deepseek_chatbot/api/PromptBuilder.php

<?php

/**
 * PromptBuilder class to build prompts for a chatbot.
 * It allows setting roles, questions, and context, and builds a prompt string or data for API requests.
 */
class PromptBuilder
{
    /**
     * Role of the chatbot, e.g., "You are a helpful assistant."
     * @var string
     */
    private $role = "";

    /**
     * Question asked by the user, e.g., "What is the weather today?"
     * @var string
     */
    private $question = "";

    /**
     * Context for the chatbot, e.g., additional information or data to consider.
     * @var string
     */
    private $context = "";

    /**
     * Allow context to be used in the prompt.
     * If false, the context will not be included in the prompt.
     * @var bool
     */
    private $allowContext = true;

    /**
     * Returns the role of the chatbot.
     * @return string The role of the chatbot.
     */
    public function getRole(){
        return $this->role;
    }

    /**
     * Returns the question of the chatbot.
     * @return string The question of the chatbot.
     */
    public function getQuestion(){
        return $this->question;
    }

    /**
     * Returns the context of the chatbot.
     * @return string The context of the chatbot.
     */
    public function getContext(){
        return $this->context;
    }

    /**
     * Returns whether the context is allowed in the prompt.
     * @return bool True if context is allowed, false otherwise.
     */
    public function getContextAllowness(){
        return $this->allowContext;
    }

    /**
     * Sets the role of the chatbot.
     * @param string $role The role to set for the chatbot.
     */
    public function setRole($role){
        $this->role = $role;
    }

    /**
     * Sets the question for the chatbot.
     * @param string $question The question to set for the chatbot.
     */
    public function setQuestion($question){
        $this->question = $question;
    }

    /**
     * Sets the context for the chatbot.
     * @param string $context The context to set for the chatbot.
     */
    public function setContext($context){
        //TODO: Better context handling in order to bypass token limits
        // Maybe require an Array of context items? (MCP Like?)
        $this->context = $context;

    }

    /**
     * Sets whether the context is allowed in the prompt.
     * @param bool $allowContext True to allow context, false to disallow.
     */
    public function setContextAllowness($allowContext){
        $this->allowContext = $allowContext;
    }

    /**
     * Builds the prompt string for the chatbot.
     * This includes the role, context (if allowed), and question.
     * @return string The complete prompt string.
     */
    public function buildPromptString(){
        $prompt = "Deine Rolle ist: " . $this->role;

        if ($this->allowContext) {
            $prompt .= "\nDu hast folgenden Kontext, auf den du dich NUR fokussierst: " . $this->context;
        }

        $prompt .= "\nDies ist die Frage des Nutzers: " . $this->question;
        $prompt .= "\nBeantworte die Frage so gut es geht\n";
        return $prompt;
    }

    /**
     * Builds the prompt data for API requests.
     * This includes the model, messages (role, question, context), and other parameters.
     * @return string JSON encoded prompt data.
     */
    public function buildPromptData(){
        $messages = [
            ["role" => "system", "content" => $this->getRole()],
            ["role" => "user", "content" => $this->getQuestion()],
        ];
        // add context if allowed
        if ($this->allowContext) {
            $messages[] = ["role" => "context", "content" => $this->getContext()];
        }
        return json_encode([
            "model" => "deepseek-llm-7b-chat",
            "messages" => $messages,
            "temperature" => 0.5,
            "max_tokens" => -1,
            "stream" => false
        ]);
    }
}