<?php

    include "Logger.php";

    /**
     * Classe de Conexao com banco de dados.
     * 
     *  - Criar uma conexao de forma mais rápida.
     *  - Gerar logs da conexao.
     *  - Fazer consultas mais rápidas.
     *
     * @author Lucas Awade
     */
    class Conexao {

        /** @conexao */
        private $connection;
        private $credentials = array();

        /** @DB */
        private $host;
        private $port;
        private $database;
        private $user;
        private $password;

        /** @Logs */
        private $logger;

        const FILE_DB = "/var/www/html/include/bd";

        function __construct($host = null, $user = null, $password = null, $port = null, $database = null) {
            $this->logger = new Logger('ConexaoDB_' . ($host ? str_replace(".", "", $host) : 'local'), true, '');
            $this->logger->debug("Criando instancia de Conexao");

            if ($host && $port && $user && $password) {
                $this->host = $host;
                $this->port = $port;
                $this->database = $database;
                $this->user = $user;
                $this->password = $password;
            } else {
                $this->filedb();
                $this->host = $this->credentials['host_db'];
                $this->port = $this->credentials['porta_db'];
                $this->database = $this->credentials['base_db'];
                $this->user = $this->credentials['usuario'];
                $this->password = $this->credentials['senha'];
            }
        }

        /**
         * Pega as informacoes das credenciais no arquivos padrao "bd";
         */
        private function filedb() {
            if (file_exists(self::FILE_DB)) {
                $contents = fopen(self::FILE_DB, 'r');
                while (!feof($contents) && $contents) {
                    $str = fgets($contents);
                    $dados = explode('=', $str);
                    $this->credentials[strtolower($dados[0])] = str_replace('"', '', $dados[1]);
                }
                fclose($contents);
                $this->credentials = array_filter($this->credentials);
                $this->logger->debug("Credenciais banco de dados: " . print_r($this->credentials, true), debug_backtrace());
            } else {
                $this->logger->error("Nao foi possivel encontrar o arquivo 'bd' em " . self::FILE_DB);
            }
        }

        ########################################################################
        ####                           POSTGRESQL                           ####
        ########################################################################

        public function quotedStr($str) {
            return sprintf("'%s'", pg_escape_string(trim($str)));
        }

        /**
         * Cria uma instancia de conexao com o PostgreSQL e mantém um conexao aberta.
         * @return void
         * @throws Exception
         */
        private function postgresql() {
            $this->logger->error("Conexao com " . __FUNCTION__, debug_backtrace());
            if ($this->connection) {
                return null;
            }
            if ($this->host && $this->user && $this->password && $this->port && $this->database) {
                $this->connection = pg_connect("host={$this->host} port={$this->port} dbname={$this->database} user={$this->user} password={$this->password}");
                $this->pg_get_errors();
                $this->logger->success("Conexao realizada!", debug_backtrace());
            } else {
                $this->logger->error("Autenticacao incompleta! Verifique os dados passados de conexao.", debug_backtrace());
                throw new Exception($this->logger->getText());
            }
        }

        /**
         * Verifica erros de consultas e erros para serem gerados manualmente.
         * @param string $error
         * @throws Exception
         */
        private function pg_get_errors($error = null) {
            if (pg_last_error()) {
                $this->logger->error("Error PostgreSQL [ {$this->host} ] ", debug_backtrace());
                $message = $error ? "Message: " . $error . " | Error DB: " . pg_last_error() : "Error DB: " . pg_last_error();
                $this->logger->error($message, debug_backtrace());
                throw new Exception($message);
            }
        }

        /**
         * Realiza a consulta no banco de dados com o tipo de retorno.
         * 
         * - Busca com a conexao aberta, caso tenha uma sessao encerrada tentará
         * recria-la.
         * 
         * @param string $query
         * @param string $type
         * @return array
         */
        function pg_execute($query, $type = "ALL") {
            try {
                $this->postgresql();
                $result = pg_query($query);
                $this->pg_get_errors();

                if ($this->selectQuery($query)) {
                    switch (strtoupper($type)) {
                        case "ALL":
                            return pg_fetch_all($result);
                        case "ASSOC":
                            return pg_fetch_assoc($result);
                        case "ROW":
                            return pg_fetch_row($result);
                        case "ARRAY":
                            return pg_fetch_array($result);
                    }
                }
                return !$result ? false : true;
            } catch (Exception $ex) {
                $this->logger->error($ex->getMessage());
            }
            return false;
        }

        ########################################################################
        ####                              MySQL                             ####
        ########################################################################

        private function selectQuery($query) {
            $type = explode(' ', $query);
            if (trim(strtoupper($type[0])) == 'SELECT') {
                return true;
            }
            return false;
        }

        /**
         * Cria uma instancia de conexao com o PostgreSQL e mantém um conexao aberta.
         * @return void
         * @throws Exception
         */
        private function mysql() {
            $this->logger->error("Conexao com " . __FUNCTION__, debug_backtrace());
            if ($this->connection) {
                return null;
            }

            if ($this->host && $this->user && $this->password && $this->port && $this->database) {
                $this->connection = mysql_connect($this->host, $this->user, $this->password);
                mysql_select_db($this->database, $this->connection);

                $this->mysql_get_errors();
                $this->logger->success("Conexao realizada!", debug_backtrace());
            } else {
                $this->logger->error("Autenticacao incompleta! Verifique os dados passados de conexao.", debug_backtrace());
                throw new Exception($this->logger->getText());
            }
        }

        /**
         * Verifica erros de consultas e erros para serem gerados manualmente.
         * @param string $error
         * @throws Exception
         */
        private function mysql_get_errors($error = null) {
            if (mysql_error()) {
                $this->logger->error("Error MySQL [ {$this->host} ] ", debug_backtrace());
                $message = $error ? "Message: " . $error . " | Error DB: " . mysql_error() : "Error DB: " . mysql_error();
                $this->logger->error($message, debug_backtrace());
                throw new Exception($message);
            }
        }

        /**
         * Realiza a consulta no banco de dados com o tipo de retorno.
         * 
         * - Busca com a conexao aberta, caso tenha uma sessao encerrada tentará
         * recria-la.
         * 
         * @param string $query
         * @param string $type
         * @return array
         */
        function mysql_execute($query, $type = "ARRAY") {
            try {
                $this->mysql();
                $result = mysql_query($query);
                switch (strtoupper($type)) {
                    case "INSERT":
                        $result = mysql_insert_id();
                        break;
                    case "ASSOC":
                        $result = mysql_fetch_assoc($result);
                        break;
                    case "ROW":
                        $result = mysql_fetch_row($result);
                        break;
                    case "ARRAY":
                        $result = mysql_fetch_array($result);
                        break;
                }
                $this->mysql_get_errors();
                return $result;
            } catch (Exception $ex) {
                $this->logger->error($ex->getMessage());
                return null;
            }
        }

        ########################################################################
        ####                     SISTEMA DE LOGS GERADOS                    ####
        ########################################################################

        /**
         * Metodo para ativar e desativar o registros de log.
         * @param bool $active
         */
        function logger($active = false) {
            $this->logger->setLogger($active);
        }

    }