<?php

/**
 * Embeddings Factory
 *
 * @package Aisentic/Embeddings
 */

namespace Aisentic\Embeddings;

use Aisentic\Api\Models\Settings;
use NeuronAI\RAG\Embeddings\EmbeddingsProviderInterface;
use NeuronAI\RAG\Embeddings\GeminiEmbeddingsProvider;
use NeuronAI\RAG\Embeddings\OpenAIEmbeddingsProvider;

/**
 * Factory for creating embeddings providers using Neuron AI V2
 */
class Embeddings_Factory {

	/**
	 * Settings instance
	 *
	 * @var Settings
	 */
	private $settings;

	/**
	 * Constructor
	 *
	 * @param Settings $settings Settings instance.
	 */
	public function __construct( Settings $settings ) {
		$this->settings = $settings;
	}

	/**
	 * Create embeddings provider based on settings
	 *
	 * @return EmbeddingsProviderInterface
	 * @throws \Exception If provider is not configured or unsupported.
	 */
	public function create(): EmbeddingsProviderInterface {
		$provider = $this->settings->get( 'vectorDBProviders.pinecone.embeddingProvider', 'gemini' );
		$model    = $this->settings->get( 'vectorDBProviders.pinecone.embeddingModel', 'text-embedding-004' );
		$dims     = $this->settings->get( 'vectorDBProviders.pinecone.embeddingDimensions' );

		switch ( $provider ) {
			case 'gemini':
				return $this->createGeminiProvider( $model, $dims );

			case 'openai':
				return $this->createOpenAIProvider( $model, $dims );

			default:
				throw new \Exception(
					sprintf(
						/* translators: %s: provider name */
						__( 'Unsupported embeddings provider: %s', 'aisentic' ), // phpcs:ignore WordPress.Security.EscapeOutput.ExceptionNotEscaped
						esc_html( $provider )
					)
				);
		}
	}

	/**
	 * Create Gemini embeddings provider
	 *
	 * @param string $model Model name.
	 * @param mixed  $dimensions Embedding dimensions.
	 * @return GeminiEmbeddingsProvider
	 * @throws \Exception If API key is not configured.
	 */
	private function createGeminiProvider( string $model, $dimensions = null ): GeminiEmbeddingsProvider {
		$api_key = $this->settings->get( 'llmProviders.google.apiKey' );

		if ( empty( $api_key ) ) {
			throw new \Exception( 'Google API key is not configured for Gemini embeddings.' );
		}

		$config = [];
		if ( is_int( $dimensions ) && $dimensions > 0 ) {
			// Gemini embeddings supports outputDimensionality config
			$config['outputDimensionality'] = $dimensions;
		}

		return new GeminiEmbeddingsProvider(
			key: $api_key,
			model: $model,
			config: $config
		);
	}

	/**
	 * Create OpenAI embeddings provider
	 *
	 * @param string $model Model name.
	 * @param mixed  $dimensions Embedding dimensions.
	 * @return OpenAIEmbeddingsProvider
	 * @throws \Exception If API key is not configured.
	 */
	private function createOpenAIProvider( string $model, $dimensions = null ): OpenAIEmbeddingsProvider {
		$api_key = $this->settings->get( 'llmProviders.openai.apiKey' );

		if ( empty( $api_key ) ) {
			throw new \Exception( 'OpenAI API key is not configured for OpenAI embeddings.' );
		}

		// The provider accepts dimensions and defaults to 1024 if omitted
		$dims = ( is_int( $dimensions ) && $dimensions > 0 ) ? $dimensions : 1024;

		return new OpenAIEmbeddingsProvider(
			key: $api_key,
			model: $model,
			dimensions: $dims
		);
	}
}