<?php
/**
 * Stored settings.
 *
 * Everything the plugin configures lives in one option row, except the API key,
 * which is kept in its own non-autoloaded row so that it is not loaded into
 * memory on every request and is easy to delete on its own.
 *
 * @package ACS_Article_Generator
 */

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

/**
 * Reads, writes and sanitises the plugin settings.
 */
class ACSAGEN_Settings {

	const OPTION     = 'acsagen_settings';
	const OPTION_KEY = 'acsagen_api_key';

	/**
	 * Default settings.
	 *
	 * @return array
	 */
	public static function defaults() {
		return array(
			'model'             => 'gemini-2.5-flash',
			'site_concept'      => '',
			'output_language'   => 'auto',
			'sample_posts'      => 10,
			'sync_seo_meta'     => 1,
			'draft_category'    => 1,
			'create_categories' => 0,
			'fix_link_anchors'  => 1,
		);
	}

	/**
	 * Create the settings row if it does not exist yet.
	 */
	public static function install_defaults() {
		if ( false === get_option( self::OPTION, false ) ) {
			add_option( self::OPTION, self::defaults() );
		}
	}

	/**
	 * All settings, with defaults filled in.
	 *
	 * @return array
	 */
	public static function all() {
		$stored = get_option( self::OPTION, array() );
		if ( ! is_array( $stored ) ) {
			$stored = array();
		}
		return array_merge( self::defaults(), $stored );
	}

	/**
	 * One setting.
	 *
	 * @param string $key     Setting name.
	 * @param mixed  $default Value to use when the setting is missing.
	 * @return mixed
	 */
	public static function get( $key, $default = '' ) { // phpcs:ignore Universal.NamingConventions.NoReservedKeywordParameterNames.defaultFound -- Public method; renaming the parameter would break callers that use named arguments.
		$all = self::all();
		return array_key_exists( $key, $all ) ? $all[ $key ] : $default;
	}

	/**
	 * Replace the whole settings row with a sanitised version of the input.
	 *
	 * Unknown keys are dropped, every value is forced into the shape the
	 * plugin expects, and anything unusable falls back to the default.
	 *
	 * @param array $input Raw values.
	 * @return array The values that were stored.
	 */
	public static function save( $input ) {
		$defaults = self::defaults();
		$clean    = $defaults;

		if ( ! is_array( $input ) ) {
			update_option( self::OPTION, $clean );
			return $clean;
		}

		if ( isset( $input['model'] ) ) {
			$model = sanitize_text_field( (string) $input['model'] );
			if ( array_key_exists( $model, self::models() ) ) {
				$clean['model'] = $model;
			}
		}

		if ( isset( $input['site_concept'] ) ) {
			$clean['site_concept'] = mb_substr( sanitize_textarea_field( (string) $input['site_concept'] ), 0, 2000 );
		}

		if ( isset( $input['output_language'] ) ) {
			$language = sanitize_text_field( (string) $input['output_language'] );
			if ( array_key_exists( $language, self::languages() ) ) {
				$clean['output_language'] = $language;
			}
		}

		if ( isset( $input['sample_posts'] ) ) {
			$samples = absint( $input['sample_posts'] );
			if ( $samples >= 3 && $samples <= 30 ) {
				$clean['sample_posts'] = $samples;
			}
		}

		$clean['sync_seo_meta']  = ( isset( $input['sync_seo_meta'] ) && '1' === (string) $input['sync_seo_meta'] ) ? 1 : 0;
		$clean['draft_category'] = ( isset( $input['draft_category'] ) && '1' === (string) $input['draft_category'] ) ? 1 : 0;

		$clean['create_categories'] = ( isset( $input['create_categories'] ) && '1' === (string) $input['create_categories'] ) ? 1 : 0;
		$clean['fix_link_anchors']  = ( isset( $input['fix_link_anchors'] ) && '1' === (string) $input['fix_link_anchors'] ) ? 1 : 0;

		update_option( self::OPTION, $clean );

		return $clean;
	}

	/**
	 * The Gemini models offered in the settings screen.
	 *
	 * @return array Model id => label.
	 */
	public static function models() {
		return array(
			'gemini-2.5-flash'      => 'Gemini 2.5 Flash',
			'gemini-2.5-flash-lite' => 'Gemini 2.5 Flash-Lite',
			'gemini-2.5-pro'        => 'Gemini 2.5 Pro',
			'gemini-3.5-flash'      => 'Gemini 3.5 Flash',
			'gemini-3.6-flash'      => 'Gemini 3.6 Flash',
		);
	}

	/**
	 * Languages the article can be written in.
	 *
	 * @return array Value => label.
	 */
	public static function languages() {
		return array(
			'auto' => __( 'Same language as this site', 'acs-article-generator' ),
			'ja'   => __( 'Japanese', 'acs-article-generator' ),
			'en'   => __( 'English', 'acs-article-generator' ),
			'es'   => __( 'Spanish', 'acs-article-generator' ),
			'fr'   => __( 'French', 'acs-article-generator' ),
			'de'   => __( 'German', 'acs-article-generator' ),
			'it'   => __( 'Italian', 'acs-article-generator' ),
			'pt'   => __( 'Portuguese', 'acs-article-generator' ),
			'nl'   => __( 'Dutch', 'acs-article-generator' ),
			'ko'   => __( 'Korean', 'acs-article-generator' ),
			'zh'   => __( 'Chinese', 'acs-article-generator' ),
			'ru'   => __( 'Russian', 'acs-article-generator' ),
			'id'   => __( 'Indonesian', 'acs-article-generator' ),
		);
	}

	/**
	 * The plain language name handed to the model, resolved from the setting
	 * or, for "auto", from the site locale.
	 *
	 * @return string
	 */
	public static function language_for_prompt() {
		$names = array(
			'ja' => 'Japanese',
			'en' => 'English',
			'es' => 'Spanish',
			'fr' => 'French',
			'de' => 'German',
			'it' => 'Italian',
			'pt' => 'Portuguese',
			'nl' => 'Dutch',
			'ko' => 'Korean',
			'zh' => 'Chinese',
			'ru' => 'Russian',
			'id' => 'Indonesian',
		);

		$choice = (string) self::get( 'output_language', 'auto' );

		if ( 'auto' !== $choice && isset( $names[ $choice ] ) ) {
			return $names[ $choice ];
		}

		$locale = strtolower( (string) get_locale() );
		$code   = substr( $locale, 0, 2 );

		if ( isset( $names[ $code ] ) ) {
			return $names[ $code ];
		}

		return 'the same language as the existing posts on this site';
	}

	/**
	 * Whether an API key has been saved.
	 *
	 * @return bool
	 */
	public static function has_api_key() {
		return '' !== self::api_key();
	}

	/**
	 * The stored API key.
	 *
	 * This value is never printed to the screen, never written to a log and
	 * never included in an error message. It is read here and handed straight
	 * to the request header.
	 *
	 * @return string
	 */
	public static function api_key() {
		return trim( (string) get_option( self::OPTION_KEY, '' ) );
	}

	/**
	 * Store an API key in its own non-autoloaded row.
	 *
	 * @param string $key Raw key.
	 */
	public static function save_api_key( $key ) {
		$key = trim( sanitize_text_field( (string) $key ) );

		if ( '' === $key ) {
			return;
		}

		if ( false === get_option( self::OPTION_KEY, false ) ) {
			add_option( self::OPTION_KEY, $key, '', 'no' );
			return;
		}

		update_option( self::OPTION_KEY, $key, 'no' );
	}

	/**
	 * Forget the stored API key.
	 */
	public static function delete_api_key() {
		delete_option( self::OPTION_KEY );
	}
}