<?php


class DataBase
{
	const DEFAULT_DURATION = '+7 day';
	const OPTIONS_DURATION = array(
		'day' => '+1 day',
		'week' => '+7 day',
		'week2' => '+14 day',
		'month' => '+1 month'
	);
	const DEFAULT_SIZE = 3;

	private $db;

	public function __construct()
	{
		$this->init();
	}

	public function init()
	{
		require_once 'dbconfig.php';
		$dsn = 'pgsql:dbname=' . $dbname
			     . ';host=' . $host
			     . ';port=' . $port;
		try {
			$this->db = new PDO($dsn, $username, $password);
			$this->db->setAttribute(PDO::ATTR_ERRMODE, PDO::ERRMODE_EXCEPTION);
			$this->db->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);
		} catch (PDOException $e) {
			echo $e->getMessage();
			return null;
		}
	}

	public function isInit()
	{
		return isset($this->db);
	}

	public function buildTables()
	{
		$stmt = $this->db->prepare("
			CREATE TABLE IF NOT EXISTS clouds(
				id_cloud serial PRIMARY KEY,
				code     TEXT NOT NULL UNIQUE,
				size     INTEGER NOT NULL DEFAULT 3,
				text     TEXT,
				delete_t TIMESTAMP DEFAULT
					(CURRENT_TIMESTAMP + INTERVAL '" . self::DEFAULT_DURATION . "')
			);
		");
		$stmt->execute();
		$stmt = $this->db->prepare("
			CREATE TABLE IF NOT EXISTS words(
				id_word  serial PRIMARY KEY,
				word     TEXT NOT NULL,
				count    INT DEFAULT 1,
				cloud_id INT NOT NULL,
				FOREIGN KEY (cloud_id)
					REFERENCES clouds(id_cloud) ON UPDATE CASCADE
					ON DELETE CASCADE
			);
		");
		$stmt->execute();
	}

	public function addWord(string $cloud, string $word)
	{
		if (empty($word)) {
			return false;
		}
		$stmt = $this->db->prepare("
			SELECT *
			FROM   clouds
			WHERE  code = :id;
		");
		$stmt->bindValue(':id', $cloud, PDO::PARAM_STR);
		$stmt->execute();
		$cloudId = null;
		if ($data = $stmt->fetch()) {
			$cloudId = $data['id_cloud'];
		} else {
			return false;
		}
		$stmt = $this->db->prepare("
			SELECT *
			FROM   words
			WHERE  cloud_id = :cid
			AND    word = :w;
		");
		$stmt->bindValue(':cid', $cloudId, PDO::PARAM_INT);
		$stmt->bindValue(':w', $word, PDO::PARAM_STR);
		$stmt->execute();
		if ($data = $stmt->fetch()) {
			$wordId = $data['id_word'];
			$stmt = $this->db->prepare("
				UPDATE words
				SET    count = count + 1
				WHERE  id_word = :id;
			");
			$stmt->bindValue(':id', $wordId, PDO::PARAM_INT);
			$stmt->execute();
		} else {
			$stmt = $this->db->prepare("
				INSERT INTO words(word, cloud_id)
				VALUES           (:w, :cid);
			");
			$stmt->bindValue(':w', $word, PDO::PARAM_STR);
			$stmt->bindValue(':cid', $cloudId, PDO::PARAM_INT);
			$stmt->execute();
		}
	}
	public function getWordsList(string $id)
	{
		$stmt = $this->db->prepare("
			SELECT *
			FROM   words
			JOIN   clouds
			ON     words.cloud_id = clouds.id_cloud
			WHERE  code = :id;
		");
		$stmt->bindValue(':id', $id);
		$stmt->execute();
		$words  = [];
		$values = [];
		$total  = 0;
		$max    = 0;
		while ($data = $stmt->fetch()) {
			$words[] = array(
				'word' => $data['word'],
				'count' => $data['count'],
			);
			$values[] = $data['count'];
			$total += $data['count'];
			$max = max($max, $data['count']);
		}
		foreach ($words as $key => $word) {
			$words[$key]['relative'] = $word['count'] / $max;
			$words[$key]['percent'] = $word['count'] / $total * 100;
		}

		array_multisort($values, SORT_DESC, $words);
		return $words;
	}

	public function getWordsPercentage(string $id)
	{
		$words = $this->getWordsList($id);
		$total = 0;
		foreach ($words as $word) {
			$total += $word[1];
		}
		foreach ($words as $key => $word) {
			$words[$key] = array($word[0], $word[1] / $total);
		}

		return $words;
	}

	public function getWordsRelative(string $id)
	{
		$words = $this->getWordsList($id);
		$wordsClean = [];
		foreach ($words as $key => $word) {
			$wordsClean[] = array($word['word'], $word['relative']);
		}

		return $wordsClean;
	}

	public function createCloud(
		string $ref,
		string $text = '',
		int $size = null,
		string $duration = null)
	{
		if (!isset($size)) {
			$size = 3;
		}
		if (!isset($duration)) {
			$duration = self::DEFAULT_DURATION;
		} elseif (!in_array($duration, self::OPTIONS_DURATION)) {
			$duration = self::DEFAULT_DURATION;
		}
		$duration = date('Y-m-d H:i:s', strtotime($duration));
		$stmt = $this->db->prepare("
			INSERT INTO clouds(code, text, size, delete_t)
			VALUES      (:code, :text, :size, :duration);
		");
		$stmt->bindValue(':code', $ref);
		$stmt->bindValue(':text', $text);
		$stmt->bindValue(':size', $size);
		$stmt->bindValue(':duration', $duration, PDO::PARAM_STR);
		try {
			$stmt->execute();
		} catch (PDOEXception $e) {
			return false;
		}
		return true;
	}

	public function getCloudSize(string $ref)
	{
		$stmt = $this->db->prepare("
			SELECT *
			FROM   clouds
			WHERE  code= :code;
		");
		$stmt->bindValue(':code', $ref, PDO::PARAM_STR);
		$stmt->execute();
		if ($data = $stmt->fetch()) {
			return $data['size'];
		}
		return 0;
	}

	public function getCloudText(string $ref)
	{
		$stmt = $this->db->prepare("
			SELECT *
			FROM   clouds
			WHERE  code = :code;
		");
		$stmt->bindValue(':code', $ref, PDO::PARAM_STR);
		$stmt->execute();
		if ($data = $stmt->fetch()) {
			return $data['text'];
		}
		return null;
	}

	public function countWords(string $cloud)
	{
		$stmt = $this->db->prepare("
			SELECT count(*) as count
			FROM   clouds
			JOIN   words
			ON     id_cloud = cloud_id
			WHERE  code = :code;
		");
		$stmt->bindValue(':code', $cloud, PDO::PARAM_STR);
		$stmt->execute();
		if ($data = $stmt->fetch()) {
			return $data['count'];
		}
		return null;
	}

	public function cleanCloud()
	{
		$stmt = $this->db->prepare("
			DELETE
			FROM  clouds
			WHERE delete_t < CURRENT_TIMESTAMP;
		");
		$stmt->execute();
		return true;
	}

	public function isCloud(string $id)
	{
		$stmt = $this->db->prepare("
			SELECT *
			FROM   clouds
			WHERE  code = :id;
		");
		$stmt->bindValue(':id', $id, PDO::PARAM_STR);
		$stmt->execute();
		if ($stmt->fetch()) {
			return true;
		}
		return false;
	}

}