<?php

/**
 * Kunena Component
 *
 * @package       Kunena.Framework
 * @subpackage    Tables
 *
 * @copyright     Copyright (C) 2008 - @currentyear@ Kunena Team. All rights reserved.
 * @license       https://www.gnu.org/copyleft/gpl.html GNU/GPL
 * @link          https://www.kunena.org
 **/

namespace Kunena\Forum\Libraries\Tables;

use Exception;
use Joomla\CMS\Event\AbstractEvent;
use Joomla\CMS\Table\Table;
use Kunena\Forum\Libraries\Exception\KunenaException;
use RuntimeException;
use UnexpectedValueException;

\defined('_JEXEC') or die();

/**
 * Class KunenaTable
 *
 * @since   Kunena 6.0
 */
abstract class KunenaTable extends Table
{
    /**
     * @var     boolean
     * @since   Kunena 6.0
     */
    protected $_exists = false;

    /**
     * @param   null  $keys   keys
     * @param   bool  $reset  reset
     *
     * @return  boolean
     *
     * @throws  Exception
     * @since   Kunena 6.0
     */
    public function load($keys = null, $reset = true)
    {
        // Pre-processing by observers
        $event = AbstractEvent::create(
        	'onTableBeforeLoad',
        	[
                'subject' => $this,
                'keys'    => $keys,
                'reset'   => $reset,
            ]
        );
        $this->getDispatcher()->dispatch('onTableBeforeLoad', $event);

        if (empty($keys)) {
            $empty = true;
            $keys  = [];

            // If empty, use the value of the current key
            foreach ($this->_tbl_keys as $key) {
                $empty      = $empty && empty($this->$key);
                $keys[$key] = $this->$key;
            }

            // If empty primary key there's is no need to load anything
            if ($empty) {
                return true;
            }
        } elseif (!\is_array($keys)) {
            // Load by primary key.
            $keyCount = \count($this->_tbl_keys);

            if ($keyCount) {
                if ($keyCount > 1) {
                    throw new \InvalidArgumentException('Table has multiple primary keys specified, only one primary key value provided.');
                }

                $keys = [$this->getKeyName() => $keys];
            } else {
                throw new \RuntimeException('No table keys defined.');
            }
        }

        if ($reset) {
            $this->reset();
        }

        // Initialise the query.
        $query  = $this->_db->createQuery()
            ->select('*')
            ->from($this->_tbl);
        $fields = array_keys($this->getProperties());

        foreach ($keys as $field => $value) {
            // Check that $field is in the table.
            if (!\in_array($field, $fields)) {
                throw new \UnexpectedValueException(sprintf('Missing field in database: %s &#160; %s.', \get_class($this), $field));
            }

            // Add the search tuple to the query.
            $query->where($this->_db->quoteName($field) . ' = ' . $this->_db->quote($value));
        }

        $this->_db->setQuery($query);

        $row = $this->_db->loadAssoc();

        // Check that we have a result.
        if (empty($row)) {
            $result = false;
        } else {
            // Bind the object with the row and return.
            $result = $this->bind($row);
        }

        // Post-processing by observers
        $event = AbstractEvent::create(
        	'onTableAfterLoad',
        	[
                'subject' => $this,
                'result'  => &$result,
                'row'     => $row,
            ]
        );
        $this->getDispatcher()->dispatch('onTableAfterLoad', $event);

        return $result;
    }

    /**
     * @param   bool  $updateNulls  update
     *
     * @return  boolean
     *
     * @throws  Exception
     * @since   Kunena 6.0
     */
    public function store($updateNulls = false): bool
    {
        // Workaround Joomla 3.2 change.
        // TODO: remove check when we're only supporting J!3.5+.
        $k = isset($this->_tbl_keys) ? $this->_tbl_keys : (array) $this->_tbl_key;

        // Implement JObservableInterface: Pre-processing by observers
        // TODO: remove if when we're only supporting J!3.5+.
        if (isset($this->_observers)) {
            $this->_observers->update('onBeforeStore', [$updateNulls, $k]);
        }

        if ($this->exists()) {
            try {
                $result = $this->updateObject($updateNulls);
            } catch (Exception $e) {
                throw new KunenaException($e->getMessage());
            }
        } else {
            try {
                $result = $this->insertObject();
            } catch (Exception $e) {
                throw new KunenaException($e->getMessage());
            }
        }

        if (!$result) {
            return false;
        }

        $this->_exists = true;

        // Implement JObservableInterface: Post-processing by observers
        // TODO: remove if when we're only supporting J!3.5+.
        if (isset($this->_observers)) {
            $this->_observers->update('onAfterStore', [&$result]);
        }

        return true;
    }

    /**
     * @param   null  $exists  exists
     *
     * @return  boolean
     *
     * @since   Kunena 6.0
     */
    public function exists($exists = null): bool
    {
        $return = $this->_exists;

        if ($exists !== null) {
            $this->_exists = $exists;
        }

        return $return;
    }

    /**
     * Updates a row in a table based on an object's properties.
     *
     * @param   boolean  $nulls  True to update null fields or false to ignore them.
     *
     * @return  boolean  True on success.
     *
     * @throws  RuntimeException
     * @throws  Exception
     * @since   Kunena 6.0
     */
    public function updateObject($nulls = false): bool
    {
        $fields = [];
        $where  = [];

        // Workaround Joomla 3.2 change.
        // TODO: remove check when we're only supporting J!3.5+.
        $tbl_keys = isset($this->_tbl_keys) ? $this->_tbl_keys : (array) $this->_tbl_key;

        // Create the base update statement.
        $statement = 'UPDATE ' . $this->_db->quoteName($this->_tbl) . ' SET %s WHERE %s';

        // Iterate over the object variables to build the query fields/value pairs.
        foreach (get_object_vars($this) as $k => $v) {
            // Only process scalars that are not internal fields.
            if (\is_array($v) || \is_object($v) || $k[0] == '_') {
                continue;
            }

            // Set the primary key to the WHERE clause instead of a field to update.
            if (\in_array($k, $tbl_keys)) {
                $where[] = $this->_db->quoteName($k) . '=' . $this->_db->quote($v);
                continue;
            }

            // Prepare and sanitize the fields and values for the database query.
            if ($v === null) {
                // If the value is null and we want to update nulls then set it.
                if ($nulls) {
                    $val = 'NULL';
                }
                // If the value is null and we do not want to update nulls then ignore this field.
                else {
                    continue;
                }
            }
            // The field is not null so we prep it for update.
            else {
                $val = $this->_db->quote($v);
            }

            // Add the field to be updated.
            $fields[] = $this->_db->quoteName($k) . '=' . $val;
        }

        // We don't have any fields to update.
        if (empty($fields)) {
            return true;
        }

        try {
            $this->_db->transactionStart();

            // Set the query and execute the update.
            $this->_db->setQuery(sprintf($statement, implode(",", $fields), implode(' AND ', $where)));

            $this->_db->execute();

            $this->_db->transactionCommit();
        } catch (Exception $e) {
            // Catch any database errors.
            $this->_db->transactionRollback();

            throw new KunenaException($e->getMessage());

            return false;
        }

        return true;
    }

    /**
     * Inserts a row into a table based on an object's properties.
     *
     * @return  boolean  True on success.
     *
     * @throws  RuntimeException
     * @throws  Exception
     * @since   Kunena 6.0
     */
    protected function insertObject(): bool
    {
        $fields = [];
        $values = [];

        // Workaround Joomla 3.2 change.
        // TODO: remove check when we're only supporting J!3.5+.
        $tbl_keys = isset($this->_tbl_keys) ? $this->_tbl_keys : (array) $this->_tbl_key;

        // Iterate over the object variables to build the query fields and values.
        foreach (get_object_vars($this) as $k => $v) {
            // Only process non-null scalars.
            if (\is_array($v) || \is_object($v) || $v === null) {
                continue;
            }

            // Ignore any internal fields.
            if ($k[0] == '_') {
                continue;
            }

            // Prepare and sanitize the fields and values for the database query.
            $fields[] = $this->_db->quoteName($k);
            $values[] = $this->_db->quote($v);
        }

        try {
            $this->_db->transactionStart();

            // Create the base insert statement.
            $query = $this->_db->createQuery()
                ->insert($this->_db->quoteName($this->_tbl))
                ->columns($fields)
                ->values(implode(',', $values));

            // Set the query and execute the insert.
            $this->_db->setQuery($query);

            if (!$this->_db->execute()) {
                return false;
            }

            // Update the primary key if it exists.
            $id = $this->_db->insertid();

            $this->_db->transactionCommit();
        } catch (Exception $e) {
            // Catch any database errors.
            $this->_db->transactionRollback();

            throw new KunenaException($e->getMessage());

            return false;
        }

        if (\count($tbl_keys) == 1 && $id) {
            $key        = reset($tbl_keys);
            $this->$key = $id;
        }

        return true;
    }

    /**
     * @param   null  $pk  pk
     *
     * @return  boolean
     *
     * @throws  Exception
     * @since   Kunena 6.0
     */
    public function delete($pk = null): bool
    {
        // Workaround Joomla 3.2 change.
        // TODO: remove check when we're only supporting J!3.5+.
        $tbl_keys = isset($this->_tbl_keys) ? $this->_tbl_keys : (array) $this->_tbl_key;

        if (\is_null($pk)) {
            $pk = [];

            foreach ($tbl_keys as $key) {
                $pk[$key] = $this->$key;
            }
        } elseif (!\is_array($pk)) {
            $key = reset($tbl_keys);
            $pk  = [$key => $pk];
        }

        foreach ($tbl_keys as $key) {
            $pk[$key] = \is_null($pk[$key]) ? $this->$key : $pk[$key];

            if ($pk[$key] === null) {
                throw new UnexpectedValueException('Null primary key not allowed.');
            }

            $this->$key = $pk[$key];
        }

        // Implement JObservableInterface: Pre-processing by observers
        // TODO: remove if when we're only supporting J!3.5+.
        if (isset($this->_observers)) {
            $this->_observers->update('onBeforeDelete', [$pk]);
        }

        // Check for a database error.
        try {
            $this->_db->transactionStart();

            // Delete the row by primary key.
            $query = $this->_db->createQuery()
                ->delete($this->_db->quoteName($this->_tbl));

            foreach ($pk as $key => $value) {
                $query->where("{$this->_db->quoteName($key)} = {$this->_db->quote($value)}");
            }

            $this->_db->setQuery($query);

            $this->_db->execute();

            $this->_db->transactionCommit();
        } catch (Exception $e) {
            // Catch any database errors.
            $this->_db->transactionRollback();

            throw new KunenaException($e->getMessage());

            return false;
        }

        // Implement JObservableInterface: Post-processing by observers
        // TODO: remove if when we're only supporting J!3.5+.
        if (isset($this->_observers)) {
            $this->_observers->update('onAfterDelete', [$pk]);
        }

        return true;
    }
}