Merge pull request #1 from Syndamia/dev v0.1

Implemented main functionality

1 files changed, 176 insertions, 0 deletions

diff --git a/src/models/DB.php b/src/models/DB.php
new file mode 100644
index 0000000..8174831
--- /dev/null
+++ b/src/models/DB.php
@@ -0,0 +1,176 @@
+<?php
+/**
+ * The model that has the database functionality. DO NOT instantiate this class! If you need an instance, extend the DBModel class!
+ */
+class DB {
+	private static $servername = "localhost";
+	private static $username = "root";
+	private static $password = "password";
+	private static $dbname = "devrix_job_board";
+
+	public const STRING_TYPE = "VARCHAR(100)";
+	public const FLOAT_TYPE = "DOUBLE(16,4)";
+	public const INTEGER_TYPE = "INT";
+
+	private PDO $connection;
+
+	function __construct() {
+		// Try to connect
+		try {
+			$this->connection = new PDO("mysql:host=" . self::$servername, self::$username, self::$password);
+			$this->connection->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
+		}
+		catch (PDOException $e) {
+			echo "[DB Exception]: " . $e->getMessage();
+		}
+
+		// Make sure the actual db exists
+		$createDBQuery = "CREATE DATABASE IF NOT EXISTS " . self::$dbname . ";";
+
+		$this->connection->exec($createDBQuery);
+
+		// Connect to the actual database
+		$this->connection->exec("USE " . self::$dbname);
+	}
+
+	/**
+	 * @return string
+	 */
+	static function genFK(string $currentColumn, string $foreignTable, string $foreignColumn) {
+		return "CONSTRAINT fk_{$currentColumn}_{$foreignTable} FOREIGN KEY ({$currentColumn}) REFERENCES {$foreignTable}($foreignColumn)";
+	}
+
+	/* Create */
+
+	/**
+	 * Creates a table, with the given name and given column information.
+	 * **WARNING**: The method also creates an auto-incremented int id column, **DO NOT** specify it!
+	 *
+	 * @param string[] $columns
+	 * Represents the column information. Each value must be like: "column_name data_type", where the data_type should be taken
+	 * from the constant values of DB class.
+	 * Example value: array("first_name " . DB::STRING_TYPE, "age " . DB::INTEGER_TYPE, "income " . DB::FLOAT_TYPE)
+	 *
+	 * @param string[] $foreignKeys - OPTIONAL
+	 * Represents the foreign keys. All foreign keys **MUST** be generated the the static DB method genFK.
+	 * Example value: array(DB::genFK("jobId", "jobs", "id"), DB::genFK("cityId", "cities", "id"))
+	 */
+	function createTable(string $tableName, array $columns, array $foreignKeys = null) {
+		$query = "CREATE TABLE IF NOT EXISTS {$tableName}(
+				  id INT NOT NULL AUTO_INCREMENT, ";
+
+		foreach ($columns as $column) {
+			$query .= "{$column}, ";
+		}
+
+		$query .= "PRIMARY KEY (id), ";
+
+		foreach ($foreignKeys as $fk) {
+			$query .= "{$fk}, ";
+		}
+
+		$query = rtrim($query, ", ");
+		$query .= ");";
+
+		try {
+			$this->connection->exec($query);
+		}
+		catch (PDOException $e) {
+			echo "[DB Exception]: " . $e->getMessage();
+		}
+	}
+
+	/**
+	 * Inserts a value in a given table.
+	 *
+	 * @param string[] $values
+	 * Represents the data that should be inserted. The values should be ordered the same way the table columns are ordered.
+	 * Example: "John", 20, 2000.3
+	 * **WARNING**: DO NOT insert the id value
+	 */
+	function insertValue(string $tableName, ...$values) {
+		$query = "INSERT INTO {$tableName} VALUES(NULL, ";
+
+		foreach($values as $value) {
+			if (gettype($value) == "string") {
+				$query .= "'{$value}', ";
+			}
+			else {
+				$query .= "{$value}, ";
+			}
+		}
+		$query = rtrim($query, ", ");
+
+		$query .= ");";
+
+		try {
+			$this->connection->exec($query);
+		}
+		catch (PDOException $e) {
+			echo "[DB Exception]: " . $e->getMessage();
+		}
+	}
+
+	/* Read */
+
+	/**
+	 * Returns the next value that has the given id.
+	 */
+	function getById(string $tableName, int $id) {
+		$sth = $this->connection->prepare("SELECT * FROM `{$tableName}` WHERE id = {$id}");
+		$sth->execute();
+
+		return $sth->fetch(PDO::FETCH_OBJ);
+	}
+
+	/**
+	 * Returns all values inside a table.
+	 */
+	function getAllValues(string $tableName) {
+		$sth = $this->connection->prepare("SELECT * FROM `{$tableName}`");
+		$sth->execute();
+
+		return $sth->fetchAll(PDO::FETCH_OBJ);
+	}
+
+	/* Update */
+
+	/**
+	 * Updates the value with the given id inside the specified table.
+	 *
+	 * @param string[] $values
+	 * Represents the data that should be updated. There should always be an even amount of data, where you alternate the column name and column value.
+	 * Example: "first_name", "John", "age", 20, "income", 2000.3
+	 */
+	function updateById(string $tableName, int $id, ...$values) {
+		$query = "UPDATE {$tableName} SET ";
+
+		for ($i = 0; $i < sizeof($values); $i += 2) {
+			$query .= "{$values[$i]} = " . (gettype($values[$i+1]) == "string" ? "'{$values[$i+1]}'" : $values[$i+1]) . ", ";
+		}
+		$query = rtrim($query, ", ");
+
+		$query .= " WHERE id = {$id};";
+
+		try {
+			$this->connection->exec($query);
+		}
+		catch (PDOException $e) {
+			echo "[DB Exception]: " . $e->getMessage();
+		}
+	}
+
+	/* Delete */
+
+	/**
+	 * Deletes the value with the given id inside the given table.
+	 */
+	function deleteById(string $tableName, int $id) {
+		try {
+			$this->connection->exec("DELETE FROM {$tableName} WHERE id = {$id}");
+		}
+		catch (PDOException $e) {
+			echo "[DB Exception]: " . $e->getMessage();
+		}
+	}
+}