#!/bin/bash

# Exit on error.
set -e

# Command we pipe to execute the sql.
sql_cmd='mariadb -u root'

# SQL to create the database.
sql_create_db="CREATE DATABASE \`%s\`;"

# SQL to create user.
sql_create_user="CREATE USER IF NOT EXISTS '%s'@'%s' IDENTIFIED BY '%s';"

# SQL grant usage.
sql_grant_usage="GRANT USAGE ON *.* TO '%s'@'%s' IDENTIFIED BY '%s';"

# SQL grant on users database.
sql_grant_on_db="GRANT ALL privileges ON \`%s\`.* TO '%s'@'%s';"

# SQL flush
sql_flush='FLUSH PRIVILEGES;'

DB_HOST='localhost'
DB_USER=""
DB_NAME=""
DB_PASS=""
DB_PASS_REP=""

new_user() {
    
    printf '(new) database user?\n' && read -t 120 DB_USER;

    [[ ! "${DB_USER}" =~ ^[A-Za-z]{1}[A-Za-z0-9\_\-]+$ ]] && \
        printf 'min 2 chars, A-z0-9_- allowed.. ' && new_user

    return 0
}

new_db_name() {
    
    printf '(new) database name?\n' && read -t 120 DB_NAME;

    [[ ! "${DB_NAME}" =~ ^[A-Za-z]{1}[A-Za-z0-9\_\-]+$ ]] && \
        printf 'min 2 chars, A-z0-9_- allowed.. ' && new_db_name

    return 0
}

new_pass() {
    
    printf 'password? (input hidden)\n' && read -st 120 DB_PASS;
    printf 'password again?\n' && read -st 120 DB_PASS_REP;

    [[ -z "$DB_PASS" ]] || [[ -z "$DB_PASS_REP" ]] && new_pass
    [[ ! "$DB_PASS" == "$DB_PASS_REP" ]] && \
        printf 'passwords do not match.. ' && new_pass

    return 0

}

# Note: set -e requires the functions to return 0.
new_db_name
new_user
new_pass

# Create database.
printf "$sql_create_db" "$DB_NAME" | $sql_cmd;

# The user.
printf "$sql_create_user" "$DB_USER" "${DB_HOST:-NONE}" \
    "$DB_PASS" | $sql_cmd;

# The grants.
printf "$sql_grant_usage" "$DB_USER" "${DB_HOST:-NONE}" \
    "$DB_PASS" | $sql_cmd;

printf "$sql_grant_on_db" "$DB_NAME" "${DB_USER:-NONE}" \
    "${DB_HOST:-NONE}" | $sql_cmd;

printf "$sql_flush" | $sql_cmd;