<?php

namespace App\Console\Commands;

use App\Console\Commands\Contracts\AttributeScanHandler;
use App\Console\Commands\Handlers\GenericSeoAttributeHandler;
use App\Console\Commands\Handlers\LayoutAttributeHandler;
use App\Console\Commands\Handlers\LayoutDataAttributeHandler;
use Illuminate\Console\Command;
use Illuminate\Support\Arr;
use Illuminate\Support\Facades\File;
use Illuminate\Support\Str;
use Symfony\Component\Finder\Finder;

class CheckMissingTranslations extends Command
{
    protected $signature = 'lang:check
                            {locale=en : The locale to check against}
                            {--skip=* : Additional paths, files, or globs to exclude}
                            {--ai : Output a structured prompt for AI to generate missing keys}
                            {--unused : Check for defined translation keys that are never used in codebase}
                            {--no-implicit : Disable heuristic detection of key-like strings in Mail/Notification classes}
                            {--fix : Add missing keys to the language files using placeholder values}
                            {--purge : Remove unused keys from the language files (implies --unused)}
                            {--dry-run : Preview what --fix or --purge would change without writing anything}
                            {--force : Do not ask for confirmation before writing files}
                            {--mark= : Prefix for placeholder values created by --fix, for example TODO}
                            {--all-locales : With --purge, purge every locale instead of only the given one}
                            {--include-json : With --purge, also remove unused JSON keys (risky, strings used by vendor packages are not detected)}';

    protected $description = 'Check for translation keys used in the application that are missing or defined keys that are unused';

    private const WILDCARD = "\x1A";

    private const CALL_PATTERN = <<<'REGEX'
~
(?:
    (?<![\w$>])(?:trans\(\)|app\(\s*['"]translator['"]\s*\))\s*->\s*(?:get|choice|has)
  | (?<![\w$>:])(?:__|trans_choice|trans)
  | @(?:lang|choice)
  | (?<![\w$>])Lang::(?:get|choice|has|hasForLocale|getFromJson)
)
\s*\(\s*(?:key\s*:\s*)?
~x
REGEX;

    private const LITERAL_PATTERN = '/(?|\'((?:[^\'\\\\\r\n]|\\\\.)*)\'|"((?:[^"\\\\\r\n]|\\\\.)*)")/';

    private const KEY_SHAPE = '/^[A-Za-z0-9_\-]+(?:\/[A-Za-z0-9_\-]+)*(?:\.[A-Za-z0-9_\-]+)+$/';

    protected array $scanPaths = [
        'app',
        'routes',
        'config',
        'database',
        'resources/views',
    ];

    protected array $defaultExclusions = [
        'vendor',
        'storage',
        'bootstrap/cache',
        'node_modules',
        'resources/views/vendor',
        '.git',
    ];

    protected array $implicitKeySegments = [
        'Notifications',
        'Notification',
        'Mail',
        'Mails',
        'Mailables',
    ];

    protected array $permissionKeySuffixes = [
        'group-name',
        'viewAny',
        'view',
        'create',
        'update',
        'delete',
    ];

    protected array $ignoredKeys = ['key', 'user', 'admissionSchedule'];

    protected array $ignoredUnusedFiles = [
        'validation',
        'auth',
        'pagination',
        'passwords',
    ];

    protected array $literalKeys = [];

    protected int $scannedFiles = 0;

    /** @var array<string, AttributeScanHandler> */
    protected array $attributeHandlers = [];

    public function __construct()
    {
        parent::__construct();

        $this->registerAttributeHandler(new LayoutDataAttributeHandler());
        $this->registerAttributeHandler(new LayoutAttributeHandler());
        $this->registerAttributeHandler(new GenericSeoAttributeHandler('Seo'));
        $this->registerAttributeHandler(new GenericSeoAttributeHandler('Title'));
    }

    public function registerAttributeHandler(AttributeScanHandler $handler): void
    {
        $this->attributeHandlers[$handler->attributeClass()] = $handler;
    }

    public function handle(): int
    {
        $locale = $this->argument('locale');
        $purge = (bool) $this->option('purge');
        $fix = (bool) $this->option('fix');

        if ($purge && $fix) {
            $this->error('--fix and --purge cannot be combined. Run them separately.');

            return Command::FAILURE;
        }

        if (($this->option('all-locales') || $this->option('include-json')) && ! $purge) {
            $this->error('--all-locales and --include-json can only be used together with --purge.');

            return Command::FAILURE;
        }

        $this->info("Checking translation keys against locale: [{$locale}]...");

        $langData = $this->loadLanguageData($locale);
        $scan = $this->scanCodebase($langData);

        $this->line("Scanned {$this->scannedFiles} file(s), found " . count($scan['keys']) . ' static key(s) and ' . count($scan['patterns']) . ' dynamic pattern(s).');
        $this->newLine();

        if ($this->option('unused') || $purge) {
            return $this->checkUnusedKeys($locale, $langData, $scan);
        }

        $missingKeys = [];

        foreach ($scan['keys'] as $key => $occurrences) {
            if (! $this->hasKey($langData, $key)) {
                $missingKeys[$key] = $occurrences;
            }
        }

        if (empty($missingKeys)) {
            $this->info('All translation keys are properly indexed!');

            return Command::SUCCESS;
        }

        $this->error('Found ' . count($missingKeys) . ' missing translation key(s):');
        $this->newLine();

        $tableData = [];
        foreach ($missingKeys as $key => $occurrences) {
            foreach ($occurrences as $occ) {
                $tableData[] = [$key, $occ['file'] . ':' . $occ['line']];
            }
        }

        $this->table(['Missing Key', 'Used In'], $tableData);

        if ($fix) {
            return $this->fixMissingKeys($locale, $langData, $missingKeys);
        }

        if ($this->option('ai')) {
            $this->outputAiPrompt($locale, $missingKeys);
        } else {
            $this->newLine();
            $this->comment('Tip: Run with --ai to generate a copyable prompt for AI to fix these keys:');
            $this->line("  php artisan lang:check {$locale} --ai");
            $this->comment('Or add placeholders to the language files (preview first with --dry-run):');
            $this->line("  php artisan lang:check {$locale} --fix --dry-run");
        }

        return Command::FAILURE;
    }

    private function checkUnusedKeys(string $locale, array $langData, array $scan): int
    {
        $unusedKeys = $this->findUnusedKeys($langData, $scan);

        if (empty($unusedKeys)) {
            $this->info('No unused translation keys found! All defined keys are actively used.');

            return Command::SUCCESS;
        }

        $this->warn('Found ' . count($unusedKeys) . ' unused translation key(s) in language files:');
        $this->newLine();

        $this->table(['Unused Defined Key'], array_map(fn (string $key) => [$key], $unusedKeys));

        if ($this->option('purge')) {
            return $this->purgeUnusedKeys($locale, $langData, $scan, $unusedKeys);
        }

        $this->newLine();
        $this->comment('Tip: remove them from the language files (preview first with --dry-run):');
        $this->line("  php artisan lang:check {$locale} --purge --dry-run");

        return Command::FAILURE;
    }

    private function findUnusedKeys(array $langData, array $scan): array
    {
        $allDefinedKeys = $this->flattenLangData($langData);
        $unusedKeys = [];

        $usedKeys = [];
        $markUsed = function (string $key) use (&$usedKeys): void {
            $usedKeys[$key] = true;
            $usedKeys[str_replace('/', '.', $key)] = true;
        };

        foreach (array_keys($scan['keys']) as $key) {
            $markUsed($key);
        }

        foreach (array_keys($this->literalKeys) as $key) {
            $markUsed($key);
        }

        $patterns = [];
        foreach (array_keys($scan['patterns']) as $pattern) {
            $patterns[] = $pattern;
            $patterns[] = str_replace('/', '.', $pattern);
        }
        $patterns = array_unique($patterns);

        foreach ($allDefinedKeys as $definedKey) {
            if ($this->isIgnoredUnusedKey($definedKey)) {
                continue;
            }

            $normalizedDefinedKey = str_replace('/', '.', $definedKey);

            if (isset($usedKeys[$definedKey]) || isset($usedKeys[$normalizedDefinedKey])) {
                continue;
            }

            $segments = explode('.', $definedKey);
            for ($length = count($segments) - 1; $length >= 2; $length--) {
                if (isset($usedKeys[implode('.', array_slice($segments, 0, $length))])) {
                    continue 2;
                }
            }

            foreach ($patterns as $pattern) {
                if (Str::is($pattern, $definedKey) || Str::is($pattern, $normalizedDefinedKey)) {
                    continue 2;
                }
            }

            $unusedKeys[] = $definedKey;
        }

        return $unusedKeys;
    }

    private function isIgnoredUnusedKey(string $key): bool
    {
        foreach ($this->ignoredUnusedFiles as $ignored) {
            if (
                str_starts_with($key, "{$ignored}.")
                || str_contains($key, "/{$ignored}.")
                || str_contains($key, ".{$ignored}.")
            ) {
                return true;
            }
        }

        return false;
    }

    private function flattenLangData(array $langData): array
    {
        $flattened = [];

        foreach ($langData as $prefix => $data) {
            if ($prefix === '__json') {
                foreach (array_keys($data) as $jsonKey) {
                    $flattened[] = (string) $jsonKey;
                }

                continue;
            }

            array_push($flattened, ...$this->flattenArray($data, (string) $prefix));
        }

        return $flattened;
    }

    private function flattenArray(array $data, string $prefix): array
    {
        $keys = [];

        foreach ($data as $key => $value) {
            $path = "{$prefix}.{$key}";

            if (is_array($value) && $value !== [] && array_keys($value) !== range(0, count($value) - 1)) {
                array_push($keys, ...$this->flattenArray($value, $path));
            } else {
                $keys[] = $path;
            }
        }

        return $keys;
    }

    private function scanCodebase(array $langData): array
    {
        $keys = [];
        $patterns = [];
        $this->literalKeys = [];
        $this->scannedFiles = 0;

        $cliSkips = array_filter((array) ($this->option('skip') ?? []));
        $basePath = rtrim(str_replace('\\', '/', base_path()), '/');
        $selfPath = str_replace('\\', '/', __FILE__);

        foreach ($this->scanPaths as $path) {
            $dir = base_path($path);

            if (! File::isDirectory($dir)) {
                continue;
            }

            $finder = Finder::create()->files()->in($dir)->name('*.php');

            foreach ($finder as $file) {
                $absolutePath = str_replace('\\', '/', $file->getPathname());

                if ($absolutePath === $selfPath) {
                    continue;
                }

                $relativePath = ltrim(substr($absolutePath, strlen($basePath)), '/');

                if ($this->isExcluded($relativePath, $cliSkips)) {
                    continue;
                }

                $this->scannedFiles++;
                $this->scanFile($file->getContents(), $relativePath, $langData, $keys, $patterns);
            }
        }

        return ['keys' => $keys, 'patterns' => $patterns];
    }

    private function isExcluded(string $relativePath, array $cliSkips): bool
    {
        foreach ($this->defaultExclusions as $excluded) {
            $excluded = trim(str_replace('\\', '/', $excluded), '/');

            if ($relativePath === $excluded || str_starts_with($relativePath, $excluded . '/')) {
                return true;
            }
        }

        foreach ($cliSkips as $skip) {
            $skip = trim(str_replace('\\', '/', (string) $skip), '/');

            if ($skip === '') {
                continue;
            }

            if (str_contains($skip, '*')) {
                if (Str::is($skip, $relativePath) || Str::is('*/' . $skip, $relativePath)) {
                    return true;
                }

                continue;
            }

            if (
                $relativePath === $skip
                || str_starts_with($relativePath, $skip . '/')
                || str_contains($relativePath, '/' . $skip . '/')
                || str_ends_with($relativePath, '/' . $skip)
            ) {
                return true;
            }
        }

        return false;
    }

    private function scanFile(string $content, string $file, array $langData, array &$keys, array &$patterns): void
    {
        $content = $this->stripComments($content);

        $this->scanTranslationCalls($content, $file, $keys, $patterns);
        $this->scanAttributes($content, $file, $keys);
        $this->scanLiteralKeys($content, $file, $langData, $keys);

        if (str_contains($content, 'InteractsWithLabels') && str_contains($content, 'enum ')) {
            foreach ($this->extractEnumTranslationKeys($content) as $info) {
                $this->addOccurrence($keys, $info['key'], $file, $info['line']);
            }
        }

        if (str_contains($content, 'function permissions(')) {
            foreach ($this->extractPermissionTranslationKeys($content) as $info) {
                if ($info['dynamic'] ?? false) {
                    $this->addOccurrence($patterns, $info['key'], $file, $info['line']);
                } else {
                    $this->addOccurrence($keys, $info['key'], $file, $info['line']);
                }
            }
        }
    }

    private function scanTranslationCalls(string $content, string $file, array &$keys, array &$patterns): void
    {
        if (! preg_match_all(self::CALL_PATTERN, $content, $matches, PREG_OFFSET_CAPTURE)) {
            return;
        }

        foreach ($matches[0] as [$text, $offset]) {
            $line = $this->lineAt($content, $offset);

            foreach ($this->parseFirstArgument($content, $offset + strlen($text)) as $result) {
                if ($result['dynamic']) {
                    $this->addOccurrence($patterns, $result['value'], $file, $line);

                    continue;
                }

                if (! $this->isInvalidKey($result['value'])) {
                    $this->addOccurrence($keys, $result['value'], $file, $line);
                }
            }
        }
    }

    private function parseFirstArgument(string $content, int $pos): array
    {
        $len = strlen($content);
        $operands = [];
        $buffer = '';
        $depth = 0;

        for ($i = $pos; $i < $len; $i++) {
            $char = $content[$i];

            if ($char === "'" || $char === '"') {
                $start = $i;

                for ($i++; $i < $len && $content[$i] !== $char; $i++) {
                    if ($content[$i] === '\\') {
                        $i++;
                    }
                }

                $buffer .= substr($content, $start, $i - $start + 1);

                continue;
            }

            if ($char === '(' || $char === '[' || $char === '{') {
                $depth++;
            } elseif ($char === ')' || $char === ']' || $char === '}') {
                if ($depth === 0) {
                    break;
                }
                $depth--;
            } elseif ($depth === 0 && $char === ',') {
                break;
            } elseif ($depth === 0 && $char === '.') {
                $prev = $content[$i - 1] ?? '';
                $next = $content[$i + 1] ?? '';

                $isSpread = $prev === '.' || $next === '.';
                $isDecimal = ctype_digit($prev) && ctype_digit($next);

                if (! $isSpread && ! $isDecimal) {
                    $operands[] = trim($buffer);
                    $buffer = '';

                    continue;
                }
            }

            $buffer .= $char;
        }

        $operands[] = trim($buffer);

        if ($operands[0] === '') {
            return [];
        }

        $value = implode('', array_map(fn (string $op) => $this->decodeOperand($op), $operands));
        $value = preg_replace('/' . self::WILDCARD . '+/', self::WILDCARD, $value);

        if ($value === self::WILDCARD) {
            $results = [];

            foreach ($this->extractLiterals(implode(' ', $operands)) as [$literal]) {
                if (preg_match(self::KEY_SHAPE, $literal)) {
                    $results[] = ['value' => $literal, 'dynamic' => false];
                }
            }

            return $results;
        }

        if (str_contains($value, self::WILDCARD)) {
            return [['value' => str_replace(self::WILDCARD, '*', $value), 'dynamic' => true]];
        }

        return [['value' => $value, 'dynamic' => false]];
    }

    private function decodeOperand(string $operand): string
    {
        if (preg_match('/^\'((?:[^\'\\\\]|\\\\.)*)\'$/s', $operand, $m)) {
            return str_replace(["\\'", '\\\\'], ["'", '\\'], $m[1]);
        }

        if (preg_match('/^"((?:[^"\\\\]|\\\\.)*)"$/s', $operand, $m)) {
            $inner = preg_replace(
                '/\{\$(?:[^{}]|\{[^{}]*\})*\}|(?<!\\\\)\$[A-Za-z_]\w*(?:->\w+|\[[^\]]*\])*/',
                self::WILDCARD,
                $m[1]
            );

            return stripcslashes($inner);
        }

        return self::WILDCARD;
    }

    private function scanAttributes(string $content, string $file, array &$keys): void
    {
        if (empty($this->attributeHandlers)) {
            return;
        }

        $classes = implode('|', array_map('preg_quote', array_keys($this->attributeHandlers)));
        $pattern = '/#\[(' . $classes . ')\s*\(((?:[^)]|\n)*?)\)\]/';

        if (! preg_match_all($pattern, $content, $blocks, PREG_OFFSET_CAPTURE)) {
            return;
        }

        foreach ($blocks[0] as $index => [$fullBlock, $blockOffset]) {
            $attributeName = $blocks[1][$index][0];
            $body = $blocks[2][$index][0];

            if (! isset($this->attributeHandlers[$attributeName])) {
                continue;
            }

            $parsedArguments = $this->parseAttributeArguments($body);
            $extractedKeys = $this->attributeHandlers[$attributeName]->extractTranslationKeys($parsedArguments);

            foreach ($extractedKeys as $key) {
                if (! $this->isInvalidKey($key)) {
                    $line = $this->lineAt($content, $blockOffset);
                    $this->addOccurrence($keys, $key, $file, $line);
                }
            }
        }
    }

    private function parseAttributeArguments(string $body): array
    {
        try {
            $evaluable = preg_replace('/([a-zA-Z0-9_]+)\s*:/', "'$1' =>", $body);
            return eval("return [{$evaluable}];") ?? [];
        } catch (\Throwable) {
            return [];
        }
    }

    private function scanLiteralKeys(string $content, string $file, array $langData, array &$keys): void
    {
        $isImplicitFile = ! $this->option('no-implicit') && $this->isImplicitFile($file);

        foreach ($this->extractLiterals($content) as [$literal, $offset]) {
            if (! preg_match(self::KEY_SHAPE, $literal)) {
                continue;
            }

            $this->literalKeys[$literal] = true;

            if (! $isImplicitFile || ! $this->groupExists($langData, $literal)) {
                continue;
            }

            $ctxStart = max(0, $offset - 41);
            $context = substr($content, $ctxStart, max(0, $offset - 1 - $ctxStart));

            if (preg_match('/(?:view|markdown|html|text|route|config|queue|connection|disk)\s*(?:\(|:|=>)\s*$/i', $context)) {
                continue;
            }

            if (! $this->isInvalidKey($literal)) {
                $this->addOccurrence($keys, $literal, $file, $this->lineAt($content, $offset));
            }
        }
    }

    private function isImplicitFile(string $file): bool
    {
        foreach ($this->implicitKeySegments as $segment) {
            if (preg_match('~(?:^|/)' . preg_quote($segment, '~') . '/~', $file)) {
                return true;
            }
        }

        return false;
    }

    private function groupExists(array $langData, string $key): bool
    {
        $group = explode('.', $key, 2)[0];

        return $group !== '' && $group !== '__json' && isset($langData[$group]);
    }

    private function extractLiterals(string $content): array
    {
        if (! preg_match_all(self::LITERAL_PATTERN, $content, $matches, PREG_OFFSET_CAPTURE)) {
            return [];
        }

        return $matches[1];
    }

    private function stripComments(string $content): string
    {
        $blank = static fn (array $m): string => str_repeat("\n", substr_count($m[0], "\n"));

        $content = preg_replace_callback('/\{\{--.*?--\}\}/s', $blank, $content) ?? $content;
        $content = preg_replace_callback('~^[ \t]*/\*.*?\*/~ms', $blank, $content) ?? $content;

        return preg_replace('~^[ \t]*//.*$~m', '', $content) ?? $content;
    }

    private function lineAt(string $content, int $offset): int
    {
        return substr_count($content, "\n", 0, $offset) + 1;
    }

    private function addOccurrence(array &$bucket, string $key, string $file, int $line): void
    {
        $bucket[$key]["{$file}:{$line}"] = ['file' => $file, 'line' => $line];
    }

    private function extractPermissionTranslationKeys(string $content): array
    {
        $keys = [];

        foreach (explode("\n", $content) as $lineNum => $line) {
            if (preg_match('/[\'"]description[\'"]\s*=>\s*[\'"]([^\'"]+)[\'"]/', $line, $matches)) {
                if (! $this->isInvalidKey($matches[1])) {
                    $keys[] = ['key' => $matches[1], 'line' => $lineNum + 1];
                }
            }
        }

        if (preg_match_all('/generatePolicy\(\s*[\'"]([^\'"]+)[\'"]/', $content, $matches, PREG_OFFSET_CAPTURE)) {
            foreach ($matches[1] as [$modelName, $offset]) {
                $line = $this->lineAt($content, $offset);

                foreach ($this->permissionKeySuffixes as $suffix) {
                    $keys[] = ['key' => "permissions.{$modelName}.{$suffix}", 'line' => $line];
                }

                $keys[] = ['key' => "permissions.{$modelName}.*", 'line' => $line, 'dynamic' => true];
            }
        }

        return $keys;
    }

    private function extractEnumTranslationKeys(string $content): array
    {
        if (! preg_match('/namespace\s+([^;]+);/', $content, $namespaceMatch)) {
            return [];
        }

        if (! preg_match('/enum\s+([^\s:]+)/', $content, $enumMatch)) {
            return [];
        }

        $fqcn = trim($namespaceMatch[1]) . '\\' . trim($enumMatch[1]);
        $enumSlug = Str::snake(trim($enumMatch[1]));

        if (Str::startsWith($fqcn, 'App\\Domains\\')) {
            $domain = Str::between($fqcn, 'App\\Domains\\', '\\Enums\\');
            $keyPrefix = 'domains/' . Str::kebab($domain) . "/enum.{$enumSlug}";
        } elseif (Str::startsWith($fqcn, 'App\\UI\\Enums\\')) {
            $keyPrefix = "ui/enum.{$enumSlug}";
        } else {
            $keyPrefix = "enum.{$enumSlug}";
        }

        $keys = [];

        foreach (explode("\n", $content) as $lineNum => $line) {
            if (preg_match('/case\s+[A-Za-z0-9_]+\s*=\s*[\'"]([^\'"]+)[\'"]\s*;/', $line, $caseMatch)) {
                $keys[] = ['key' => "{$keyPrefix}.{$caseMatch[1]}", 'line' => $lineNum + 1];
            }
        }

        return $keys;
    }

    private function loadLanguageData(string $locale): array
    {
        $langData = [];
        $langPath = lang_path($locale);
        $jsonPath = lang_path("{$locale}.json");

        if (File::exists($jsonPath)) {
            $langData['__json'] = json_decode(File::get($jsonPath), true) ?? [];
        }

        if (File::isDirectory($langPath)) {
            foreach (File::allFiles($langPath) as $file) {
                if ($file->getExtension() !== 'php') {
                    continue;
                }

                $relativePath = str_replace('\\', '/', $file->getRelativePathname());
                $content = require $file->getPathname();

                if (is_array($content)) {
                    $langData[substr($relativePath, 0, -4)] = $content;
                }
            }
        }

        return $langData;
    }

    private function hasKey(array $langData, string $key): bool
    {
        if (isset($langData['__json']) && array_key_exists($key, $langData['__json'])) {
            return true;
        }

        if (! str_contains($key, '.')) {
            return false;
        }

        foreach ($langData as $prefix => $data) {
            if ($prefix === '__json') {
                continue;
            }

            if (str_starts_with($key, $prefix . '.')) {
                $item = substr($key, strlen($prefix) + 1);

                if (Arr::has($data, $item)) {
                    return true;
                }
            }

            $normalizedPrefix = str_replace('/', '.', $prefix);
            $normalizedKey = str_replace('/', '.', $key);

            if (str_starts_with($normalizedKey, $normalizedPrefix . '.')) {
                $item = substr($normalizedKey, strlen($normalizedPrefix) + 1);

                if (Arr::has($data, $item)) {
                    return true;
                }
            }
        }

        return false;
    }

    private function isInvalidKey(string $key): bool
    {
        return $key === ''
            || str_contains($key, '::')
            || preg_match('/^\$\w+$/', $key) === 1
            || preg_match('/^\{[A-Za-z0-9_]+\}$/', $key) === 1
            || str_contains($key, '...')
            || str_contains($key, ')]')
            || in_array($key, $this->ignoredKeys, true);
    }

    private function fixMissingKeys(string $locale, array $langData, array $missingKeys): int
    {
        ksort($missingKeys);

        $mark = (string) ($this->option('mark') ?? '');
        $mark = $mark === '' ? '' : rtrim($mark) . ' ';

        $data = $langData;
        $dirty = [];
        $added = [];
        $conflicts = [];

        foreach (array_keys($missingKeys) as $key) {
            [$bucket, $item] = $this->resolveTarget($key);

            if ($bucket === '__json') {
                $value = $mark . $key;
                $data['__json'][$key] = $value;
            } else {
                $value = $mark . $this->humanize($item);
                $data[$bucket] ??= [];

                if (! $this->setPath($data[$bucket], $item, $value)) {
                    $conflicts[] = $key;

                    continue;
                }
            }

            $dirty[$bucket] = true;
            $added[$key] = ['bucket' => $bucket, 'value' => $value];
        }

        $skippedFiles = [];
        foreach (array_keys($dirty) as $bucket) {
            if ($bucket === '__json') {
                continue;
            }

            $path = lang_path("{$locale}/{$bucket}.php");

            if (! $this->isSafelyRewritable($path)) {
                $skippedFiles[$bucket] = $path;
                unset($dirty[$bucket]);
            }
        }

        $rows = [];
        foreach ($added as $key => $info) {
            if (isset($skippedFiles[$info['bucket']])) {
                continue;
            }

            $rows[] = [$key, $info['value'], $this->langFileLabel($locale, $info['bucket'])];
        }

        $this->newLine();

        if (! empty($rows)) {
            $this->info('The following keys will be added:');
            $this->table(['Key', 'Placeholder Value', 'File'], $rows);
        }

        foreach ($conflicts as $key) {
            $this->error("Cannot add [{$key}]: a parent segment already holds a plain string value. Resolve it manually.");
        }

        foreach ($skippedFiles as $bucket => $path) {
            $this->warn('Skipped ' . $this->relativePath($path) . ': it contains executable PHP (closures, constants, function calls) and cannot be rewritten safely. Add its keys manually.');
        }

        if (empty($dirty)) {
            return Command::FAILURE;
        }

        if (! $this->shouldWrite('Write ' . count($rows) . ' key(s) into ' . count($dirty) . ' file(s)? Comments and custom formatting in those files will be lost.')) {
            return Command::FAILURE;
        }

        foreach (array_keys($dirty) as $bucket) {
            $this->writeLangFile($locale, $bucket, $data[$bucket]);
        }

        $this->info('Added ' . count($rows) . ' placeholder key(s) to ' . count($dirty) . ' file(s). Replace the placeholder values with real translations.');

        return (empty($conflicts) && empty($skippedFiles)) ? Command::SUCCESS : Command::FAILURE;
    }

    private function purgeUnusedKeys(string $locale, array $langData, array $scan, array $unusedKeys): int
    {
        $includeJson = (bool) $this->option('include-json');
        $locales = $this->option('all-locales') ? $this->discoverLocales() : [$locale];

        $plans = [];
        $skippedJson = 0;
        $skippedFiles = [];

        foreach ($locales as $loc) {
            $data = $loc === $locale ? $langData : $this->loadLanguageData($loc);
            $unused = $loc === $locale ? $unusedKeys : $this->findUnusedKeys($data, $scan);
            $removed = [];

            foreach ($unused as $key) {
                $bucket = $this->locateKey($data, $key);

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

                if ($bucket === '__json') {
                    if (! $includeJson) {
                        $skippedJson++;

                        continue;
                    }

                    unset($data['__json'][$key]);
                } else {
                    $this->forgetPath($data[$bucket], substr($key, strlen($bucket) + 1));
                }

                $removed[$bucket][] = $key;
            }

            foreach (array_keys($removed) as $bucket) {
                if ($bucket === '__json') {
                    continue;
                }

                $path = lang_path("{$loc}/{$bucket}.php");

                if (! $this->isSafelyRewritable($path)) {
                    $skippedFiles[$path] = true;
                    unset($removed[$bucket]);
                }
            }

            if (! empty($removed)) {
                $plans[$loc] = ['data' => $data, 'removed' => $removed];
            }
        }

        $this->newLine();

        foreach (array_keys($skippedFiles) as $path) {
            $this->warn('Skipped ' . $this->relativePath($path) . ': it contains executable PHP (closures, constants, function calls) and cannot be rewritten safely. Edit it manually.');
        }

        if ($skippedJson > 0) {
            $this->comment("{$skippedJson} unused JSON key(s) were left untouched. Use --include-json to remove them as well.");
        }

        if (empty($plans)) {
            $this->warn('Nothing can be purged automatically.');

            return Command::FAILURE;
        }

        $rows = [];
        $total = 0;
        $fileCount = 0;

        foreach ($plans as $loc => $plan) {
            foreach ($plan['removed'] as $bucket => $keys) {
                $rows[] = [$loc, $this->langFileLabel($loc, $bucket), count($keys)];
                $total += count($keys);
                $fileCount++;
            }
        }

        $this->info('The following keys will be removed:');
        $this->table(['Locale', 'File', 'Keys to Remove'], $rows);

        if (! $this->shouldWrite("Remove {$total} key(s) from {$fileCount} file(s)? Comments and custom formatting in those files will be lost.")) {
            return Command::FAILURE;
        }

        foreach ($plans as $loc => $plan) {
            foreach (array_keys($plan['removed']) as $bucket) {
                $this->writeLangFile($loc, $bucket, $plan['data'][$bucket] ?? []);
            }
        }

        $this->info("Removed {$total} unused key(s) from {$fileCount} file(s).");

        return empty($skippedFiles) ? Command::SUCCESS : Command::FAILURE;
    }

    private function shouldWrite(string $question): bool
    {
        if ($this->option('dry-run')) {
            $this->comment('Dry run: no files were written.');

            return false;
        }

        if ($this->option('force')) {
            return true;
        }

        if (! $this->confirm($question, false)) {
            $this->comment('Aborted. No files were written.');

            return false;
        }

        return true;
    }

    private function resolveTarget(string $key): array
    {
        if (preg_match(self::KEY_SHAPE, $key)) {
            [$group, $item] = explode('.', $key, 2);

            return [$group, $item];
        }

        return ['__json', $key];
    }

    private function locateKey(array $data, string $key): ?string
    {
        if (isset($data['__json']) && array_key_exists($key, $data['__json'])) {
            return '__json';
        }

        $group = explode('.', $key, 2)[0];

        return ($group !== '__json' && isset($data[$group])) ? $group : null;
    }

    private function humanize(string $item): string
    {
        $segments = explode('.', $item);
        $last = (string) end($segments);

        $words = preg_replace('/(?<=[a-z0-9])(?=[A-Z])/', ' ', $last);
        $words = trim(str_replace(['-', '_'], ' ', $words));

        return ucfirst(mb_strtolower($words));
    }

    private function setPath(array &$data, string $path, string $value): bool
    {
        $segments = explode('.', $path);
        $last = count($segments) - 1;
        $ref = &$data;

        foreach ($segments as $index => $segment) {
            if ($index === $last) {
                if (array_key_exists($segment, $ref)) {
                    return false;
                }

                $ref[$segment] = $value;

                return true;
            }

            if (! array_key_exists($segment, $ref)) {
                $ref[$segment] = [];
            }

            if (! is_array($ref[$segment])) {
                return false;
            }

            $ref = &$ref[$segment];
        }

        return false;
    }

    private function forgetPath(array &$data, string $path): void
    {
        if (array_key_exists($path, $data)) {
            unset($data[$path]);

            return;
        }

        $this->forgetSegments($data, explode('.', $path));
    }

    private function forgetSegments(array &$data, array $segments): void
    {
        $first = array_shift($segments);

        if (! array_key_exists($first, $data)) {
            return;
        }

        if ($segments === []) {
            unset($data[$first]);

            return;
        }

        if (! is_array($data[$first])) {
            return;
        }

        $this->forgetSegments($data[$first], $segments);

        if ($data[$first] === []) {
            unset($data[$first]);
        }
    }

    private function writeLangFile(string $locale, string $bucket, array $data): void
    {
        if ($bucket === '__json') {
            $json = json_encode(
                $data === [] ? new \stdClass : $data,
                JSON_PRETTY_PRINT | JSON_UNESCAPED_UNICODE | JSON_UNESCAPED_SLASHES | JSON_FORCE_OBJECT
            );

            File::put(lang_path("{$locale}.json"), $json . "\n");

            return;
        }

        $path = lang_path("{$locale}/{$bucket}.php");
        File::ensureDirectoryExists(dirname($path));
        File::put($path, "<?php\n\nreturn " . $this->exportPhpArray($data) . ";\n");
    }

    private function exportPhpArray(array $data, int $depth = 0): string
    {
        if ($data === []) {
            return '[]';
        }

        $indent = str_repeat('    ', $depth + 1);
        $isList = array_keys($data) === range(0, count($data) - 1);
        $lines = [];

        foreach ($data as $key => $value) {
            $keyPart = $isList ? '' : $this->exportScalar($key) . ' => ';
            $valuePart = is_array($value) ? $this->exportPhpArray($value, $depth + 1) : $this->exportScalar($value);

            $lines[] = $indent . $keyPart . $valuePart . ',';
        }

        return "[\n" . implode("\n", $lines) . "\n" . str_repeat('    ', $depth) . ']';
    }

    private function exportScalar(mixed $value): string
    {
        return match (true) {
            is_string($value) => "'" . str_replace(['\\', "'"], ['\\\\', "\\'"], $value) . "'",
            is_bool($value) =>$value ? 'true' : 'false',
            $value === null => 'null',
            default => var_export($value, true),
        };
    }

    private function isSafelyRewritable(string $path): bool
    {
        if (! File::exists($path)) {
            return true;
        }

        $allowedTokens = [
            T_OPEN_TAG, T_WHITESPACE, T_COMMENT, T_DOC_COMMENT, T_RETURN, T_ARRAY,
            T_DOUBLE_ARROW, T_CONSTANT_ENCAPSED_STRING, T_LNUMBER, T_DNUMBER, T_DECLARE,
        ];

        foreach (token_get_all(File::get($path)) as$token) {
            if (is_string($token)) {
                if (! str_contains('[],();-+=', $token)) {
                    return false;
                }

                continue;
            }

            [$id, $text] =$token;

            if (in_array($id,$allowedTokens, true)) {
                continue;
            }

            if ($id === T_STRING && in_array(strtolower($text), ['true', 'false', 'null', 'strict_types'], true)) {
                continue;
            }

            return false;
        }

        return true;
    }

    private function discoverLocales(): array
    {
        $locales = [];

        foreach (File::directories(lang_path()) as $dir) {
            if (basename($dir) !== 'vendor') {
                $locales[] = basename($dir);
            }
        }

        foreach (File::glob(lang_path('*.json')) ?: [] as $jsonFile) {
            $locales[] = basename($jsonFile, '.json');
        }

        return array_values(array_unique($locales));
    }

    private function langFileLabel(string $locale, string$bucket): string
    {
        return $this->relativePath(
            $bucket === '__json' ? lang_path("{$locale}.json") : lang_path("{$locale}/{$bucket}.php")
        );
    }

    private function relativePath(string $path): string
    {
        $base = rtrim(str_replace('\\', '/', base_path()), '/');

        return ltrim(str_replace($base, '', str_replace('\\', '/',$path)), '/');
    }

    private function outputAiPrompt(string $locale, array$missingKeys): void
    {
        $this->newLine();$this->info('==================== AI TRANSLATION PROMPT ====================');
        $this->comment('Copy the block below and paste it into ChatGPT, Claude, Gemini, or Cursor:');$this->newLine();

        $groupedByDomain = [];
        foreach ($missingKeys as$key => $occurrences) {$parts = explode('.', $key);$domain = count($parts) > 1 ? array_shift($parts) : 'general';
            $groupedByDomain[$domain][$key] = array_column($occurrences, 'file');
        }

        $prompt = "I have missing translation keys in my Laravel project for locale [{$locale}].\n";
        $prompt .= "Please generate the corresponding PHP array files or JSON entries for these keys.\n\n";
        $prompt .= "### Expected Structure:\n";
        $prompt .= "- For domain-prefixed keys (e.g. `domains/identity.field.user.name`), create or update `lang/{$locale}/domains/identity.php`.\n";
        $prompt .= "- Keys without a dot (e.g. `You're receiving this email`) belong in `lang/{$locale}.json`.\n";
        $prompt .= "- Use proper nested PHP arrays representing dot-notation keys.\n";
        $prompt .= "- Translate values naturally for target locale [{$locale}].\n\n";
        $prompt .= "### Missing Keys to Index:\n\n";

        foreach ($groupedByDomain as $domain => $keys) {
            $prompt .= "#### Domain/File: {$domain}\n";
            foreach ($keys as $key => $files) {
                $uniqueFiles = array_unique($files);
                $prompt .= "- `{$key}` (Used in: " . implode(', ', array_slice($uniqueFiles, 0, 2)) . ")\n";
            }
            $prompt .= "\n";
        }

        $prompt .= 'Please output the ready-to-use PHP array code for each file.';

        $this->line($prompt);
        $this->newLine();
        $this->info('===============================================================');
    }
}