#=================================================
# POSTGRES HELPERS
#=================================================

# Open a connection as a user
#
# example: ynh_psql_connect_as 'user' 'pass' <<< "UPDATE ...;"
# example: ynh_psql_connect_as 'user' 'pass' < /path/to/file.sql
#
# usage: ynh_psql_connect_as user pwd [db]
# | arg: user - the user name to connect as
# | arg: pwd - the user password
# | arg: db - the database to connect to
ynh_psql_connect_as() {
	user="$1"
	pwd="$2"
	db="$3"
	su --command="PGUSER=\"${user}\" PGPASSWORD=\"${pwd}\" psql \"${db}\"" postgres
}

# # Execute a command as root user
#
# usage: ynh_psql_execute_as_root sql [db]
# | arg: sql - the SQL command to execute
# | arg: db - the database to connect to
ynh_psql_execute_as_root () {
	sql="$1"
	su --command="psql" postgres <<< "$sql"
}

# Execute a command from a file as root user
#
# usage: ynh_psql_execute_file_as_root file [db]
# | arg: file - the file containing SQL commands
# | arg: db - the database to connect to
ynh_psql_execute_file_as_root() {
	file="$1"
	db="$2"
	su -c "psql $db" postgres < "$file"
}

# Create a database, an user and its password. Then store the password in the app's config
#
# After executing this helper, the password of the created database will be available in $db_pwd
# It will also be stored as "psqlpwd" into the app settings.
#
# usage: ynh_psql_setup_db user name [pwd]
# | arg: user - Owner of the database
# | arg: name - Name of the database
# | arg: pwd - Password of the database. If not given, a password will be generated
ynh_psql_setup_db () {
	db_user="$1"
	app="$1"
	db_name="$2"
	new_db_pwd=$(ynh_string_random)	# Generate a random password
	# If $3 is not given, use new_db_pwd instead for db_pwd.
	db_pwd="${3:-$new_db_pwd}"
	ynh_psql_create_db "$db_name" "$db_user" "$db_pwd"	# Create the database
	ynh_app_setting_set "$app" psqlpwd "$db_pwd"	# Store the password in the app's config
}

# Create a database and grant optionnaly privilegies to a user
#
# usage: ynh_psql_create_db db [user [pwd]]
# | arg: db - the database name to create
# | arg: user - the user to grant privilegies
# | arg: pwd  - the user password
ynh_psql_create_db() {
	db="$1"
	user="$2"
	pwd="$3"
	ynh_psql_create_user "$user" "$pwd"
	su --command="createdb --owner=\"${user}\" \"${db}\"" postgres
}

# Drop a database
#
# usage: ynh_psql_drop_db db user
# | arg: db - the database name to drop
# | arg: user - the user to drop
ynh_psql_remove_db() {
	db="$1"
	user="$2"
	su --command="dropdb \"${db}\"" postgres
	ynh_psql_drop_user "${user}"
}

# Dump a database
#
# example: ynh_psql_dump_db 'roundcube' > ./dump.sql
#
# usage: ynh_psql_dump_db db
# | arg: db - the database name to dump
# | ret: the psqldump output
ynh_psql_dump_db() {
	db="$1"
	su --command="pg_dump \"${db}\"" postgres
}


# Create a user
#
# usage: ynh_psql_create_user user pwd [host]
# | arg: user - the user name to create
ynh_psql_create_user() {
	user="$1"
	pwd="$2"
        su --command="psql -c\"CREATE USER ${user} WITH PASSWORD '${pwd}'\"" postgres
}

# Drop a user
#
# usage: ynh_psql_drop_user user
# | arg: user - the user name to drop
ynh_psql_drop_user() {
	user="$1"
	su --command="dropuser \"${user}\"" postgres
}


ynh_psql_test_if_first_run() {
	if [ -f /etc/yunohost/psql ];
	then
		echo "PostgreSQL is already installed, no need to create master password"
	else
		pgsql=$(ynh_string_random)
		pg_hba=""
		echo "$pgsql" >> /etc/yunohost/psql

		if [ -e /etc/postgresql/9.4/ ]
		then
			pg_hba=/etc/postgresql/9.4/main/pg_hba.conf
		elif [ -e /etc/postgresql/9.6/ ]
		then
			pg_hba=/etc/postgresql/9.6/main/pg_hba.conf
		else
			ynh_die "postgresql shoud be 9.4 or 9.6"
		fi

		systemctl start postgresql
                su --command="psql -c\"ALTER user postgres WITH PASSWORD '${pgsql}'\"" postgres
		# we can't use peer since YunoHost create users with nologin
		sed -i '/local\s*all\s*all\s*peer/i \
		local all all password' "$pg_hba"
		systemctl enable postgresql
		systemctl reload postgresql
	fi
}

#=================================================
# OTHERS HELPERS
#=================================================

# Read the value of a key in a ynh manifest file
#
# usage: ynh_read_manifest manifest key
# | arg: manifest - Path of the manifest to read
# | arg: key - Name of the key to find
ynh_read_manifest () {
	manifest="$1"
	key="$2"
	python3 -c "import sys, json;print(json.load(open('$manifest'))['$key'])"
}

# Read the upstream version from the manifest 
# The version number in the manifest is defined by <upstreamversion>~ynh<packageversion>
# For example : 4.3-2~ynh3
# This include the number before ~ynh
# In the last example it return 4.3-2
#
# usage: ynh_app_upstream_version
ynh_app_upstream_version () {
    manifest_path="../manifest.json"
    if [ ! -e "$manifest_path" ]; then
        manifest_path="../settings/manifest.json"	# Into the restore script, the manifest is not at the same place
    fi
    version_key=$(ynh_read_manifest "$manifest_path" "version")
    echo "${version_key/~ynh*/}"
}

# Read package version from the manifest
# The version number in the manifest is defined by <upstreamversion>~ynh<packageversion>
# For example : 4.3-2~ynh3
# This include the number after ~ynh
# In the last example it return 3
#
# usage: ynh_app_package_version
ynh_app_package_version () {
    manifest_path="../manifest.json"
    if [ ! -e "$manifest_path" ]; then
        manifest_path="../settings/manifest.json"	# Into the restore script, the manifest is not at the same place
    fi
    version_key=$(ynh_read_manifest "$manifest_path" "version")
    echo "${version_key/*~ynh/}"
}