<?php

declare( strict_types=1 );

namespace Rowbot\Idna\Bin;

use function array_map;
use function explode;
use function fclose;
use function fgets;
use function file_put_contents;
use function var_export;

use const DIRECTORY_SEPARATOR as DS;

class ViramaDataBuilder extends Builder {
	public static function buildHashMap( string $output ): void {
		$handle = self::getUnicodeDataResource( 'extracted/DerivedCombiningClass.txt' );
		$virama = [];

		while ( ( $line = fgets( $handle ) ) !== false ) {
			if ( $line === "\n" || $line[0] === '#' ) {
				continue;
			}

			[ $data ] = explode( '#', $line );
			$data = array_map( 'trim', explode( ';', $data ) );
			[ $codePoints, $combiningClass ] = $data;

			if ( $combiningClass !== '9' ) {
				continue;
			}

			$codePoints = self::parseCodePoints( $codePoints );
			$diff       = $codePoints[1] - $codePoints[0] + 1;

			for ( $i = 0; $i < $diff; ++ $i ) {
				$virama[ $codePoints[0] + $i ] = (int) $combiningClass;
			}
		}

		fclose( $handle );
		file_put_contents( $output . DS . 'virama.php', "<?php\n\nreturn " . var_export( $virama, true ) . ";\n" );
	}
}