#!/bin/bash
#  _____               _           _
# |   __|___ ___ ___ _| |___ _____| |_ ___ ___ ___
# |   __|  _| -_| -_| . | . |     | . | . |   | -_|
# |__|  |_| |___|___|___|___|_|_|_|___|___|_|_|___|
#
#                              Freedom in the Cloud
#
# postgresql database functions
#
# License
# =======
#
# Copyright (C) 2017-2018 Bob Mottram <bob@freedombone.net>
#
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

# Set this when calling backup and restore commands
USE_POSTGRESQL=
POSTGRESQL_PACKAGES='postgresql-9.6 postgresql-contrib-9.6 postgresql-client'
POSTGRESQL_VERSION=9.6

function turn_off_postgresql_logging {
    if [ ! -f /etc/postgresql/$POSTGRESQL_VERSION/main/postgresql.conf ]; then
        return
    fi
    sed -i 's|#log_destination|log_destination|g' /etc/postgresql/$POSTGRESQL_VERSION/main/postgresql.conf
    sed -i "s|log_destination.*|log_destination = 'syslog'|g" /etc/postgresql/$POSTGRESQL_VERSION/main/postgresql.conf
    if [ -d /var/log/postgresql ]; then
        $REMOVE_FILES_COMMAND /var/log/postgresql/*
    fi
}

function turn_on_postgresql_logging {
    if [ ! -f /etc/postgresql/$POSTGRESQL_VERSION/main/postgresql.conf ]; then
        return
    fi
    sed -i 's|log_destination|#log_destination|g' /etc/postgresql/$POSTGRESQL_VERSION/main/postgresql.conf
    sed -i "s|log_destination.*|log_destination = 'stderr'|g" /etc/postgresql/$POSTGRESQL_VERSION/main/postgresql.conf
}

function store_original_postgresql_password {
    if [ ! -f /root/.postgresqloriginal ]; then
        echo $'Storing original postgresql password'
        ORIGINAL_POSTGRESQL_PASSWORD=$("${PROJECT_NAME}-pass" -u root -a postgresql)
        # We can store this in plaintext because it will soon be of historical interest only
        echo -n "$ORIGINAL_POSTGRESQL_PASSWORD" > /root/.postgresqloriginal
    fi
}

function get_postgresql_password {
    POSTGRESQL_PASSWORD=$("${PROJECT_NAME}-pass" -u root -a postgresql)
    if [[ "$POSTGRESQL_PASSWORD" == *'failed'* ]]; then
        echo $'Could not obtain postgresql password'
        exit 7835272
    fi
}

function image_install_postgresql {
    # shellcheck disable=SC2154,SC2086
    chroot "$rootdir" apt-get -yq install $POSTGRESQL_PACKAGES

    if [ ! -d "$rootdir/etc/postgresql" ]; then
        echo $"ERROR: postgresql does not appear to have installed."
        exit 78352
    fi

    if [ ! -f "$rootdir/usr/bin/psql" ]; then
        echo $"ERROR: psql command does not appear to have installed."
        exit 835290
    fi
}

function install_postgresql {
    if [[ $VARIANT == "mesh"* ]]; then
        image_install_postgresql
        return
    fi

    if [[ $(is_completed "${FUNCNAME[0]}") == "1" ]]; then
        return
    fi

    function_check get_postgresql_password
    get_postgresql_password
    if [ ! "$POSTGRESQL_PASSWORD" ]; then
        if [ -f "$IMAGE_PASSWORD_FILE" ]; then
            POSTGRESQL_PASSWORD="$(printf "%s" "$(cat "$IMAGE_PASSWORD_FILE")")"
        else
            POSTGRESQL_PASSWORD="$(create_password "${MINIMUM_PASSWORD_LENGTH}")"
        fi
    fi
    "${PROJECT_NAME}-pass" -u root -a postgresql -p "$POSTGRESQL_PASSWORD"

    # shellcheck disable=SC2086
    apt-get -yq install $POSTGRESQL_PACKAGES
    apt-get -yq remove --purge apache2-bin*
    if [ -d /etc/apache2 ]; then
        rm -rf /etc/apache2
        echo $'Removed Apache installation after postgresql install'
    fi

    if [ ! -d /etc/postgresql ]; then
        echo $"ERROR: postgresql does not appear to have installed."
        exit 78352
    fi

    if [ ! -f /usr/bin/psql ]; then
        echo $"ERROR: psql command does not appear to have installed."
        exit 835290
    fi

    mark_completed "${FUNCNAME[0]}"
}

function add_postgresql_user {
    postgresql_username=$1
    postgresql_password=$2
    cd /etc/postgresql || exit 2468246
    if [[ "$3" != 'encrypt'* ]]; then
        sudo -u postgres psql -c "create user $postgresql_username password '$postgresql_password';"
    else
        sudo -u postgres psql -c "create user $postgresql_username;"
        sudo -u postgres psql -c "ALTER user $postgresql_username with encrypted password '$postgresql_password';"
    fi
}

function remove_postgresql_user {
    postgresql_username=$1
    cd /etc/postgresql || exit 24624624
    sudo -u postgres psql -c "drop user $postgresql_username"
}

function drop_database_postgresql {
    database_name="$1"
    database_owner_name="$2"
    cd /etc/postgresql || exit 2482468242
    sudo -u postgres psql -c "drop database $database_name"
    if [ ${#database_owner_name} -gt 0 ]; then
        sudo -u postgres psql -c "drop user $database_owner_name"
    fi
}

function run_system_query_postgresql {
    query=$1
    cd /etc/postgresql || exit 24624649846
    sudo -u postgres psql -c "$query"
}

function run_query_postgresql {
    database_name=$1
    database_query=$2
    cd /etc/postgresql || exit 2492464684
    sudo -u postgres psql -d "$database_name" -c "$database_query"
}

function run_query_postgresql_with_output {
    database_name=$1
    database_query=$2
    cd /etc/postgresql || exit 2482462846
    output=$(sudo -u postgres psql -d "$database_name" -c "$database_query")
    echo "$output"
}

function initialise_database_postgresql {
    database_name=$1
    database_file=$2
    cd /etc/postgresql || exit 239246992469
    # shellcheck disable=SC2024
    if ! sudo -u postgres psql "$database_name" < "$database_file"; then
        exit 7238525
    fi
}

function create_database_postgresql {
    app_name="$1"
    app_admin_password="$2"
    app_admin_username=$3
    if [ ! -d "$INSTALL_DIR" ]; then
        mkdir "$INSTALL_DIR"
    fi
    if [ ! "$app_admin_username" ]; then
        app_admin_username=${app_name}admin
    fi

    echo "create database ${app_name};
CREATE USER '$app_admin_username@localhost' IDENTIFIED BY '${app_admin_password}';
GRANT ALL PRIVILEGES ON ${app_name}.* TO '$app_admin_username@localhost';
flush privileges;
quit" > "$INSTALL_DIR/batch.sql"
    chmod 600 "$INSTALL_DIR/batch.sql"
    cd /etc/postgresql || exit 247284684
    sudo -u postgres psql -d "$database_name" --file="$INSTALL_DIR/batch.sql"
    rm "$INSTALL_DIR/batch.sql"
}

# NOTE: deliberately there is no "exit 0"