<?php
/**
 * This file provides the BusinessAdmin class
 *
 * @author Camil Staps
 *
 * BusinessAdmin: administrative software for small companies
 * Copyright (C) 2015 Camil Staps (ViviSoft)
 *
 * 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 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 General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

/**
 * Provides basic functions like adding elements to the database
 */
class BusinessAdmin {
	//------------------------------------------------------------------------------
	// Getters and setters
	//------------------------------------------------------------------------------

	/**
	 * Get all user ids
	 *
	 * @see BusinessAdmin::getUsers()         This funtion returns instances of the user class instead of just the ids
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 * @param string[] $where                 An array of WHERE clauses that will be AND-ed into a prepared statement
	 * @param mixed[] $variables              An array of variables that should go into the prepared statement
	 *
	 * @throws PDOException                   Is something went wrong with the database
	 *
	 * @return int[]                          The ids
	 */
	public static function getUserIds($pdo, $where = [], $variables = []) {
		$ids = [];
		$users = $pdo->prepare("SELECT `id` FROM `".constants::db_prefix."user`" . ((count($where) > 0) ? (" WHERE (" . implode(') AND (', $where) . ")") : ""));
		$users->execute($variables);
		$users = $users->fetchAll(PDO::FETCH_ASSOC);
		foreach ($users as $user) {
			$ids[] = $user['id'];
		}
		return $ids;
	}

	/**
	 * Get all users
	 *
	 * @see BusinessAdmin::getUserIds()       This function returns just the ids of the users, and not instances of the user class
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 * @param string[] $where                 An array of WHERE clauses that will be AND-ed into a prepared statement
	 * @param mixed[] $variables              An array of variables that should go into the prepared statement
	 *
	 * @throws PDOException                   If something went wrong with the database
	 *
	 * @return user[]                         An array indexed by id of instances of the user class
	 */
	public static function getUsers($pdo, $where = [], $variables = []) {
		$ids = self::getUserIds($pdo, $where, $variables);
		$users = [];
		foreach ($ids as $id) {
			$users[$id] = new user($pdo, $id);
		}
		return $users;
	}

	/**
	 * Get all client ids
	 *
	 * @see BusinessAdmin::getClients()       This funtion returns instances of the client class instead of just the ids
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 *
	 * @throws PDOException                   If something went wrong with the database
	 *
	 * @return int[]                          The ids
	 */
	public static function getClientIds($pdo) {
		$ids = array();
		$clients = $pdo->query("SELECT `id` FROM `".constants::db_prefix."client`")->fetchAll(PDO::FETCH_ASSOC);
		foreach ($clients as $client) {
			$ids[] = $client['id'];
		}
		return $ids;
	}

	/**
	 * Get all clients
	 *
	 * @see BusinessAdmin::getClientIds()     This function returns just the ids of the clients, and not instances of the client class
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 *
	 * @throws PDOException                   If something went wrong with the database
	 *
	 * @return client[]                       An array indexed by id of instances of the client class
	 */
	public static function getClients($pdo) {
		$ids = self::getClientIds($pdo);
		$clients = array();
		foreach ($ids as $id) {
			$clients[$id] = new client($pdo, $id);
		}
		return $clients;
	}

	/**
	 * Get all contact ids
	 *
	 * @see BusinessAdmin::getContacts()      This funtion returns instances of the contact class instead of just the ids
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 *
	 * @throws PDOException                   Is something went wrong with the database
	 *
	 * @return int[]                          The ids
	 */
	public static function getContactIds($pdo) {
		$ids = array();
		$contacts = $pdo->query("SELECT `id` FROM `".constants::db_prefix."contact`")->fetchAll(PDO::FETCH_ASSOC);
		foreach ($contacts as $contact) {
			$ids[] = $contact['id'];
		}
		return $ids;
	}

	/**
	 * Get all contacts
	 *
	 * @see BusinessAdmin::getContactIds()    This function returns just the ids of the contacts, and not instances of the contact class
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 *
	 * @throws PDOException                   If something went wrong with the database
	 *
	 * @return contact[]                      An array indexed by id of instances of the contact class
	 */
	public static function getContacts($pdo) {
		$ids = self::getContactIds($pdo);
		$contacts = array();
		foreach ($ids as $id) {
			$contacts[$id] = new contact($pdo, $id);
		}
		return $contacts;
	}

	/**
	 * Get all offer ids
	 *
	 * @see BusinessAdmin::getOffers()        This funtion returns instances of the offer class instead of just the ids
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 * @param string[] $where                 An array of WHERE clauses that will be AND-ed
	 *
	 * @throws PDOException                   Is something went wrong with the database
	 *
	 * @return int[]                          The ids
	 */
	public static function getOfferIds($pdo, $where = array()) {
		$ids = array();
		$offers = $pdo->query("SELECT `id` FROM `".constants::db_prefix."offer`" . ((count($where) > 0) ? (" WHERE (" . implode(') AND (', $where) . ")") : ""))->fetchAll(PDO::FETCH_ASSOC);
		foreach ($offers as $offer) {
			$ids[] = $offer['id'];
		}
		return $ids;
	}

	/**
	 * Get all offers
	 *
	 * @see BusinessAdmin::getOfferIds()      This function returns just the ids of the offers, and not instances of the offer class
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 * @param string[] $where                 An array of WHERE clauses that will be AND-ed
	 *
	 * @throws PDOException                   If something went wrong with the database
	 *
	 * @return offer[]                        An array indexed by id of instances of the offer class
	 */
	public static function getOffers($pdo, $where = array()) {
		$ids = self::getOfferIds($pdo, $where);
		$offers = array();
		foreach ($ids as $id) {
			$offers[$id] = new offer($pdo, $id);
		}
		return $offers;
	}

	/**
	 * Get all assignment ids
	 *
	 * @see BusinessAdmin::getAssignments()   This funtion returns instances of the assignment class instead of just the ids
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 * @param string[] $where                 An array of WHERE clauses that will be AND-ed
	 *
	 * @throws PDOException                   Is something went wrong with the database
	 *
	 * @return int[]                          The ids
	 */
	public static function getAssignmentIds($pdo, $where = array()) {
		$ids = array();
		$assignments = $pdo->query("SELECT `id` FROM `".constants::db_prefix."assignment`" . ((count($where) > 0) ? (" WHERE (" . implode(') AND (', $where) . ")") : ""))->fetchAll(PDO::FETCH_ASSOC);
		foreach ($assignments as $assignment) {
			$ids[] = $assignment['id'];
		}
		return $ids;
	}

	/**
	 * Get all assignments
	 *
	 * @see BusinessAdmin::getAssignmentIds() This function returns just the ids of the assignments, and not instances of the assignment class
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 * @param string[] $where                 An array of WHERE clauses that will be AND-ed
	 *
	 * @throws PDOException                   If something went wrong with the database
	 *
	 * @return assignment[]                   An array indexed by id of instances of the assignment class
	 */
	public static function getAssignments($pdo, $where = array()) {
		$ids = self::getAssignmentIds($pdo, $where);
		$assignments = array();
		foreach ($ids as $id) {
			$assignments[$id] = new assignment($pdo, $id);
		}
		return $assignments;
	}

	/**
	 * Get all discount ids
	 *
	 * @see BusinessAdmin::getDiscounts()     This funtion returns instances of the discount class instead of just the ids
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 * @param string[] $where                 An array of WHERE clauses that will be AND-ed
	 *
	 * @throws PDOException                   Is something went wrong with the database
	 *
	 * @return int[]                          The ids
	 */
	public static function getDiscountIds($pdo, $where = array()) {
		$ids = array();
		$discounts = $pdo->query("SELECT `id` FROM `".constants::db_prefix."discount`" . ((count($where) > 0) ? (" WHERE (" . implode(') AND (', $where) . ")") : ""))->fetchAll(PDO::FETCH_ASSOC);
		foreach ($discounts as $discount) {
			$ids[] = $discount['id'];
		}
		return $ids;
	}

	/**
	 * Get all discounts
	 *
	 * @see BusinessAdmin::getDiscountIds()   This function returns just the ids of the discounts, and not instances of the discount class
	 *
	 * @param PDO $pdo                        The PDO class for database connection
	 * @param string[] $where                 An array of WHERE clauses that will be AND-ed
	 *
	 * @throws PDOException                   If something went wrong with the database
	 *
	 * @return discount[]                     An array indexed by id of instances of the discount class
	 */
	public static function getDiscounts($pdo, $where = array()) {
		$ids = self::getDiscountIds($pdo, $where);
		$discounts = array();
		foreach ($ids as $id) {
			$discounts[$id] = new discount($pdo, $id);
		}
		return $discounts;
	}

	//------------------------------------------------------------------------------
	// Other functions
	//------------------------------------------------------------------------------

	/**
	 * Create a new client
	 *
	 * @param PDO $pdo                        The database connection
	 * @param string $name                    The name for the new client
	 *
	 * @throws PDOException                   If something went wrong with the database
	 *
	 * @return client|bool                    A new instance of the client object, or false on failure
	 */
	public static function createClient($pdo, $name) {
		$stmt = $pdo->prepare("INSERT INTO `".constants::db_prefix."client` (`name`) VALUES (?)");
		$stmt->execute(array($name));
		if ($stmt->rowCount() == 1) {
			return new client($pdo, $pdo->lastInsertId());
		} else {
			return false;
		}
	}

	/**
	 * Create a new file
	 *
	 * @param PDO $pdo                        The database connection
	 * @param string $filename                The desired filename
	 *
	 * @throws PDOException                   If something went wrong with the database
	 * @throws Exception                      If the file could not be created (due to permissions, file existed already, etc.), or the database record couldn't be added
	 *
	 * @return file                           A new instance of the file object
	 */
	public static function createFile($pdo, $filename) {
		// Check for file existence
		if (file_exists(constants::files_folder . $filename)) {
			throw new Exception("$filename already exists.");
		}

		// Try to create the file
		if (file_put_contents(constants::files_folder . $filename, '') === false) {
			throw new Exception("$filename could not be created. Check the permissions.");
		}

		$stmt = $pdo->prepare("INSERT INTO `".constants::db_prefix."file` (`filename`) VALUES (?)");
		$stmt->execute(array($filename));
		if ($stmt->rowCount() == 1) {
			return new file($pdo, $pdo->lastInsertId());
		} else {
			unlink(constants::files_folder . $filename);
			throw new Exception("$filename could not be added to the database");
		}
	}

	/**
	 * Create a new user
	 *
	 * @param PDO $pdo                        The database connection
	 * @param string $username                The username for the new user
	 * @param string $password                The password for the new user
	 *
	 * @throws PDOException                   If something went wrong with the database
	 *
	 * @return user|bool                      A new instance of the user object, or false on failure
	 */
	public static function createUser($pdo, $username, $password) {
		$stmt = $pdo->prepare("INSERT INTO `".constants::db_prefix."user` (`username`, `password`) VALUES (?,?)");
		$stmt->execute([$username, user::hash($password)]);
		if ($stmt->rowCount() == 1) {
			return new user($pdo, $pdo->lastInsertId());
		} else {
			return false;
		}
	}

	/**
	 * Format a date nicely
	 *
	 * @todo implement $relatively = true
	 *
	 * @param int $timestamp                  The UNIX timestamp to format
	 * @param bool $with_time                 If false, only the date is returned; if false, also the time
	 * @param bool $full_date                 If true, a year will be outputted even if the date is in the current year
	 * @param bool $relatively                Whether or not to show the date relatively (e.g. '1 day ago') (NOT IMPLEMENTED YET)
	 *
	 * @return string The formatted date
	 */
	public static function formatDate($timestamp, $with_time = true, $full_date = false, $relatively = false) {
		$output = '';
		if (date('Y', $timestamp) == 1970) {
			return 'never';
		}
		if (date('d/m/Y') == date('d/m/Y', $timestamp)) {
			return 'today';
		}
		if (date('Y') != date('Y', $timestamp) || $full_date) {
			$output .= date('Y-', $timestamp);
		}
		if (date('d/m/Y') != date('d/m/Y', $timestamp) || $full_date) {
			$output .= date('m-d', $timestamp);
		}
		if ($with_time) {
			$output .= date(' H:i', $timestamp);
		}

		return $output;
	}
}