grammar

#!/usr/bin/env php
<?php declare(strict_types=1);

/*
 * This file is part of the Zephir Language Specifications.
 *
 * (c) Zephir Team <team@zephir-lang.com>
 *
 * For the full copyright and license information, please view
 * the LICENSE file that was distributed with this source code.
 */

use Zephir\Exceptions\DuplicateDefinitionException;
use Zephir\Exceptions\NoSpecFileFoundException;
use Zephir\Spec\Files;
use function Zephir\Grammar\extract_grammar;
use function Zephir\Grammar\extract_heading;
use function Zephir\Grammar\get_all_defs;
use function Zephir\Grammar\parse_grammar;
use function Zephir\Grammar\render_grammar;

require_once __DIR__ . '/vendor/autoload.php';

error_reporting(-1);

$specDir = __DIR__ . '/spec';

try {
    $files = new Files($specDir);

    fprintf(STDOUT, 'Render grammars (after GRAMMAR blocks)...%s', PHP_EOL);

    // Collect all defined names (for referencing)
    $names = [];
    foreach ($files() as $fileName => $path) {
        $code = file_get_contents($path);
        $definitions = get_all_defs($code);

        foreach ($definitions as $definition) {
            if (isset($names[$definition->getName()])) {
                throw new DuplicateDefinitionException($definition->getName());
            }

            $names[$definition->getName()] = $fileName;
        }
    }

    // Render grammars
    foreach ($files() as $fileName => $path) {
        $code = $origCode = file_get_contents($path);

        $code = preg_replace_callback(
            '/(<!--\s*GRAMMAR(.*?)-->)\s+<pre>.*?<\/pre>/s',
            function ($matches) use ($names, $fileName) {
                $defs = parse_grammar($matches[2]);
                $rendered = render_grammar($defs, $names, $fileName);
                return $matches[1] . "\n\n" . $rendered;
            },
            $code
        );

        if ($code !== $origCode) {
            file_put_contents($path, $code);
        }
    }

    fprintf(STDOUT, 'Generate summary grammar chapter...%s', PHP_EOL);

    // Pretend that all definitions are inside 19-grammar.md now
    $names = array_fill_keys(array_keys($names), '19-grammar.md');

    $grammarFile = $specDir . '/19-grammar.md';

    $output = <<<'END'
# Grammar

## General

The grammar notation is described in [Grammars section](09-lexical-structure.md#grammars).

## Lexical Grammar


END;

    if (file_exists($specDir . '/09-lexical-structure.md') == false) {
        throw new NoSpecFileFoundException('09-lexical-structure.md');
    }

    $lexical = file_get_contents($specDir . '/09-lexical-structure.md');
    $lexical = strstr($lexical, '## Lexical analysis');
    $output .= extract_grammar($lexical, $names);

    $output .= "\n\n## Syntactic Grammar";

    $skipFiles = ['05-types.md', '09-lexical-structure.md', '19-grammar.md'];

    foreach ($files($skipFiles) as $fileName => $path) {
        $code = file_get_contents($path);
        $grammar = extract_grammar($code, $names);

        if ($grammar === null) {
            continue;
        }

        $heading = extract_heading($code, $fileName);

        $output .= "\n\n### $heading\n\n" . $grammar;
    }

    $output .= "\n";

    file_put_contents($grammarFile, $output);

    echo 'Done!', PHP_EOL;
    exit(0);
} catch (Throwable $e) {
    fprintf(STDERR, "Error: %s%s", $e->getMessage(), PHP_EOL);
    exit(1);
}