<?php
/**
 * ChatGPT Config Manager for Accessibility Audio TTS.
 *
 * @package Accessibility_Audio_TTS\Features\Text_Correction
 */

namespace Accessibility_Audio_TTS\API;

if ( ! defined( 'ABSPATH' ) ) {
	exit;
}

/**
 * ChatGPT Config Manager.
 *
 * Single Responsibility: API key validation and configuration management.
 */
class ChatGPT_Config_Manager {

	/**
	 * The API key.
	 *
	 * @var string
	 */
	private $api_key;

	/**
	 * Constructor.
	 *
	 * @param string|null $api_key Optional API key override.
	 */
	public function __construct( $api_key = null ) {
		// Debug raw database value before trimming.
		$raw_api_key = $api_key ?? get_option( 'accessibility_audio_tts_chatgpt_api_key', '' );
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] RAW API key from DB length: ' . strlen( $raw_api_key ), true );
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] RAW API key starts with: ' . substr( $raw_api_key, 0, 15 ), true );
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] RAW API key ends with: ' . substr( $raw_api_key, -15 ), true );

		$this->api_key = trim( $raw_api_key );
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] TRIMMED API key length: ' . strlen( $this->api_key ), true );
	}

	/**
	 * Check if the API is available (has valid API key).
	 *
	 * @return bool True if API is available.
	 */
	public function is_available() {
		return ! empty( $this->api_key ) && $this->validate_api_key( $this->api_key );
	}

	/**
	 * Get current API key.
	 *
	 * @return string Current API key.
	 */
	public function get_api_key() {
		return $this->api_key;
	}

	/**
	 * Update API key.
	 *
	 * @param string $api_key New API key.
	 * @return bool Success status.
	 */
	public function update_api_key( $api_key ) {
		$this->api_key = trim( $api_key );
		update_option( 'accessibility_audio_tts_chatgpt_api_key', $this->api_key );
		return true;
	}

	/**
	 * Get all configuration settings.
	 *
	 * @return array Configuration settings.
	 */
	public function get_settings() {
		return array(
			'api_key'     => $this->api_key,
			'has_api_key' => ! empty( $this->api_key ),
			'is_valid'    => $this->is_available(),
		);
	}

	/**
	 * Update all settings.
	 *
	 * @param array $settings Settings to update.
	 * @return bool Success status.
	 */
	public function update_settings( $settings ) {
		if ( isset( $settings['api_key'] ) ) {
			$this->update_api_key( $settings['api_key'] );
		}

		return true;
	}

	/**
	 * Validate API key format.
	 *
	 * @param string $api_key API key to validate.
	 * @return bool True if valid format.
	 */
	public function validate_api_key( $api_key ) {
		if ( empty( $api_key ) ) {
			return false;
		}

		// Check format and length based on key type.
		if ( strpos( $api_key, 'sk-proj-' ) === 0 ) {
			// New format keys (sk-proj-) are around 164 characters.
			return strlen( $api_key ) >= 100 && strlen( $api_key ) <= 200;
		} elseif ( strpos( $api_key, 'sk-' ) === 0 ) {
			// Legacy format keys (sk-) are around 56 characters.
			return strlen( $api_key ) >= 40 && strlen( $api_key ) <= 80;
		}

		return false;
	}

	/**
	 * Clean and reset API key (fix for corrupted keys).
	 *
	 * @param string $new_key New API key to set.
	 * @return bool Success status.
	 */
	public function clean_and_reset_api_key( $new_key ) {
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] CLEAN_RESET: Input key length: ' . strlen( $new_key ), true );
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] CLEAN_RESET: Input key starts: ' . substr( $new_key, 0, 15 ), true );

		// Clean the key - trim and validate format.
		$cleaned_key = trim( $new_key );

		// Validate format.
		if ( ! $this->validate_api_key( $cleaned_key ) ) {
			accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] CLEAN_RESET: Invalid key format after cleaning', true );
			return false;
		}

		// Force delete old key first.
		delete_option( 'accessibility_audio_tts_chatgpt_api_key' );
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] CLEAN_RESET: Old key deleted from database', true );

		// Add new key.
		add_option( 'accessibility_audio_tts_chatgpt_api_key', $cleaned_key, '', 'no' );
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] CLEAN_RESET: New key added to database', true );

		// Verify what was actually saved.
		$saved_key = get_option( 'accessibility_audio_tts_chatgpt_api_key', '' );
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] CLEAN_RESET: Saved key length: ' . strlen( $saved_key ), true );
		accessibility_audio_tts_debug_log( '[ChatGPT_Config_Manager] CLEAN_RESET: Keys match: ' . ( $cleaned_key === $saved_key ? 'YES' : 'NO' ), true );

		if ( $cleaned_key === $saved_key ) {
			$this->api_key = $cleaned_key;
			return true;
		}

		return false;
	}

	/**
	 * Clear all configuration.
	 *
	 * @return bool Success status.
	 */
	public function clear_config() {
		$this->api_key = '';
		delete_option( 'accessibility_audio_tts_chatgpt_api_key' );
		return true;
	}

	/**
	 * Get masked API key for display.
	 *
	 * @return string Masked API key.
	 */
	public function get_masked_api_key() {
		if ( empty( $this->api_key ) ) {
			return '';
		}

		$length = strlen( $this->api_key );
		if ( $length <= 10 ) {
			return str_repeat( '*', $length );
		}

		return substr( $this->api_key, 0, 4 ) . str_repeat( '*', $length - 8 ) . substr( $this->api_key, -4 );
	}

	/**
	 * Get configuration status.
	 *
	 * @return array Status information.
	 */
	public function get_status() {
		return array(
			'configured'    => ! empty( $this->api_key ),
			'valid_format'  => $this->validate_api_key( $this->api_key ),
			'api_available' => $this->is_available(),
			'key_type'      => $this->get_key_type(),
			'masked_key'    => $this->get_masked_api_key(),
		);
	}

	/**
	 * Get API key type.
	 *
	 * @return string Key type (new, legacy, invalid, or empty).
	 */
	private function get_key_type() {
		if ( empty( $this->api_key ) ) {
			return 'empty';
		}

		if ( strpos( $this->api_key, 'sk-proj-' ) === 0 ) {
			return 'new';
		} elseif ( strpos( $this->api_key, 'sk-' ) === 0 ) {
			return 'legacy';
		}

		return 'invalid';
	}
}