xref: /plugin/aichat/helper.php (revision 13dbfc23174f3d6b4ae0540553675c666472eae2) 
1<?php
2
3use dokuwiki\plugin\aichat\Model\AbstractModel;
4use dokuwiki\plugin\aichat\Chunk;
5use dokuwiki\plugin\aichat\Embeddings;
6use dokuwiki\plugin\aichat\Model\OpenAI\GPT35Turbo;
7use dokuwiki\plugin\aichat\Storage\AbstractStorage;
8use dokuwiki\plugin\aichat\Storage\PineconeStorage;
9use dokuwiki\plugin\aichat\Storage\SQLiteStorage;
10
11require_once __DIR__ . '/vendor/autoload.php';
12
13/**
14 * DokuWiki Plugin aichat (Helper Component)
15 *
16 * @license GPL 2 http://www.gnu.org/licenses/gpl-2.0.html
17 * @author  Andreas Gohr <gohr@cosmocode.de>
18 */
19class helper_plugin_aichat extends \dokuwiki\Extension\Plugin
20{
21    /** @var AbstractModel */
22    protected $model;
23    /** @var Embeddings */
24    protected $embeddings;
25    /** @var AbstractStorage */
26    protected $storage;
27
28    /**
29     * Check if the current user is allowed to use the plugin (if it has been restricted)
30     *
31     * @return bool
32     */
33    public function userMayAccess()
34    {
35        global $auth;
36        global $USERINFO;
37        global $INPUT;
38
39        if (!$auth) return true;
40        if (!$this->getConf('restrict')) return true;
41        if (!isset($USERINFO)) return false;
42
43        return auth_isMember($this->getConf('restrict'), $INPUT->server->str('REMOTE_USER'), $USERINFO['grps']);
44    }
45
46    /**
47     * Access the OpenAI client
48     *
49     * @return GPT35Turbo
50     */
51    public function getModel()
52    {
53        if ($this->model === null) {
54            $class = '\\dokuwiki\\plugin\\aichat\\Model\\' . $this->getConf('model');
55
56            if (!class_exists($class)) {
57                throw new \RuntimeException('Configured model not found: ' . $class);
58            }
59            // FIXME for now we only have OpenAI models, so we can hardcode the auth setup
60            $this->model = new $class([
61                'key' => $this->getConf('openaikey'),
62                'org' => $this->getConf('openaiorg')
63            ]);
64        }
65
66        return $this->model;
67    }
68
69    /**
70     * Access the Embeddings interface
71     *
72     * @return Embeddings
73     */
74    public function getEmbeddings()
75    {
76        if ($this->embeddings === null) {
77            // FIXME we currently have only one storage backend, so we can hardcode it
78            $this->embeddings = new Embeddings($this->getModel(), $this->getStorage());
79        }
80
81        return $this->embeddings;
82    }
83
84    /**
85     * Access the Storage interface
86     *
87     * @return AbstractStorage
88     */
89    public function getStorage()
90    {
91        if ($this->storage === null) {
92            if($this->getConf('pinecone_apikey')) {
93                $this->storage = new PineconeStorage();
94            } else {
95                $this->storage = new SQLiteStorage();
96            }
97        }
98
99        return $this->storage;
100    }
101
102    /**
103     * Ask a question with a chat history
104     *
105     * @param string $question
106     * @param array[] $history The chat history [[user, ai], [user, ai], ...]
107     * @return array ['question' => $question, 'answer' => $answer, 'sources' => $sources]
108     * @throws Exception
109     */
110    public function askChatQuestion($question, $history = [])
111    {
112        if ($history) {
113            $standaloneQuestion = $this->rephraseChatQuestion($question, $history);
114        } else {
115            $standaloneQuestion = $question;
116        }
117        return $this->askQuestion($standaloneQuestion);
118    }
119
120    /**
121     * Ask a single standalone question
122     *
123     * @param string $question
124     * @return array ['question' => $question, 'answer' => $answer, 'sources' => $sources]
125     * @throws Exception
126     */
127    public function askQuestion($question)
128    {
129        $similar = $this->getEmbeddings()->getSimilarChunks($question);
130        if ($similar) {
131            $context = implode("\n", array_map(function (Chunk $chunk) {
132                return "\n```\n" . $chunk->getText() . "\n```\n";
133            }, $similar));
134            $prompt = $this->getPrompt('question', ['context' => $context]);
135        } else {
136            $prompt = $this->getPrompt('noanswer');
137        }
138
139        $messages = [
140            [
141                'role' => 'system',
142                'content' => $prompt
143            ],
144            [
145                'role' => 'user',
146                'content' => $question
147            ]
148        ];
149
150        $answer = $this->getModel()->getAnswer($messages);
151
152        return [
153            'question' => $question,
154            'answer' => $answer,
155            'sources' => $similar,
156        ];
157    }
158
159    /**
160     * Rephrase a question into a standalone question based on the chat history
161     *
162     * @param string $question The original user question
163     * @param array[] $history The chat history [[user, ai], [user, ai], ...]
164     * @return string The rephrased question
165     * @throws Exception
166     */
167    public function rephraseChatQuestion($question, $history)
168    {
169        // go back in history as far as possible without hitting the token limit
170        $chatHistory = '';
171        $history = array_reverse($history);
172        foreach ($history as $row) {
173            if (
174                count($this->getEmbeddings()->getTokenEncoder()->encode($chatHistory)) >
175                $this->getModel()->getMaxRephrasingTokenLength()
176            ) {
177                break;
178            }
179
180            $chatHistory =
181                "Human: " . $row[0] . "\n" .
182                "Assistant: " . $row[1] . "\n" .
183                $chatHistory;
184        }
185
186        // ask openAI to rephrase the question
187        $prompt = $this->getPrompt('rephrase', ['history' => $chatHistory, 'question' => $question]);
188        $messages = [['role' => 'user', 'content' => $prompt]];
189        return $this->getModel()->getRephrasedQuestion($messages);
190    }
191
192    /**
193     * Load the given prompt template and fill in the variables
194     *
195     * @param string $type
196     * @param string[] $vars
197     * @return string
198     */
199    protected function getPrompt($type, $vars = [])
200    {
201        $template = file_get_contents($this->localFN('prompt_' . $type));
202
203        $replace = array();
204        foreach ($vars as $key => $val) {
205            $replace['{{' . strtoupper($key) . '}}'] = $val;
206        }
207
208        return strtr($template, $replace);
209    }
210}
211
212