<?php

/**
 * @class Backend Request
 * @description A class to control all backend operations of the website.
 * @author Luke Channings
 * @licence CC 2011
 * @depends Imagick
 *
 * -- Return Values for the client-side --
 * @return 0 - Invalid action.
 * @return 1 - Operation completed successfully.
 * @return 2 - Incomplete data.
 * @return 3 - Operation failed.
 * @return 4 - No operation.
 * @return 5 - Dependencies were not satisfied.
 */
class backend_request{

    /**
     * @method __construct
     * @description Initialisation method, will connect to the database and perform an action.
     * @return void
     **/
    function __construct($action){

        // Set MySQL database variables.
        $host = "sophia";
        $username = "root";
        $password = "";
        $database = "carpetkings";

        // Create a new MySQL connection.
        try {

            $this->sock = new PDO("mysql:host=$host;dbname=$database",$username,$password);
            $this->sock->setAttribute(PDO::ATTR_DEFAULT_FETCH_MODE, PDO::FETCH_ASSOC);

        } catch (PDOException $e) {

            echo 'Connection failed: ' . $e->getMessage();

        }

        // Check for Image Magick.
        if ( !class_exists("Imagick") ){

            echo 5;
            return;

        }

        // Make sure the method exists before calling it.
        if ( method_exists($this,$action) && count($_POST) !== 0 ){

            // Echo the result of the method.
            echo $this->$action();

        }else{

            // If there is no method echo 0.
            echo 0;

        }

    }

    /**
     * @method __destruct
     * @description Method to be executed when the class is destroyed. (Will close the MySQL socket.)
     * @return void
     **/
    function __destruct(){

        // Close the MySQL socket.
        $this->sock = null;

    }


    /**
     * @method Add
     * @description Function to add carpets to the database.
     * @return int
     */
    protected function add(){

        $nextid = $this->get_next_id();

        foreach($_POST as $group => $item){

            // Ignore the add item. (It's there for telling the script which method to run.)
            if ( $item === "add" ) continue;

            // Check that all of the neccessary fields are filled in.
            if ( $item["name"] && $item["price"] && $item["description"] && $_FILES[$group] ){

                // Sanitise the POST input.
                $name = htmlentities($item["name"]);
                $price = floatval($item["price"]);
                $desc = htmlentities($item["description"]);
                $fname = $nextid . "-" . $_FILES[$group]["name"]["thumbnail"];

                // Make an SQL string.
                $sql = "INSERT INTO carpets (id,name,price,description,image) VALUES ($nextid,'$name',$price,'$desc','$fname')";

                // Insert the current entry into the database.
                $this->sock->exec($sql);

                // cd to the carpets directory. (If it exists.)
                if ( file_exists("../carpets") ) chdir("../carpets");
                else mkdir("../carpets",0777); chdir("../carpets");

                // Check the the thumbs and large directory exist.
                if ( !file_exists("thumbs") || !file_exists("large") ){

                    // Make sure that the thumbs directory exists.
                    if ( !file_exists("thumbs") ) mkdir("thumbs",0777);
                    else mkdir("large",0777);

                }

                // Move the uploaded image to the current directory.
                move_uploaded_file($_FILES[$group]["tmp_name"]["thumbnail"], $fname);

                // Make an instance of Imagick.
                $image = new Imagick($fname);

                // Make a large(r) image for the side panel.
                $image->thumbnailImage(300,0);

                // Write the large image.
                $image->writeImages("large/" . $fname);

                // Make a thumbnail image.
                $image->thumbnailImage(150,0);

                // Write the thumbnail image.
                $image->writeImages("thumbs/" . $fname);

                // delete the uploaded file.
                unlink($fname);

                // Increment the next ID. (This way we don't have to call get_next_id for each loop.)
                $nextid++;

            }
            else{

                // Skip an entry if it is incomplete.
                continue;

            }


        }

        return 1;

    }

    /**
     * @method Delete
     * @description Method to delete a database entry by ID.
     * @return int
     */
    protected function delete(){

        $id = intval($_POST["id"]);

        if ( !empty($id) ){

            // Delete the entry from the database.
            $this->sock->exec("DELETE FROM carpets WHERE id = {$id}");

            // Check if the operation completed.
            if ( $this->sock->errorCode() ) return 1;

            // If it didn't then let the client know.
            else return 3;
        }
        else{

            // Tell the client there was no ID.
            return 2;

        }

    }

    /**
     * @method Truncate
     * @description Method to truncate the database. (Deletes all values and resets ID counter to default.)
     * @return int
     */
    protected function truncate(){

        // Truncate the table.
        $this->sock->exec("TRUNCATE carpets");

        // Check whether the operation completed successfully.
        if ( $this->sock->errorCode() == 0 ){
            return 1;
        }
        else{
            return 0;
        }

    }

    /**
     * @method List Carpets (JSON)
     * @description Method returns a list of all carpets in the database in JSON form.
     * @return string
     */
    protected function list_carpets_json(){

        // Loop through the results.
        foreach( $this->sock->query("SELECT * FROM carpets") as $row){

            // Append the current row to the result.
            $result[] = $row;

        }

        // Return the JSON string.
        return json_encode($result);

    }

    /**
     * @method List Carpets (HTML)
     * @description Method returns a list of all carpets in the database in JSON form.
     * @return string
     */
    protected function list_carpets_html(){

        // Loop through the results.
        foreach( $this->sock->query("SELECT * FROM carpets") as $row){

            // Construct a list item.
            $result .= '<li><a href="#" rel="' . $row["price"] . '" onmouseover="preloader(carpets/large/';
            $result .= $row["image"] . ')"><img src="carpets/thumbs/' . $row["image"] . '" alt="';
            $result .= $row["name"] . '" /></a><p class="caption">' . $row["name"] . '</p></li>' . "\n";

        }

        // Return the list items.
        return $result;
    }

    /**
     * @method get_next_id
     * @description Will return ID for the next table item.
     * @return int
     */
     protected function get_next_id(){

        // Make a query to find the current highest ID.
        $query =  $this->sock->query("SELECT id FROM carpets ORDER BY id DESC LIMIT 1");

        // Fetch the result into a variable.
        $result = $query->fetch();

        // Return the result plus one.
        return $result["id"] + 1;

     }

}

if (  count($_POST) !== 0 ){

    if ( !empty($_POST["action"]) ) $instance = new backend_request($_POST["action"]);
    else echo 0;

}


?>