<?php

/**
 * Environment checks and MCP client configuration helpers.
 *
 * AbiliZen intentionally supports only WordPress Application Passwords for
 * authenticating MCP clients - no OAuth, no API keys, no custom tokens.
 * This keeps the trust boundary identical to the regular WordPress REST
 * API: an MCP client authenticates as a real WordPress user and is bound
 * by that user's capabilities.
 *
 * @package AI_Zen
 */

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

class Aizen_Connection
{

	/**
	 * @return array Settings saved for this plugin (server slug, namespace).
	 */
	public function get_settings(): array
	{
		$defaults = array(
			'server_slug' => 'mcp-adapter-default-server',
			'namespace'   => 'mcp',
		);

		$settings = get_option(AIZEN_OPTION_SETTINGS, array());

		return wp_parse_args(is_array($settings) ? $settings : array(), $defaults);
	}

	/**
	 * The full MCP HTTP endpoint for the default mcp-adapter server.
	 *
	 * @return string
	 */
	public function get_endpoint_url(): string
	{
		$settings = $this->get_settings();

		return trailingslashit(rest_url($settings['namespace'] . '/' . $settings['server_slug']));
	}

	/**
	 * @return bool Whether WordPress core Abilities API is present (6.9+).
	 */
	public function has_abilities_api(): bool
	{
		return function_exists('wp_register_ability') && function_exists('wp_get_abilities');
	}

	/**
	 * @return bool Whether the WordPress/mcp-adapter plugin is active.
	 */
	public function has_mcp_adapter(): bool
	{
		return is_plugin_active('mcp-adapter/mcp-adapter.php');
		///return class_exists('WP\MCP\Core\McpAdapter');
	}

	/**
	 * @return bool Whether WordPress Application Passwords are available on
	 *              this site (core feature since WP 5.6, but can be
	 *              disabled by a filter/host, and requires HTTPS by default).
	 */
	public function has_application_passwords(): bool
	{
		return function_exists('wp_is_application_passwords_available') && wp_is_application_passwords_available();
	}

	/**
	 * @return bool Whether the site is being served over HTTPS, required by
	 *              core for Application Passwords outside local environments.
	 */
	public function is_https(): bool
	{
		return is_ssl();
	}

	/**
	 * @return string Direct link to the current user's "Application Passwords"
	 *                section of their profile screen.
	 */
	public function get_application_password_url(): string
	{
		return admin_url('profile.php#application-passwords-section');
	}

	/**
	 * Builds the JSON snippet for the HTTP/proxy MCP client configuration
	 * (Claude Desktop, Cursor, VS Code, Claude Code, etc.) using the
	 * official @automattic/mcp-wordpress-remote proxy, authenticated with an
	 * Application Password.
	 *
	 * @param string $server_key Key to use inside "mcpServers".
	 * @return string Pretty-printed JSON.
	 */
	public function get_client_config_json(string $server_key = 'mywordpress', string $authcode = ''): string
	{
		$config = array(
			'mcpServers' => array(
				$server_key => array(
					'command' => 'npx',
					'args'    => array('-y', 'mcp-remote', '' . $this->get_endpoint_url() . '', '--header', 'Authorization: Basic ' . $authcode),
					// 'env'     => array(
					// 	'WP_API_URL'      => $this->get_endpoint_url(),
					// 	'WP_API_USERNAME' => 'your-wp-username',
					// 	'WP_API_PASSWORD' => 'xxxx xxxx xxxx xxxx xxxx xxxx',
					// ),
				),
			),
		);

		return wp_json_encode($config, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES);
	}

	/**
	 * Builds the WP-CLI/STDIO config snippet, useful when the MCP client
	 * runs on the same machine as WordPress (local development).
	 *
	 * @return string
	 */
	public function get_stdio_config_json(): string
	{
		$settings = $this->get_settings();

		$config = array(
			'mcpServers' => array(
				'wordpress-local' => array(
					'command' => 'wp',
					'args'    => array(
						'--path=/path/to/your/wordpress',
						'mcp-adapter',
						'serve',
						'--server=' . $settings['server_slug'],
						'--user=admin',
					),
				),
			),
		);

		return wp_json_encode($config, JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES);
	}

	/**
	 * @return string WP-CLI command to install the MCP Adapter plugin.
	 */
	public function get_mcp_adapter_install_command(): string
	{
		return 'wp plugin install https://github.com/WordPress/mcp-adapter/releases/latest/download/mcp-adapter.zip --activate';
	}
}