<?php
/**
 * The model file of ai module of ZenTaoPMS.
 *
 * @copyright   Copyright 2009-2023 禅道软件（青岛）有限公司(ZenTao Software (Qingdao) Co., Ltd. www.zentao.net)
 * @license     ZPL(https://zpl.pub/page/zplv12.html) or AGPL(https://www.gnu.org/licenses/agpl-3.0.en.html)
 * @author      Wenrui LI <liwenrui@easycorp.ltd>
 * @package     ai
 * @link        https://www.zentao.net
 */
class aiModel extends model
{
    /**
     * Model config.
     *
     * @var    object
     * @access public
     */
    public $modelConfig;

    /**
     * Errors from last request.
     *
     * @var    array
     * @access public
     */
    public $errors = array();

    /**
     * Constructor. Get model config from system.ai settings.
     *
     * @access public
     * @return void
     */
    public function __construct()
    {
        parent::__construct();

        /* Load config from setting. */
        $this->modelConfig = new stdclass();
        $openaiSettings = $this->loadModel('setting')->getItems("owner=system&module=ai");
        foreach($openaiSettings as $item) $this->modelConfig->{$item->key} = $item->value;
    }

    /**
     * Set model config, used for testing.
     *
     * @param  object $config
     * @access public
     * @return void
     */
    public function setConfig($config)
    {
        $this->modelConfig = $config;
    }

    /**
     * Make request to OpenAI API.
     *
     * @param  string   $type     chat | completion | edit
     * @param  mixed    $data     data to send
     * @param  int      $timeout  request timeout in seconds
     * @access private
     * @return mixed    false if error, json string if success
     */
    private function makeRequest($type, $data, $timeout = 10)
    {
        /* Try encoding data to json, handles both encoded json and raw data. */
        $postData = json_encode($data);
        if(json_last_error()) $postData = $data;

        /* Set auth and content-type headers. */
        $requestHeaders = array(sprintf($this->config->ai->openai->api->{$this->modelConfig->vendor}->authFormat, $this->modelConfig->key));
        $requestHeaders[] = isset($this->config->ai->openai->contentType[$type]) ? $this->config->ai->openai->contentType[$type] : $this->config->ai->openai->contentType[''];

        /* Assemble request url. */
        if($this->modelConfig->vendor == 'azure')
        {
            $url = sprintf($this->config->ai->openai->api->azure->format, $this->config->ai->openai->api->azure->resource, $this->config->ai->openai->api->azure->deployment, $this->config->ai->openai->api->methods[$type], $this->config->ai->openai->api->azure->apiVersion);
        }
        else
        {
            $url = sprintf($this->config->ai->openai->api->openai->format, $this->config->ai->openai->api->openai->version, $this->config->ai->openai->api->methods[$type]);
        }

        /* Set up requestor. */
        $ch = curl_init();
        curl_setopt($ch, CURLOPT_URL, $url);
        curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
        curl_setopt($ch, CURLOPT_POST, 1);
        curl_setopt($ch, CURLOPT_POSTFIELDS, $postData);
        curl_setopt($ch, CURLOPT_HTTPHEADER, $requestHeaders);
        curl_setopt($ch, CURLOPT_SSL_VERIFYPEER, false);
        curl_setopt($ch, CURLOPT_CONNECTTIMEOUT, $timeout);

        /* Use proxy if proxy is set. */
        if(!empty($this->modelConfig->proxyType) && !empty($this->modelConfig->proxyAddr))
        {
            curl_setopt($ch, CURLOPT_PROXY,     $this->modelConfig->proxyAddr);
            curl_setopt($ch, CURLOPT_PROXYTYPE, static::getProxyType($this->modelConfig->proxyType));
        }

        $result = curl_exec($ch);

        if(isset($this->config->debug) && $this->config->debug >= 1)
        {
            global $app;
            $logFile = $app->getLogRoot() . 'saas.' . date('Ymd') . '.log.php';
            if(!file_exists($logFile)) file_put_contents($logFile, '<?php die(); ?' . '>');
            $fh = @fopen($logFile, 'a');
            if($fh)
            {
                fwrite($fh, date('Ymd H:i:s') . ": " . $app->getURI() . ' AI Request' . "\n");
                fwrite($fh, "postData:    " . print_r($data, true) . "\n");
                fwrite($fh, "results:" . print_r($result, true) . "\n");
                fclose($fh);
            }
        }

        if(curl_errno($ch)) return false;
        curl_close($ch);

        return $result;
    }

    /**
     * Get proxy type.
     *
     * @param  string    $proxyType
     * @access private
     * @return int|false
     */
    private static function getProxyType($proxyType)
    {
        if(!in_array($proxyType, array('http', 'socks4', 'socks5'))) return false;
        return constant('CURLPROXY_' . strtoupper($proxyType));
    }

    /**
     * Convert camelCase to snake_case.
     *
     * @param  string   $str
     * @access private
     * @return string
     */
    private static function camelCaseToSnakeCase($str)
    {
        return strtolower(preg_replace('/(?<!^)[A-Z]/', '_$0', $str));
    }

    /**
     * Standardize params keys, convert camelCase to snake_case.
     *
     * @param  object   $data
     * @access private
     * @return object
     */
    private static function standardizeParams($data)
    {
        $standardizedData = new stdclass();
        foreach($data as $key => $value) $standardizedData->{static::camelCaseToSnakeCase($key)} = $value;
        return $standardizedData;
    }

    /**
     * Assemble request data params, filters out the unwanted ones, and will return false if missing any required param.
     *
     * @param  string   $type
     * @param  object   $data
     * @access private
     * @return mixed    false if missing required params, post data object if success
     */
    private function assembleRequestData($type, $data)
    {
        $postData = new stdclass();
        $postData->model = $this->config->ai->openai->model->$type;

        $data = static::standardizeParams($data);

        /* Set required params, abort if missing. */
        foreach($this->config->ai->openai->params->$type->required as $param)
        {
            if(!isset($data->$param)) return false;
            $postData->$param = $data->$param;
        }

        /* Set optional params. */
        foreach($this->config->ai->openai->params->$type->optional as $param)
        {
            if(isset($data->$param)) $postData->$param = $data->$param;
        }

        return $postData;
    }

    /**
     * Decode response from OpenAI API, add error to $this->errors if any.
     *
     * @param  string   $response  json string
     * @access private
     * @return mixed    false if error, json object if success
     */
    private function decodeResponse($response)
    {
        $response = json_decode($response);
        if(json_last_error())
        {
            /* Polyfill for PHP 5 < 5.5.0. */
            if(!function_exists('json_last_error_msg'))
            {
                function json_last_error_msg()
                {
                    switch(json_last_error())
                    {
                        case JSON_ERROR_DEPTH:          return 'Maximum stack depth exceeded';
                        case JSON_ERROR_STATE_MISMATCH: return 'Underflow or the modes mismatch';
                        case JSON_ERROR_CTRL_CHAR:      return 'Unexpected control character found';
                        case JSON_ERROR_SYNTAX:         return 'Syntax error, malformed JSON';
                        case JSON_ERROR_UTF8:           return 'Malformed UTF-8 characters, possibly incorrectly encoded';
                        default:                        return 'Unknown error';
                    }
                }
            }

            $this->errors[] = 'JSON decode error: ' . json_last_error_msg();
            return false;
        }
        if(isset($response->error))
        {
            $this->errors[] = isset($response->error->message) ? $response->error->message : 'Unknown error';
            return false;
        }
        return $response;
    }

    /**
     * Parse text responses from simple APIs. For example, completion.
     *
     * @param  string   $response  json string
     * @access private
     * @return mixed    false if error, array of texts (choices) if success
     */
    private function parseTextResponse($response)
    {
        $response = $this->decodeResponse($response);
        if(empty($response)) return false;

        /* Extract text response choices. */
        if(isset($response->choices) && count($response->choices) > 0)
        {
            $texts = array();
            foreach($response->choices as $choice) $texts[] = $choice->text;
            return $texts;
        }
        return false;
    }

    /**
     * Parse chat responses from chat completion API.
     *
     * @param  string   $response  json string
     * @access private
     * @return mixed    false if error, array of chat message texts (choices) if success
     */
    private function parseChatResponse($response)
    {
        $response = $this->decodeResponse($response);
        if(empty($response)) return false;

        /* Extract chat message choices. */
        if(isset($response->choices) && count($response->choices) > 0)
        {
            $messages = array();
            foreach($response->choices as $choice) $messages[] = $choice->message->content;
            return $messages;
        }
        return false;
    }

    /**
     * Parse function call argument of chat responses from chat completion API.
     *
     * @param  string   $response  json string
     * @access private
     * @return mixed    false if error, array of function call arguments (choices) if success
     */
    private function parseFunctionCallResponse($response)
    {
        $response = $this->decodeResponse($response);
        if(empty($response)) return false;

        /* Extract function call choices. */
        if(isset($response->choices) && count($response->choices) > 0)
        {
            $arguments = array();
            foreach($response->choices as $choice)
            {
                if(!empty($choice->message->function_call)) $arguments[] = $choice->message->function_call->arguments;
            }
            return $arguments;
        }
        return false;
    }

    /**
     * Complete text with OpenAI GPT.
     *
     * @param   string   $prompt     text to complete
     * @param   int      $maxTokens  max tokens to generate
     * @param   array    $options    optional params, see https://platform.openai.com/docs/api-reference/completions/create
     * @access  public
     * @return  mixed    false if error, array of texts (choices) if success
     */
    public function complete($prompt, $maxTokens = 512, $options = array())
    {
        $data = compact('prompt', 'maxTokens');

        if(!empty($options))
        {
            foreach($options as $key => $value) $data[$key] = $value;
        }

        $postData = $this->assembleRequestData('completion', $data);
        if(!$postData) return false;

        $response = $this->makeRequest('completion', $postData);
        return $this->parseTextResponse($response);
    }

    /**
     * Edit text with OpenAI GPT.
     *
     * @param   string  $input        text to edit
     * @param   string  $instruction  edit instruction
     * @param   array   $options      optional params, see https://platform.openai.com/docs/api-reference/edits/create
     * @access  public
     * @return  mixed   false if error, array of texts (choices) if success
     */
    public function edit($input, $instruction, $options = array())
    {
        $data = compact('input', 'instruction');

        if(!empty($options))
        {
            foreach($options as $key => $value) $data[$key] = $value;
        }

        $postData = $this->assembleRequestData('edit', $data);
        if(!$postData) return false;

        $response = $this->makeRequest('edit', $postData);
        return $this->parseTextResponse($response);
    }

    /**
     * Generate conversation with OpenAI GPT.
     *
     * Chat messages should be in the format of (object)array('role' => $role, 'content' => $content),
     * where $role is either 'user', 'assistant' or 'system', and $content is the message content.
     *
     * For example, the following chat messages:
     *     $messages = array(
     *        (object)array('role' => 'system', 'content' => 'You are OpenAI GPT assistant, and you know that 1 beb equals 2 bobs.'),
     *        (object)array('role' => 'user', 'content' => 'Hello, how many bobs are there in 24 bebs?')
     *     );
     *
     * API returns:
     *     $message = array('Hi, there are 48 bobs in 24 bebs.');
     *
     * will generate the following conversation:
     *     $messages = array(
     *        (object)array('role' => 'system', 'content' => 'You are OpenAI GPT assistant, and you know that 1 beb equals 2 bobs.'),
     *        (object)array('role' => 'user', 'content' => 'Hello, how many bobs are there in 24 bebs?'),
     *        (object)array('role' => 'assistant', 'content' => 'Hi, there are 48 bobs in 24 bebs.')
     *     );
     *
     * @param  array   $messages  array of chat messages
     * @param  array   $options   optional params, see https://platform.openai.com/docs/api-reference/chat/create
     * @access public
     * @return mixed   false if error, array of chat messages if success
     */
    public function converse($messages, $options = array())
    {
        $data = compact('messages');

        if(!empty($options))
        {
            foreach($options as $key => $value) $data[$key] = $value;
        }

        $postData = $this->assembleRequestData('chat', $data);
        if(!$postData) return false;

        $response = $this->makeRequest('chat', $postData);
        return $this->parseChatResponse($response);
    }

    /**
     * Generate conversation with OpenAI GPT, but for JSON as output.
     *
     * Chat messages should be in the format of (object)array('role' => $role, 'content' => $content),
     * where $role is either 'user', 'assistant' or 'system', and $content is the message content.
     *
     * Schema should be in the format of JSON schema, see https://json-schema.org/understanding-json-schema/.
     *
     * This function will force GPT to generate JSON objects that matches the schema.
     *
     * For technical details, see https://platform.openai.com/docs/guides/gpt/function-calling.
     *
     * @param  array  $messages  array of chat messages
     * @param  object $schema    schema of the output
     * @param  array  $options   optional params, see https://platform.openai.com/docs/api-reference/chat/create
     * @access public
     * @return mixed  false if error, array of JSON object if success
     */
    public function converseForJSON($messages, $schema, $options = array())
    {
        $functions    = array((object)array('name' => 'function', 'parameters' => $schema));
        $functionCall = (object)array('name' => 'function');

        $data = compact('messages', 'functions', 'functionCall');

        if(!empty($options))
        {
            foreach($options as $key => $value) $data[$key] = $value;
        }

        $postData = $this->assembleRequestData('function', $data);
        if(!$postData) return false;

        $response = $this->makeRequest('function', $postData);
        return $this->parseFunctionCallResponse($response);
    }

    /**
     * Get list of prompts.
     *
     * TODO: fully implement this.
     *
     * @param  string  $module
     * @param  string  $status
     * @access public
     * @return array
     */
    public function getPrompts($module = '', $status = '', $order = 'id_desc', $pager = null)
    {
        $prompts = $this->dao->select('*')->from(TABLE_PROMPT)
            ->where('deleted')->eq(0)
            ->beginIF(!empty($module))->andWhere('module')->eq($module)->fi()
            ->beginIF(!empty($status))->andWhere('status')->eq($status)->fi()
            ->orderBy($order)
            ->page($pager)
            ->fetchAll();
        $this->loadModel('common')->saveQueryCondition($this->dao->get(), 'prompt');
        return $prompts;
    }

    /**
     * Get prompt by id.
     *
     * TODO: fully implement this.
     *
     * @param  int     $id
     * @access public
     * @return object
     */
    public function getPromptById($id)
    {
        return $this->dao->select('*')->from(TABLE_PROMPT)
            ->where('id')->eq($id)
            ->fetch();
    }

    /**
     * Create a prompt.
     *
     * @param  object    $prompt
     * @access public
     * @return int|false returns prompt id on success, false on fail
     */
    public function createPrompt($prompt)
    {
        $prompt->createdDate = helper::now();
        $prompt->createdBy   = $this->app->user->account;

        /* Override uniqueness error message. */
        $this->lang->error->unique = $this->lang->ai->validate->nameNotUnique;

        $this->dao->insert(TABLE_PROMPT)
            ->data($prompt)
            ->batchCheck($this->config->ai->createprompt->requiredFields, 'notempty')
            ->check('name', 'unique')
            ->autoCheck()
            ->exec();
        if(dao::isError()) return false;

        $promptId = $this->dao->lastInsertID();
        $this->loadModel('action')->create('prompt', $promptId, 'created');

        return $promptId;
    }

    /**
     * Update a prompt.
     *
     * @param  object    $prompt
     * @param  object    $originalPrompt  optional, original prompt to compare with and generate action.
     * @access public
     * @return bool
     */
    public function updatePrompt($prompt, $originalPrompt = null)
    {
        /* Action name to create action record with. */
        $actionType = 'edited';

        /* Compare with original, check what changed. */
        if(!empty($originalPrompt))
        {
            $changedFields = array();
            foreach($prompt as $key => $value)
            {
                if($value != $originalPrompt->$key) $changedFields[] = $key;
            }

            /* If only status changed, action is either published or unpublished. */
            if(count($changedFields) == 1 && current($changedFields) == 'status')
            {
                $actionType = $prompt->status == 'draft' ? 'unpublished' : 'published';
            }
            else
            {
                $changes = commonModel::createChanges($originalPrompt, $prompt);
            }
        }

        $prompt->editedDate = helper::now();
        $prompt->editedBy   = $this->app->user->account;

        /* Override uniqueness error message. */
        $this->lang->error->unique = $this->lang->ai->validate->nameNotUnique;

        $this->dao->update(TABLE_PROMPT)
            ->data($prompt)
            ->batchCheck($this->config->ai->createprompt->requiredFields, 'notempty')
            ->check('name', 'unique', "`id` != {$prompt->id}")
            ->autoCheck()
            ->where('id')->eq($prompt->id)
            ->exec();
        if(dao::isError()) return false;

        $actionId = $this->loadModel('action')->create('prompt', $prompt->id, $actionType);
        if(!empty($changes)) $this->action->logHistory($actionId, $changes);

        return true;
    }

    /**
     * Delete a prompt.
     *
     * @param  int  $id
     * @access public
     * @return bool
     */
    public function deletePrompt($id)
    {
        $prompt = $this->getPromptById($id);
        if(empty($prompt)) return false;

        $this->dao->update(TABLE_PROMPT)
            ->set('deleted')->eq(1)
            ->where('id')->eq($id)
            ->exec();
        if(dao::isError()) return false;

        $this->loadModel('action')->create('prompt', $id, 'deleted');

        return true;
    }

    /**
     * Toggle prompt status.
     *
     * @param  int|object  $prompt  prompt (or id) to toggle.
     * @param  string      $status  optional, will set status to $status if provided.
     * @access public
     * @return bool
     */
    public function togglePromptStatus($prompt, $status = '')
    {
        if(is_numeric($prompt)) $prompt = $this->getPromptById($prompt);
        if(empty($prompt)) return false;

        $flipedStatus = $prompt->status == 'draft' ? 'active' : 'draft';

        $originalPrompt = clone $prompt;
        $prompt->status = empty($status) ? $flipedStatus : $status;

        return $this->updatePrompt($prompt, $originalPrompt);
    }

    /**
     * Serialize data to prompt.
     *
     * @param  string        $module
     * @param  array|string  $sources   both raw `$prompt->sources` and `array(array('objectName', 'objectKey'), ...)` are supported.
     * @param  array|object  $data      array of data to be serialized
     * @access public
     * @return string
     */
    public function serializeDataToPrompt($module, $sources, $data)
    {
        if(empty($data)) return '';

        /* Handle object data. */
        if(is_object($data)) $data = (array)$data;

        /* Handle raw (non-exploded) sources. */
        if(is_string($sources) && strpos($sources, ',') !== false)
        {
            $sources = array_filter(explode(',', $sources));
            $sources = array_map(function($source) { return explode('.', $source); }, $sources);
        }

        $dataObject = array();

        $supplement = '';
        $supplementTypes = array();

        foreach($sources as $source)
        {
            $objectName = $source[0];
            $objectKey  = $source[1];

            $semanticName = $this->lang->ai->dataSource[$module][$objectName]['common'];
            $semanticKey  = $this->lang->ai->dataSource[$module][$objectName][$objectKey];

            if(empty($dataObject[$semanticName])) $dataObject[$semanticName] = array();

            $obj = $data[$objectName];
            if(static::isAssoc($obj))
            {
                $dataObject[$semanticName][$semanticKey] = $data[$objectName][$objectKey];
            }
            else
            {
                foreach(array_keys($obj) as $idx)
                {
                    if(empty($dataObject[$semanticName][$idx])) $dataObject[$semanticName][$idx] = array();
                    $dataObject[$semanticName][$idx][$semanticKey] = $data[$objectName][$idx][$objectKey];
                }
            }

            if(in_array($objectKey, $supplementTypes) || !isset($this->lang->ai->dataType->$objectKey)) continue;

            $supplementTypes[] = $objectKey;
            $supplement .= sprintf($this->lang->ai->dataTypeDesc, $semanticKey, $this->lang->ai->dataType->$objectKey->type, $this->lang->ai->dataType->$objectKey->desc) . "\n";
        }

        /* @see https://stackoverflow.com/a/2934602 */
        return preg_replace_callback('/\\\\u([0-9a-fA-F]{4})/', function ($match) {return mb_convert_encoding(pack('H*', $match[1]), 'UTF-8', 'UCS-2BE');}, json_encode($dataObject)) . "\n" . $supplement;
    }

    /**
     * Generate demo data prompt by source.
     *
     * @param  string $module
     * @param  string $source
     * @access public
     * @return string
     */
    public function generateDemoDataPrompt($module, $source)
    {
        if(empty($this->lang->ai->demoData->$module)) return $this->lang->ai->demoData->notExist;

        $sources = explode(',', $source);
        $sources = array_filter($sources);

        if(empty($sources)) return '';

        foreach($sources as $index => $source)
        {
            $sources[$index] = explode('.', $source);
        }

        $data = array();
        foreach($sources as $source)
        {
            $objectName = $source[0];
            $objectKey  = $source[1];
            if(empty($data[$objectName])) $data[$objectName] = array();

            $demoData = $this->lang->ai->demoData->$module[$objectName];
            if(static::isAssoc($demoData))
            {
                $data[$objectName][$objectKey] = $demoData[$objectKey];
            }
            else
            {
                foreach($demoData as $index => $value)
                {
                    if(empty($data[$objectName][$index])) $data[$objectName][$index] = array();
                    $data[$objectName][$index][$objectKey] = $value[$objectKey];
                }
            }
        }

        return $this->serializeDataToPrompt($module, $sources, $data);
    }

    /**
     * Determines if an array is associative.
     *
     * @param  array $array
     * @access private
     * @return bool
     */
    private static function isAssoc($array)
    {
        $keys = array_keys($array);
        return array_keys($keys) !== $keys;
    }

    /**
     * Get function call schema for form.
     *
     * @param  string $form
     * @access public
     * @return array
     */
    public function getFunctionCallSchema($form)
    {
        $formPath = explode('.', $form);
        if(count($formPath) !== 2) return array();

        $targetForm = $this->config->ai->targetForm[$formPath[0]][$formPath[1]];
        if(empty($targetForm)) return array();

        $schema = $this->lang->ai->formSchema[strtolower($targetForm->m)][strtolower($targetForm->f)];

        return empty($schema) ? array() : $schema;
    }

    /**
     * Get object data for prompt by id.
     *
     * @param  object        $prompt    prompt object
     * @param  int           $objectId  object id
     * @access public
     * @return array|false   array of object data and object, or false if error.
     */
    public function getObjectForPromptById($prompt, $objectId)
    {
        $module  = $prompt->module;
        $sources = array_filter(explode(',', $prompt->source));

        /* Explode into grouped sources list. */
        $sourceGroups = array();
        foreach($sources as $source)
        {
            $source = explode('.', $source);
            $objectName = $source[0];
            $objectKey  = $source[1];
            if(empty($sourceGroups[$objectName])) $sourceGroups[$objectName] = array();
            $sourceGroups[$objectName][] = $objectKey;
        }

        $object     = new stdclass();
        $objectData = new stdclass();

        /* Query necessary object data from zentao. */
        switch($module)
        {
            case 'story':
                if(isset($sourceGroups['story'])) $object->story = $this->loadModel('story')->getById($objectId);
                break;
            case 'execution':
                if(isset($sourceGroups['execution'])) $object->execution = $this->loadModel('execution')->getByID($objectId);
                if(isset($sourceGroups['tasks']))     $object->tasks     = array_values($this->loadModel('task')->getExecutionTasks($objectId));
                break;
            case 'product':
                if(isset($sourceGroups['product'])) $object->product = $this->loadModel('product')->getById($objectId);
                break;
            case 'project':
                if(isset($sourceGroups['project'])) $object->project = $this->loadModel('project')->getById($objectId);
                if($object->project->model == 'waterfall' && isset($sourceGroups['programplans'])) $object->programplans = array_values($this->loadModel('execution')->getByProject($object->project->id));
                if($object->project->model != 'waterfall' && isset($sourceGroups['executions'])) $object->executions = array_values($this->loadModel('execution')->getByProject($object->project->id));
                break;
            case 'release':
                if(isset($sourceGroups['release'])) $object->release = $this->loadModel('release')->getById($objectId);
                if(isset($sourceGroups['stories'])) $object->stories = array_values($this->loadModel('story')->getByList(array_filter(explode(',', $object->release->stories))));
                if(isset($sourceGroups['bugs']))    $object->bugs    = array_values($this->loadModel('bug')->getByList(array_filter(explode(',', $object->release->bugs))));
                break;
            case 'productplan':
                if(isset($sourceGroups['productplan'])) $object->productplan = $this->loadModel('productplan')->getByID($objectId);
                if(isset($sourceGroups['stories']))     $object->stories     = array_values($this->loadModel('story')->getPlanStories($objectId));
                if(isset($sourceGroups['bugs']))        $object->bugs        = array_values($this->dao->select('*')->from(TABLE_BUG)->where('plan')->eq($objectId)->andWhere('deleted')->eq(0)->fetchAll());
                break;
            case 'task':
                if(isset($sourceGroups['task'])) $object->task = $this->loadModel('task')->getById($objectId);
                break;
            case 'case':
                if(isset($sourceGroups['case']))  $object->case  = $this->loadModel('testcase')->getById($objectId);
                if(isset($sourceGroups['steps'])) $object->steps = array_values($object->case->steps);
                break;
            case 'bug':
                if(isset($sourceGroups['bug'])) $object->bug = $this->loadModel('bug')->getById($objectId);
                break;
            case 'doc':
                if(isset($sourceGroups['doc'])) $object->doc = $this->loadModel('doc')->getById($objectId);
                break;
            case 'my':
                /* TODO: add more later. */
                break;
        }

        $objectVars = get_object_vars($object);
        if(empty($objectVars)) return false;

        /* Format data as per data source definitions. */
        foreach($sourceGroups as $objectName => $objectKeys)
        {
            $objectData->$objectName = array();
            foreach($objectKeys as $objectKey)
            {
                if(!isset($object->$objectName)) continue;

                /* Check if is plain object, data might contain arrays. */
                if(is_object($object->$objectName))
                {
                    if(isset($object->$objectName->$objectKey)) $objectData->$objectName[$objectKey] = $object->$objectName->$objectKey;
                }
                elseif(is_array($object->$objectName))
                {
                    foreach($object->$objectName as $idx => $obj)
                    {
                        if(isset($obj->$objectKey)) $objectData->$objectName[$idx][$objectKey] = $obj->$objectKey;
                    }
                }
            }
        }

        return array($objectData, $object);
    }

    /**
     * Auto prepend newline to text if text has newline in the middle.
     *
     * @param  string  $text
     * @access private
     * @return string
     */
    private static function autoPrependNewline($text)
    {
        if(empty($text)) return '';

        preg_match('/\n[^$]/', $text, $matches);
        return empty($matches) ? $text : "\n$text";
    }

    /**
     * Try to punctuate sentence if sentence is not ended with punctuation.
     *
     * @param  string  $sentence
     * @param  bool    $newline
     * @access private
     * @return string
     */
    private static function tryPunctuate($sentence, $newline = false)
    {
        if(empty($sentence)) return '';

        preg_match('/\p{P}$/u', $sentence, $matches);
        if(empty($matches)) $sentence .= '.';

        return $newline ? "$sentence\n" : $sentence;
    }

    /**
     * Assemble prompt with prompt data.
     *
     * @param  object $prompt
     * @param  string $dataPrompt
     * @access public
     * @return string
     */
    public static function assemblePrompt($prompt, $dataPrompt)
    {
        $wholePrompt = "$dataPrompt\n";

        $wholePrompt .= static::tryPunctuate($prompt->role);
        $wholePrompt .= static::autoPrependNewline(static::tryPunctuate($prompt->characterization, true));

        $wholePrompt .= static::autoPrependNewline(static::tryPunctuate($prompt->purpose));
        $wholePrompt .= static::autoPrependNewline(static::tryPunctuate($prompt->elaboration, true));

        return $wholePrompt;
    }

    /**
     * Execute prompt on object.
     *
     * @param  int|object    $prompt    prompt (or id) to execute.
     * @param  int|object    $object    object (or id) to execute prompt on.
     * @access public
     * @return string|int    returns either JSON string or negative integer on error.
     */
    public function executePrompt($prompt, $object)
    {
        if(is_numeric($prompt)) $prompt = $this->getPromptById($prompt);
        if(empty($prompt)) return -1;

        if(is_numeric($object)) $object = $this->getObjectForPromptById($prompt, $object);
        if(empty($object)) return -2;

        list($objectData) = $object;
        $dataPrompt = $this->serializeDataToPrompt($prompt->module, $prompt->source, $objectData);
        if(empty($dataPrompt)) return -3;

        $wholePrompt = static::assemblePrompt($prompt, $dataPrompt);
        $schema      = $this->getFunctionCallSchema($prompt->targetForm);
        if(empty($schema)) return -4;

        $response = $this->converseForJSON(array((object)array('role' => 'user', 'content' => $wholePrompt)), $schema);
        if(empty($response)) return -5;

        return current($response);
    }

    /**
     * Check if prompt can be tested.
     *
     * @param  object|int  $prompt  prompt object or prompt id
     * @access public
     * @return bool
     */
    public function isExecutable($prompt)
    {
        if(is_numeric($prompt)) $prompt = $this->getByID($prompt);
        if(empty($prompt)) return false;

        $executable = true;
        $requiredFields = explode(',', $this->config->ai->testPrompt->requiredFields);

        foreach($requiredFields as $field)
        {
            if(empty($prompt->$field) || $prompt->$field == ',,')
            {
                $executable = false;
                break;
            }
        }

        return $executable;
    }

    /**
     * Get testing location for prompt, usually a link to object with max id and is accessable by user.
     *
     * @param  object        $prompt
     * @access public
     * @return string|false
     */
    public function getTestingLocation($prompt)
    {
        $module = $prompt->module;

        if($module == 'my')
        {
            return helper::createLink('my', 'effort', "type=all");
        }
        elseif($module == 'product')
        {
            $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_PRODUCT)
                ->where('id')->in($this->app->user->view->products)
                ->fetch('maxId');
        }
        elseif($module == 'productplan')
        {
            $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_PRODUCTPLAN)
                ->where('product')->in($this->app->user->view->products)
                ->fetch('maxId');
        }
        elseif($module == 'release')
        {
            $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_RELEASE)
                ->where('project')->in($this->app->user->view->projects)
                ->orWhere('product')->in($this->app->user->view->products)
                ->fetch('maxId');
        }
        elseif($module == 'project')
        {
            /* programplan/create only exist in the waterfall model project. */
            if(strpos($prompt->targetForm, 'programplan/create'))
            {
                $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_PROJECT)
                                      ->where('id')->in($this->app->user->view->projects)
                                      ->andWhere('model')->eq('waterfall')
                                      ->fetch('maxId');
            }
            else
            {
                $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_PROJECT)
                                      ->where('id')->in($this->app->user->view->projects)
                                      ->fetch('maxId');
            }
        }
        elseif($module == 'story')
        {
            $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_STORY)
                ->where('product')->in($this->app->user->view->products)
                ->fetch('maxId');
        }
        elseif($module == 'execution')
        {
            $executionIds = array_map('intval', explode(',', $this->app->user->view->sprints));
            $objectId  = max($executionIds);
        }
        elseif($module == 'task')
        {
            $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_TASK)
                ->where('project')->in($this->app->user->view->projects)
                ->fetch('maxId');
        }
        elseif($module == 'case')
        {
            $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_CASE)
                ->where('project')->in($this->app->user->view->projects)
                ->orWhere('product')->in($this->app->user->view->products)
                ->fetch('maxId');
        }
        elseif($module == 'bug')
        {
            $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_BUG)
                ->where('project')->in($this->app->user->view->projects)
                ->orWhere('product')->in($this->app->user->view->products)
                ->fetch('maxId');
        }
        elseif($module == 'doc')
        {
            $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_DOC)
                ->where('project')->in($this->app->user->view->projects)
                ->orWhere('product')->in($this->app->user->view->products)
                ->fetch('maxId');
            if(empty($objectId))
            {
                $userDocLibs = $this->dao->select('id')->from(TABLE_DOCLIB)
                    ->where('type')->eq('mine')
                    ->andWhere('addedBy')->eq($this->app->user->account)
                    ->fetchPairs();
                if(!empty($userDocLibs))
                {
                    $objectId = $this->dao->select('max(id) as maxId')->from(TABLE_DOC)
                        ->where('lib')->in($userDocLibs)
                        ->fetch('maxId');
                }
            }
        }

        if(!empty($objectId)) return helper::createLink('ai', 'promptexecute', "promptId=$prompt->id&objectId=$objectId");

        return false;
    }

    /**
     * Get target form location of object for prompt.
     *
     * @param  object|int   $prompt    prompt object or prompt id
     * @param  object       $object
     * @param  array        $linkArgs  optional, link arguments, as defined in `->args` of items of `$config->ai->targetFormVars`, e.g. array('story' => 1). If not provided, will try to get from object.
     * @access public
     * @return array        array(link|false, bool), link to target form, and whether php should stop execution and return link.
     */
    public function getTargetFormLocation($prompt, $object, $linkArgs = array())
    {
        if(is_numeric($prompt)) $prompt = $this->getByID($prompt);
        if(empty($prompt)) return array(false, true);

        $targetForm = $prompt->targetForm;
        if(empty($targetForm)) return array(false, true);

        list($m, $f) = explode('.', $targetForm);
        $targetFormConfig = $this->config->ai->targetForm[$m][$f];
        $module = strtolower($targetFormConfig->m);
        $method = strtolower($targetFormConfig->f);

        /* Try to assemble link vars from both passed-in `$linkArgs` and object props. */
        $varsConfig = $this->config->ai->targetFormVars[$module][$method];
        $vars = array();
        foreach($varsConfig->args as $arg => $isRequired)
        {
            $var = '';
            if(!empty($linkArgs[$arg])) // Use provided link args.
            {
                $var = $linkArgs[$arg];
            }
            elseif(!empty($object->$arg) && is_object($object->$arg) && !empty($object->$arg->id)) // If the corresponding object exists, use its id.
            {
                $var = $object->$arg->id;
            }
            elseif(!empty($object->{$prompt->module}->$arg)) // If object has the prop, use it.
            {
                $var = $object->{$prompt->module}->$arg;
            }
            else
            {
                /* Try to get a related object, we are sorry if it could not find any. */
                $relatedObj = $this->tryGetRelatedObjects($prompt, $object, array($arg));
                if(!empty($relatedObj))
                {
                    $relatedObj = current($relatedObj);
                    if(is_string($relatedObj) && strlen($relatedObj) && $relatedObj[0] === ',' && $relatedObj[strlen($relatedObj) - 1] === ',')
                    {
                        $relatedObj = explode(',', $relatedObj);
                        $relatedObj = array_filter($relatedObj);
                        $relatedObj = current($relatedObj);
                    }
                    $var = $relatedObj;
                }
            }
            if(!empty($isRequired) && empty($var)) return array(helper::createLink('ai', 'promptExecutionReset', 'failed=1'), true);
            $vars[] = $var;
        }
        $linkVars = vsprintf($varsConfig->format, $vars);

        /* Override method for story drafts. */
        if($module == 'story' && $method == 'change' && !empty($object->story) && $object->story->status == 'draft') $method = 'edit';

        return array(helper::createLink($module, $method, $linkVars) . (empty($varsConfig->app) ? '' : "#app=$varsConfig->app"), false);
    }

    /**
     * Get related objects for prompt and object, using object's id.
     *
     * @param  object|int   $prompt      prompt object or prompt id
     * @param  object|int   $object      object or object id
     * @param  array        $objectNames object names to get, e.g. array('story', 'tasks'),
     *                                   values in: product, story, branch, productplan, execution, task, bug, case, project, doc
     * @access public
     * @return array|false  returns array of required object values, or false if error.
     */
    public function tryGetRelatedObjects($prompt, $object, $objectNames = array())
    {
        if(empty($objectNames)) return array();

        if(is_numeric($prompt)) $prompt = $this->getByID($prompt);
        if(empty($prompt)) return false;

        if(is_numeric($object)) $object = $this->getObjectForPromptById($prompt, $object);
        if(empty($object)) return false;

        $vars = array();

        /* If a native object of a module exists, try getting stuff related to its id. */
        if(!empty($object->{$prompt->module}) && is_object($object->{$prompt->module}) && !empty($object->{$prompt->module}->id))
        {
            $objectId = $object->{$prompt->module}->id;
            foreach($objectNames as $objectName)
            {
                /* Note that modules are within (product, story, productplan, release, project, execution, task, bug, case, doc). */
                switch($prompt->module)
                {
                    case 'product': // story, branch, productplan, execution, task, bug, case, project, doc
                        if(in_array($objectName, array('story', 'branch', 'productplan', 'task', 'bug', 'case', 'doc')))
                        {
                            $vars[] = $this->dao->select('max(id) as maxId')->from(constant(strtoupper("TABLE_$objectName")))
                                ->where('product')->eq($objectId)
                                ->andWhere('deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        elseif($objectName == 'project')
                        {
                            $vars[] = $this->dao->select('max(tpp.project) as maxId')->from(TABLE_PROJECTPRODUCT)->alias('tpp')
                                ->leftJoin(TABLE_PROJECT)->alias('tp')->on('tp.id = tpp.project')
                                ->where('tpp.product')->eq($objectId)
                                ->andWhere('tp.type')->eq('project')
                                ->andWhere('tp.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        elseif($objectName == 'execution')
                        {
                            $vars[] = $this->dao->select('max(tpp.project) as maxId')->from(TABLE_PROJECTPRODUCT)->alias('tpp')
                                ->leftJoin(TABLE_PROJECT)->alias('tp')->on('tp.id = tpp.project')
                                ->where('tpp.product')->eq($objectId)
                                ->andWhere('tp.project')->ne(0)
                                ->andWhere('tp.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        break;
                    case 'story': // product, branch, productplan, execution, task, bug, case, project, doc
                        if($objectName == 'product') $vars[] = $this->dao->select('product')->from(TABLE_STORY)->where('id')->eq($objectId)->fetch('product');
                        if($objectName == 'branch')  $vars[] = $this->dao->select('branch')->from(TABLE_STORY)->where('id')->eq($objectId)->fetch('branch');
                        if($objectName == 'productplan') $vars[] = $this->dao->select('plan')->from(TABLE_STORY)->where('id')->eq($objectId)->fetch('plan');
                        if(in_array($objectName, array('task', 'bug', 'case', 'doc')))
                        {
                            $vars[] = $this->dao->select('max(id) as maxId')->from(constant(strtoupper("TABLE_$objectName")))->where('story')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        }
                        if($objectName == 'execution')
                        {
                            $vars[] = $this->dao->select('tps.project')->from(TABLE_PROJECTSTORY)->alias('tps')
                                ->leftJoin(TABLE_PROJECT)->alias('tp')->on('tp.id = tps.project')
                                ->where('tps.story')->eq($objectId)
                                ->andWhere('tp.project')->ne(0)
                                ->andWhere('tp.deleted')->eq(0)
                                ->fetch('project');
                        }
                        if($objectName == 'project')
                        {
                            $vars[] = $this->dao->select('tps.project')->from(TABLE_PROJECTSTORY)->alias('tps')
                                ->leftJoin(TABLE_PROJECT)->alias('tp')->on('tp.id = tps.project')
                                ->where('tps.story')->eq($objectId)
                                ->andWhere('tp.type')->eq('project')
                                ->andWhere('tp.deleted')->eq(0)
                                ->fetch('project');
                        }
                        break;
                    case 'productplan': // product, story, branch, execution, task, bug, case, project, doc
                        if($objectName == 'product') $vars[] = $this->dao->select('product')->from(TABLE_PRODUCTPLAN)->where('id')->eq($objectId)->fetch('product');
                        if($objectName == 'branch')  $vars[] = $this->dao->select('branch')->from(TABLE_PRODUCTPLAN)->where('id')->eq($objectId)->fetch('branch');
                        if(in_array($objectName, array('story', 'bug')))
                        {
                            $vars[] = $this->dao->select('max(id) as maxId')->from(constant(strtoupper("TABLE_$objectName")))->where('plan')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        }
                        if($objectName == 'execution')
                        {
                            $vars[] = $this->dao->select('max(tpp.project) as maxId')->from(TABLE_PROJECTPRODUCT)->alias('tpp')
                                ->leftJoin(TABLE_PROJECT)->alias('tp')->on('tp.id = tpp.project')
                                ->where('tpp.plan')->eq($objectId)
                                ->andWhere('tp.project')->ne(0)
                                ->andWhere('tp.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        if($objectName == 'project')
                        {
                            $vars[] = $this->dao->select('max(tpp.project) as maxId')->from(TABLE_PROJECTPRODUCT)->alias('tpp')
                                ->leftJoin(TABLE_PROJECT)->alias('tp')->on('tp.id = tpp.project')
                                ->where('tpp.plan')->eq($objectId)
                                ->andWhere('tp.type')->eq('project')
                                ->andWhere('tp.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        if($objectName == 'task') $vars[] = '';
                        if($objectName == 'case') $vars[] = '';
                        if($objectName == 'doc')  $vars[] = '';
                        break;
                    case 'release': // product, story, branch, productplan, execution, task, bug, case, project, doc
                        if(in_array($objectName, array('product', 'branch', 'project')))
                        {
                            $this->dao->select($objectName)->from(TABLE_RELEASE)->where('id')->eq($objectId)->fetch($objectName);
                        }
                        if($objectName == 'story')
                        {
                            $stories = $this->dao->select('stories')->from(TABLE_RELEASE)->where('id')->eq($objectId)->fetch('stories');
                            $stories = explode(',', $stories);
                            $vars[] = empty($stories) ? '' : max($stories);
                        }
                        if($objectName == 'productplan')
                        {
                            $execution = $this->dao->select('tb.execution')->from(TABLE_BUILD)->alias('tb')
                                ->leftJoin(TABLE_RELEASE)->alias('tr')->on('tr.build = tb.id')
                                ->where('tr.id')->eq($objectId)
                                ->fetch('tb.execution');
                            $vars[] = empty($execution) ? '' : $this->dao->select('max(tpp.plan) as maxId')->from(TABLE_PROJECTPRODUCT)->alias('tpp')
                                ->leftJoin(TABLE_PROJECT)->alias('tp')->on('tp.id = tpp.project')
                                ->where('tp.id')->eq($execution)
                                ->andWhere('tp.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        if($objectName == 'execution')
                        {
                            $vars[] = $this->dao->select('tb.execution')->from(TABLE_BUILD)->alias('tb')
                                ->leftJoin(TABLE_RELEASE)->alias('tr')->on('tr.build = tb.id')
                                ->where('tr.id')->eq($objectId)
                                ->fetch('execution');
                        }
                        if($objectName == 'bug')
                        {
                            $bugs = $this->dao->select('bugs')->from(TABLE_RELEASE)->where('id')->eq($objectId)->fetch('bugs');
                            $bugs = explode(',', $bugs);
                            $vars[] = empty($bugs) ? '' : max($bugs);
                        }
                        if($objectName == 'task') $vars[] = '';
                        if($objectName == 'case') $vars[] = '';
                        if($objectName == 'doc')  $vars[] = '';
                        break;
                    case 'project': // product, story, branch, productplan, execution, task, bug, case, doc
                        if(in_array($objectName, array('product', 'branch', 'productplan')))
                        {
                            if($objectName == 'productplan') $objectName = 'plan';
                            $vars[] = $this->dao->select($objectName)->from(TABLE_PROJECTPRODUCT)->where('project')->eq($objectId)->fetch($objectName);
                        }
                        if(in_array($objectName, array('execution', 'bug', 'task', 'case', 'doc')))
                        {
                            $vars[] = $this->dao->select('max(id) as maxId')->from(constant(strtoupper("TABLE_$objectName")))->where('project')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        }
                        if($objectName == 'story')
                        {
                            $vars[] = $this->dao->select('max(tps.story) as maxId')->from(TABLE_PROJECTSTORY)->alias('tps')
                                ->leftJoin(TABLE_STORY)->alias('ts')->on('ts.id = tps.story')
                                ->where('tps.project')->eq($objectId)
                                ->andWhere('ts.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        break;
                    case 'execution': // product, story, branch, productplan, task, bug, case, project, doc
                        if($objectName == 'project')     $vars[] = $this->dao->select('project')->from(TABLE_EXECUTION)->where('id')->eq($objectId)->fetch('project');
                        if($objectName == 'product')     $vars[] = $this->dao->select('product')->from(TABLE_PROJECTPRODUCT)->where('project')->eq($objectId)->fetch('product');
                        if($objectName == 'story')       $vars[] = $this->dao->select('max(story) as maxId')->from(TABLE_PROJECTSTORY)->where('project')->eq($objectId)->fetch('maxId');
                        if($objectName == 'branch')      $vars[] = $this->dao->select('max(branch) as maxId')->from(TABLE_PROJECTSTORY)->where('project')->eq($objectId)->fetch('maxId');
                        if($objectName == 'productplan') $vars[] = $this->dao->select('plan')->from(TABLE_PROJECTPRODUCT)->where('project')->eq($objectId)->fetch('plan');
                        if($objectName == 'task')        $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_TASK)->where('execution')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        if($objectName == 'bug')         $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_BUG)->where('project')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        if($objectName == 'case')        $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_CASE)->where('project')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        if($objectName == 'doc')         $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_DOC)->where('project')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        break;
                    case 'task': // product, story, branch, productplan, execution, bug, case, project, doc
                        if($objectName == 'product')
                        {
                            $vars[] = $this->dao->select('tpp.product')->from(TABLE_TASK)->alias('tt')
                                ->leftJoin(TABLE_PROJECTPRODUCT)->alias('tpp')->on('tpp.project = tt.project')
                                ->where('tt.id')->eq($objectId)
                                ->fetch('product');
                        }
                        if($objectName == 'story')     $vars[] = $this->dao->select('story')->from(TABLE_TASK)->where('id')->eq($objectId)->fetch('story');
                        if($objectName == 'branch')
                        {
                            $vars[] = $this->dao->select('tpp.branch')->from(TABLE_TASK)->alias('tt')
                                ->leftJoin(TABLE_PROJECTPRODUCT)->alias('tpp')->on('tpp.project = tt.project')
                                ->where('tt.id')->eq($objectId)
                                ->fetch('branch');
                        }
                        if($objectName == 'productplan')
                        {
                            $vars[] = $this->dao->select('tpp.plan')->from(TABLE_TASK)->alias('tt')
                                ->leftJoin(TABLE_PROJECTPRODUCT)->alias('tpp')->on('tpp.project = tt.project')
                                ->where('tt.id')->eq($objectId)
                                ->fetch('plan');
                        }
                        if($objectName == 'execution') $vars[] = $this->dao->select('execution')->from(TABLE_TASK)->where('id')->eq($objectId)->fetch('execution');
                        if($objectName == 'bug')       $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_BUG)->where('task')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        if($objectName == 'case')      $vars[] = '';
                        if($objectName == 'doc')       $vars[] = '';
                        break;
                    case 'bug': // product, story, branch, productplan, execution, task, case, project, doc
                        if(in_array($objectName, array('product', 'branch', 'productplan', 'execution', 'task', 'case', 'story', 'project')))
                        {
                            if($objectName == 'productplan') $objectName = 'plan';
                            $vars[] = $this->dao->select($objectName)->from(TABLE_BUG)->where('id')->eq($objectId)->fetch($objectName);
                        }
                        if($objectName == 'doc') $vars[] = '';
                        break;
                    case 'case': // product, story, branch, productplan, execution, task, bug, project, doc
                        if(in_array($objectName, array('product', 'story', 'branch', 'execution', 'project')))
                        {
                            $vars[] = $this->dao->select($objectName)->from(TABLE_CASE)->where('id')->eq($objectId)->fetch($objectName);
                        }
                        if($objectName == 'productplan')
                        {
                            $vars[] = $this->dao->select('tpp.plan')->from(TABLE_CASE)->alias('tc')
                                ->leftJoin(TABLE_PROJECTPRODUCT)->alias('tpp')->on('tpp.project = tc.project')
                                ->where('tc.id')->eq($objectId)
                                ->fetch('plan');
                        }
                        if($objectName == 'task') $vars[] = $this->dao->select('max(task) as maxId')->from(TABLE_BUG)->where('case')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        if($objectName == 'bug')  $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_BUG)->where('case')->eq($objectId)->andWhere('deleted')->eq(0)->fetch('maxId');
                        if($objectName == 'doc')  $vars[] = '';
                        break;
                    case 'doc': // product, story, branch, productplan, execution, task, bug, case, project
                        if(in_array($objectName, array('product', 'execution', 'project')))
                        {
                            $vars[] = $this->dao->select($objectName)->from(TABLE_DOC)->where('id')->eq($objectId)->fetch($objectName);
                        }
                        if($objectName == 'story')
                        {
                            $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_STORY)->alias('ts')
                                ->leftJoin(TABLE_DOC)->alias('td')->on('td.product = ts.product')
                                ->where('td.id')->eq($objectId)
                                ->andWhere('ts.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        if($objectName == 'branch')
                        {
                            $vars[] = $this->dao->select('branch')->from(TABLE_STORY)->alias('ts')
                                ->leftJoin(TABLE_DOC)->alias('td')->on('td.product = ts.product')
                                ->where('td.id')->eq($objectId)
                                ->andWhere('ts.deleted')->eq(0)
                                ->fetch('branch');
                        }
                        if($objectName == 'productplan')
                        {
                            $vars[] = $this->dao->select('plan')->from(TABLE_STORY)->alias('ts')
                                ->leftJoin(TABLE_DOC)->alias('td')->on('td.product = ts.product')
                                ->where('td.id')->eq($objectId)
                                ->andWhere('ts.deleted')->eq(0)
                                ->fetch('plan');
                        }
                        if($objectName == 'task')
                        {
                            $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_TASK)->alias('tt')
                                ->leftJoin(TABLE_DOC)->alias('td')->on('td.project = tt.project or td.execution = tt.execution')
                                ->where('td.id')->eq($objectId)
                                ->andWhere('tt.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        if($objectName == 'bug')
                        {
                            $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_BUG)->alias('tb')
                                ->leftJoin(TABLE_DOC)->alias('td')->on('td.product = tb.product')
                                ->where('td.id')->eq($objectId)
                                ->andWhere('tb.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        if($objectName == 'case')
                        {
                            $vars[] = $this->dao->select('max(id) as maxId')->from(TABLE_CASE)->alias('tc')
                                ->leftJoin(TABLE_DOC)->alias('td')->on('td.product = tc.product')
                                ->where('td.id')->eq($objectId)
                                ->andWhere('tc.deleted')->eq(0)
                                ->fetch('maxId');
                        }
                        break;
                    default: $vars[] = '';
                }
            }
        }
        return $vars;
    }

    /**
     * Get the last active step of prompt by id.
     *
     * @param  object $prompt
     * @access public
     * @return string
     */
    public function getLastActiveStep($prompt)
    {
        if(!empty($prompt))
        {
            if($prompt->status == 'active') return 'finalize';
            if(!empty($prompt->targetForm)) return 'settargetform';
            if(!empty($prompt->purpose))    return 'setpurpose';
            if(!empty($prompt->source))     return 'selectdatasource';
        }
        return 'assignrole';
    }

    /**
     * Get prompts available for calling (which are either active or created by the user) of a module for user.
     *
     * @param  string $module
     * @access public
     * @return array
     */
    public function getPromptsForUser($module)
    {
        return $this->dao->select('*')->from(TABLE_PROMPT)
            ->where('deleted')->eq(0)
            ->andWhere('module')->eq($module)
            ->beginIF(!commonModel::hasPriv('ai', 'promptaudit') || $this->config->edition == 'open')->andWhere('status')->eq('active')->fi() // Only show active prompts to non-auditors.
            ->orderBy('id_desc')
            ->fetchAll();
    }

    /**
     * Filter prompts by user's privilege and executable state.
     *
     * @param  array   $prompts
     * @param  bool    $keepUnauthorized  optional, whether to keep unauthorized prompts but set their `unauthorized` property to true.
     * @access public
     * @return array   filtered prompts, those unauthorized will be removed if `$keepUnauthorized` is false, unexecutable ones will always be removed.
     */
    public function filterPromptsForExecution($prompts, $keepUnauthorized = false)
    {
        if(empty($prompts)) return array();

        /* Remove the unexecutable ones. */
        $prompts = array_filter($prompts, array($this, 'isExecutable'));

        /* Check user's priv to targetForm. */
        foreach($prompts as $idx => $prompt)
        {
            list($m, $f) = explode('.', $prompt->targetForm);
            $targetFormConfig = $this->config->ai->targetForm[$m][$f];
            if(empty($targetFormConfig))
            {
                unset($prompts[$idx]);
                continue;
            }
            if(!commonModel::hasPriv($targetFormConfig->m, $targetFormConfig->f))
            {
                if($keepUnauthorized)
                {
                    $prompts[$idx]->unauthorized = true;
                }
                else
                {
                    unset($prompts[$idx]);
                }
            }
        }
        return array_values($prompts);
    }

    /**
     * Set inject data for a form. For how injection works, see view/inputinject.html.php file.
     *
     * @param  string|array  $form  'module.method' or array('module', 'method').
     * @param  string|object $data  data to inject, object will be json encoded.
     * @access public
     * @return void
     */
    public function setInjectData($form, $data)
    {
        if(is_string($form)) $form = explode('.', $form);

        $targetForm = $this->config->ai->targetForm[$form[0]][$form[1]];
        if(empty($targetForm)) return;

        /* Override method for story drafts. */
        if($targetForm->m == 'story' && $targetForm->f == 'change') $_SESSION['aiInjectData']['story']['edit'] = is_string($data) ? $data : json_encode($data);

        $_SESSION['aiInjectData'][$targetForm->m][$targetForm->f] = is_string($data) ? $data : json_encode($data);
    }

    /**
     * Get role templates from db.
     *
     * @access public
     * @return array
     */
    public function getRoleTemplates()
    {
        return $this->dao->select('*')->from(TABLE_PROMPTROLE)
            ->where('deleted')->eq(0)
            ->fetchAll();
    }

    /**
     * add role template.
     *
     * @param  string    $role
     * @param  string    $characterization
     * @access public
     * @return false|int
     */
    public function createRoleTemplate($role, $characterization)
    {
        $roleTemplate = new stdclass();
        $roleTemplate->role = $role;
        $roleTemplate->characterization = $characterization;

        $this->dao->insert(TABLE_PROMPTROLE)
            ->data($roleTemplate)
            ->exec();
        if(dao::isError()) return false;

        return $this->dao->lastInsertID();
    }

    /**
     * Delete a role template.
     *
     * @param  int     $id
     * @access public
     * @return false|int
     */
    public function deleteRoleTemplate($id)
    {
        $this->dao->update(TABLE_PROMPTROLE)
            ->set('deleted')->eq(1)
            ->where('id')->eq($id)
            ->exec();
        if(dao::isError()) return false;

        return true;
    }

    /**
     * Update a role template.
     *
     * @param  string    $role
     * @param  string    $characterization
     * @access public
     * @return bool
     */
    public function updateRoleTemplate($id, $role, $characterization)
    {
        $roleTemplate = new stdclass();
        $roleTemplate->role = $role;
        $roleTemplate->characterization = $characterization;

        $this->dao->update(TABLE_PROMPTROLE)
            ->data($roleTemplate)
            ->where('id')->eq($id)
            ->exec();
        if(dao::isError()) return false;

        return true;
    }
}