanitize_dbid $app)
	ynh_app_setting_set $app db_name $db_name
fi

# If final_path doesn't exist, create it
if [ -z $final_path ]; then
	final_path=/var/www/$app
	ynh_app_setting_set $app final_path $final_path
fi

#=================================================
# BACKUP BEFORE UPGRADE THEN ACTIVE TRAP
#=================================================

ynh_backup_before_upgrade	# Backup the current version of the app
ynh_clean_setup () {
	ynh_restore_upgradebackup	# restore it if the upgrade fails
}
ynh_abort_if_errors	# Exit if an error occurs during the execution of the script

#=================================================
# CHECK THE PATH
#=================================================

# Normalize the URL path syntax
path_url=$(ynh_normalize_url_path $path_url)

#=================================================
# STANDARD UPGRADE STEPS
#=================================================

# Check if a config file was modified
is_checksum_different () {
    local file=$1
    local checksum_setting_name=checksum_${file//[\/ ]/_}	# Replace all '/' and ' ' by '_'
    local checksum_value=$(ynh_app_setting_get $app $checksum_setting_name)
    if [ -n "$checksum_value" ]
    then	# Proceed only if a value was stored into the app settings
      if ! echo "$checksum_value $file" | sudo md5sum -c --status
      then	# If the checksum is now different
        echo "File $file has been manually modified since the installation or last upgrade. So it will not be replaced." >&2
        echo "1"
      else
        echo "0"
      fi
    else
      echo "0"
    fi
}

#=================================================
# NGINX CONFIGURATION
#=================================================

if [ $(is_checksum_different "/etc/nginx/conf.d/$domain.d/$app.conf") -eq 0 ]
then
    # Create a dedicated nginx config
    ynh_add_nginx_config
fi

#=================================================
# CREATE DEDICATED USER
#=================================================

# Create a standard user (not a system user for sftp)
ynh_system_user_exists "$user" || \
    useradd -d "$final_path" -M --user-group "$user"
# Add the password to this user
chpasswd <<< "${user}:${password}"

# Change the user group for previous my_webapp install script
groupadd -f "$user"
usermod -g "$user" "$user"

#=================================================
# PHP-FPM CONFIGURATION
#=================================================

if [ $(is_checksum_different "/etc/php5/fpm/pool.d/$app.conf") -eq 0 ]
then
    # Create a dedicated php-fpm config
    ynh_replace_string "__USER__" "$user" "../conf/php-fpm.conf"
    ynh_add_fpm_config
fi

#=================================================
# SPECIFIC UPGRADE
#=================================================
# CONFIGURE SSH
#=================================================

# Remove the previous config for upgrading it
sudo sed -i "/##-> ${app}/,/##<- ${app}/d" /etc/ssh/sshd_config
# Harden SSH connection for the user
echo "##-> ${app}
# Hardening user connection
Match User ${user}
  ChrootDirectory %h
  ForceCommand internal-sftp
  AllowTcpForwarding no
  PermitTunnel no
  X11Forwarding no
##<- ${app}" | tee -a /etc/ssh/sshd_config >/dev/null

systemctl reload ssh

#=================================================
# GENERIC FINALIZATION
#=================================================
# SECURE FILES AND DIRECTORIES
#=================================================

# Home directory of the user needs to be owned by root to allow
# SFTP connections
chown root: "$final_path"

#=================================================
# SETUP SSOWAT
#=================================================

# Make app public if necessary
if [ $is_public -eq 1 ]
then
	ynh_app_setting_set $app skipped_uris "/"
fi

#=================================================
# RELOAD NGINX
#=================================================

systemctl reload nginx