<?php namespace Notes\CLI;

use Kash\HandleCacheTrait;
use Mcnd\CLI\Command;
use Mcnd\CLI\CommandStack;
use Mcnd\CLI\Option;
use Notes\ObjectResolver;

use Psr\SimpleCache\CacheInterface;
use RuntimeException, DirectoryIterator, Generator, Closure;

class CommandFetcher {
    use HandleCacheTrait;

    protected array $folderList;

    protected Closure $callback;

    public array $defaultMethods = [ 'GET', 'POST' ];

    protected array $annotations;

    public function __construct( ?array $folderList = null, ?array $annotations = null, ? CacheInterface $cache = null)
    {
        $this->cache = $cache;

        if ($folderList !== null) {
            $this->folderList = $folderList;
        }

        if ($annotations !== null) {
            $this->annotations = $annotations;
        }
        else {
            $this->annotations = [
                'object' => [ Attribute\Command::class, Attribute\Option::class ],
                'method' => [ Attribute\Command::class, Attribute\Option::class ],
            ];
        }
    }

    public function addFolder($folder) : void
    {
        $this->folderList[] = $folder;
    }

    public function setFolderList(array $list) : void
    {
        $this->folderList = $list;
    }

    public function scan(? array $folders = null) : Generator
    {
        foreach($folders ?: $this->folderList as $namespace => $folder) {
            if ( ! file_exists($folder) ) {
                throw new RuntimeException(sprintf("Folder `%s` can not be found or scanned", $folder));
            }

            foreach (new DirectoryIterator($folder) as $fileinfo) {
                if ( ! $fileinfo->isDot() ) {
                    if ( $fileinfo->isDir() ) {
                        foreach($this->scan([ "{$namespace}\\" . $fileinfo->getBasename() => $fileinfo->getPathname() ]) as $ns2 => $fi2) {
                            yield $ns2 => $fi2;
                        }
                    }
                    else {
                        yield $namespace => $fileinfo;
                    }
                }
            }
        }
    }

    public function compile() : CommandStack
    {
        return $this->handleCaching(substr(md5(serialize($this->annotations)), 0, 7), function() : CommandStack {
            $stack = new CommandStack();

            $classCmd = [];

            foreach($this->scan() as $namespace => $file) {
                if (  $file->getExtension() !== "php" ) {
                    continue;
                }

                $basename = $file->getBasename(".php");

                $class = $this->generateClassname($basename, $namespace);

                $objectResolver = new ObjectResolver($class, $this->cache);

                $attributes = $objectResolver->getAttributeListFromClassname( $this->annotations['object'], false ) ;

                $commandList = array_filter($attributes, fn($e) => $e instanceof Attribute\Command);

                ksort($commandList);

                if ($commandList) {
                    $fullCommand = [];

                    # Build full command token
                    foreach($commandList as $cmd) {
                        if ($cmd->command) {
                            $fullCommand[] = $cmd->command;
                        }
                    }

                    $fullCommand = implode(' ', $fullCommand);

                    $commandHeader = new Command(name: $fullCommand, description: end($commandList)->description);
                    $commandHeader->pushOption(array_filter($attributes, fn($e) => $e instanceof Attribute\Option));

                    $stack->append($commandHeader);

                    foreach($objectResolver->getAttributeListFromClassname( $this->annotations['method'], false ) as $method => $commands) {
                        if (is_array($commands) ) {
                            $commandAttribute = array_filter($commands, fn($e) => $e instanceof Attribute\Command)[0] ?? null;
                            $name = implode(' ', array_filter( [ $fullCommand, $commandAttribute->command ?? $method ]));
                            $commandFunction = new Command(name: $name, description: $commandAttribute->description, parent: $commandHeader, callback: "$class::$method");
                            $stack->append($commandFunction);

                            $commandFunction->pushOption(array_filter($commands, fn($e) => $e instanceof Attribute\Option));
                        }
                    }
                }
            }

            return $stack;
        });
    }

    protected function generateClassname($file, $namespace)
    {
        return "\\$namespace\\$file";
    }
}