<?php
/**
 * Format registry and public entry point for barcode generation.
 *
 * @package Barcodegen
 */

defined( 'ABSPATH' ) || exit;

/**
 * Front controller for every supported symbology.
 */
class BCGN_Barcode {

	/**
	 * Supported formats with the metadata used by the admin screen.
	 *
	 * @return array<string,array<string,string>>
	 */
	public static function formats() {
		return array(
			'code128' => array(
				'label'  => __( 'Code 128', 'barcodegen' ),
				'hint'   => __( 'Any ASCII text. The best default for internal codes, tickets and documents.', 'barcodegen' ),
				'sample' => 'BCGN-2026-0001',
			),
			'code39'  => array(
				'label'  => __( 'Code 39', 'barcodegen' ),
				'hint'   => __( 'Digits, A-Z and - . $ / + % and space. Still common on older industrial equipment.', 'barcodegen' ),
				'sample' => 'INV-2026-0001',
			),
			'ean13'   => array(
				'label'  => __( 'EAN-13', 'barcodegen' ),
				'hint'   => __( '12 digits, or 13 with the check digit. Retail products worldwide.', 'barcodegen' ),
				'sample' => '590123412345',
			),
			'ean8'    => array(
				'label'  => __( 'EAN-8', 'barcodegen' ),
				'hint'   => __( '7 digits, or 8 with the check digit. Small retail packages.', 'barcodegen' ),
				'sample' => '9638507',
			),
			'upca'    => array(
				'label'  => __( 'UPC-A', 'barcodegen' ),
				'hint'   => __( '11 digits, or 12 with the check digit. Retail products in the US and Canada.', 'barcodegen' ),
				'sample' => '03600029145',
			),
			'itf14'   => array(
				'label'  => __( 'ITF-14', 'barcodegen' ),
				'hint'   => __( '13 digits, or 14 with the check digit. Cartons and shipping labels.', 'barcodegen' ),
				'sample' => '1540014128876',
			),
		);
	}

	/**
	 * Check whether a format is supported.
	 *
	 * @param string $format Format slug.
	 * @return bool
	 */
	public static function supports( $format ) {
		return array_key_exists( $format, self::formats() );
	}

	/**
	 * Encode a value into bar and space widths.
	 *
	 * @param string $format Format slug.
	 * @param string $text   Value to encode.
	 * @param array  $args   Optional settings.
	 * @return array|WP_Error
	 */
	public static function encode( $format, $text, $args = array() ) {
		$format = strtolower( (string) $format );
		$text   = (string) $text;

		switch ( $format ) {
			case 'code128':
				$symbol = BCGN_Code128::encode( $text, 'auto' );
				break;
			case 'code128a':
			case 'code128b':
			case 'code128c':
				$symbol = BCGN_Code128::encode( $text, substr( $format, -1 ) );
				break;
			case 'code39':
				$symbol = BCGN_Code39::encode( $text, ! empty( $args['checksum'] ), isset( $args['wide_ratio'] ) ? $args['wide_ratio'] : 3 );
				break;
			case 'ean13':
			case 'ean8':
			case 'upca':
				$symbol = BCGN_EAN::encode( $text, $format );
				break;
			case 'itf14':
			case 'itf':
				$symbol = BCGN_ITF::encode( $text, $format, isset( $args['wide_ratio'] ) ? $args['wide_ratio'] : 2 );
				break;
			default:
				return new WP_Error( 'bcgn_format', __( 'Unsupported barcode format.', 'barcodegen' ) );
		}

		if ( is_wp_error( $symbol ) ) {
			return $symbol;
		}

		$quiet = self::quiet_zones( $format );

		if ( isset( $args['quiet'] ) && null !== $args['quiet'] ) {
			$quiet = array( (int) $args['quiet'], (int) $args['quiet'] );
		}

		$symbol['format'] = $format;
		$symbol['quiet']  = $quiet;
		$symbol['lead']   = isset( $symbol['lead'] ) ? $symbol['lead'] : '';
		$symbol['tail']   = isset( $symbol['tail'] ) ? $symbol['tail'] : '';
		$symbol['guard']  = isset( $symbol['guard'] ) ? $symbol['guard'] : array();

		return $symbol;
	}

	/**
	 * Encode a value and render it as inline SVG.
	 *
	 * @param string $format Format slug.
	 * @param string $text   Value to encode.
	 * @param array  $args   Optional settings.
	 * @return string|WP_Error
	 */
	public static function svg( $format, $text, $args = array() ) {
		$symbol = self::encode( $format, $text, $args );

		if ( is_wp_error( $symbol ) ) {
			return $symbol;
		}

		return BCGN_SVG::render( $symbol, $args );
	}

	/**
	 * Quiet zone widths, in modules, for a format.
	 *
	 * @param string $format Format slug.
	 * @return array{0:int,1:int}
	 */
	public static function quiet_zones( $format ) {
		switch ( $format ) {
			case 'ean13':
				return array( 11, 7 );
			case 'upca':
				return array( 9, 9 );
			case 'ean8':
				return array( 7, 7 );
			default:
				return array( 10, 10 );
		}
	}
}