<?php

namespace App\Filament\Pages;

use App\Services\Deployment\ChangeSetAnalyzer;
use App\Services\Deployment\DeploymentGuard;
use App\Services\Deployment\DeploymentPackageBuilder;
use App\Services\Deployment\DeploymentTargets;
use App\Services\Deployment\GitRepository;
use Filament\Forms\Components\Select;
use Filament\Forms\Components\TextInput;
use Filament\Forms\Concerns\InteractsWithForms;
use Filament\Forms\Contracts\HasForms;
use Filament\Notifications\Notification;
use Filament\Pages\Page;
use Filament\Schemas\Components\Grid;
use Filament\Schemas\Schema;
use Livewire\Attributes\Computed;
use RuntimeException;

/**
 * Deployment csomagoló: célkörnyezet, commit-tartomány, diff-előnézet és csomagolás.
 *
 * Az oldal a git történetet olvassa, és a kijelölt tartományból egy időbélyeges mappát
 * állít elő a config('deployment.output_path') alatt - a repón kívülre nem ír.
 *
 * A hozzáférést a DeploymentGuard dönti el (env kapcsoló + stage whitelist +
 * developer szerep + feature flag), és a mount()-on kívül minden akció elején
 * újra lefut - a felület elrejtése önmagában nem védelem.
 */
class DeploymentPackage extends Page implements HasForms
{
    use InteractsWithForms;

    protected static string|\BackedEnum|null $navigationIcon = 'heroicon-o-rocket-launch';

    protected string $view = 'filament.pages.deployment-package';

    protected static ?string $title = 'Deployment csomagoló';

    protected static ?string $navigationLabel = 'Deployment csomagoló';

    protected static bool $shouldRegisterNavigation = false;

    /** @var array<string, mixed>|null */
    public ?array $data = [];

    public ?string $fromCommit = null;

    public ?string $toCommit = null;

    public ?string $gitError = null;

    /** @var array<int, string> a felületen kézzel kivett fájlok */
    public array $skippedPaths = [];

    /** @var array<string, mixed>|null az utoljára elkészített csomag adatai */
    public ?array $lastPackage = null;

    public static function canAccess(): bool
    {
        return app(DeploymentGuard::class)->isAllowed(auth()->user());
    }

    public function mount(): void
    {
        app(DeploymentGuard::class)->ensureAllowed(auth()->user());

        /** @var array<int, int> $limits */
        $limits = (array) config('deployment.commit_limits', [50]);

        $this->form->fill([
            'target' => app(DeploymentTargets::class)->defaultKey(),
            'branch' => $this->defaultBranch(),
            'limit' => $limits[0] ?? 50,
            'search' => null,
        ]);
    }

    public function form(Schema $form): Schema
    {
        /** @var array<int, int> $limits */
        $limits = (array) config('deployment.commit_limits', [50]);

        return $form
            ->schema([
                Grid::make(4)
                    ->schema([
                        Select::make('target')
                            ->label('Célkörnyezet')
                            ->options(app(DeploymentTargets::class)->options())
                            ->required()
                            ->live()
                            ->helperText(fn (): ?string => $this->target()['remote_path'] ?? null),
                        Select::make('branch')
                            ->label('Branch')
                            ->options($this->branchOptions())
                            ->required()
                            ->searchable()
                            ->live()
                            ->afterStateUpdated(fn () => $this->clearRange()),
                        Select::make('limit')
                            ->label('Commitok száma')
                            ->options(array_combine($limits, $limits))
                            ->required()
                            ->live(),
                        TextInput::make('search')
                            ->label('Keresés')
                            ->placeholder('pl. árlista, migráció, szerző')
                            ->helperText('A commit üzenetében (a törzsben is), a szerzőben és a hashben keres, a betöltött listán belül.')
                            ->live(debounce: 400),
                    ]),
            ])
            ->statePath('data');
    }

    public function selectFrom(string $hash): void
    {
        app(DeploymentGuard::class)->ensureAllowed(auth()->user());

        $this->fromCommit = $this->resolveOrWarn($hash);
    }

    public function selectTo(string $hash): void
    {
        app(DeploymentGuard::class)->ensureAllowed(auth()->user());

        $this->toCommit = $this->resolveOrWarn($hash);
    }

    public function swapRange(): void
    {
        app(DeploymentGuard::class)->ensureAllowed(auth()->user());

        [$this->fromCommit, $this->toCommit] = [$this->toCommit, $this->fromCommit];
    }

    public function clearRange(): void
    {
        $this->fromCommit = null;
        $this->toCommit = null;
        $this->skippedPaths = [];
    }

    /**
     * Egy fájl kézi ki-/visszavétele a csomagból.
     */
    public function toggleFile(string $path): void
    {
        app(DeploymentGuard::class)->ensureAllowed(auth()->user());

        $this->skippedPaths = in_array($path, $this->skippedPaths, true)
            ? array_values(array_diff($this->skippedPaths, [$path]))
            : array_merge($this->skippedPaths, [$path]);
    }

    /**
     * A csomag előállítása a kijelölt tartományból.
     */
    public function createPackage(): void
    {
        app(DeploymentGuard::class)->ensureAllowed(auth()->user());

        if (! $this->fromCommit || ! $this->toCommit) {
            Notification::make()
                ->title('Nincs kijelölt tartomány')
                ->body('Válassz egy kezdő és egy záró commitot.')
                ->danger()
                ->send();

            return;
        }

        try {
            $this->lastPackage = app(DeploymentPackageBuilder::class)->build(
                (string) ($this->data['target'] ?? ''),
                (string) ($this->data['branch'] ?? ''),
                $this->fromCommit,
                $this->toCommit,
                $this->skippedPaths,
                auth()->user()?->email,
            );
        } catch (RuntimeException $exception) {
            Notification::make()
                ->title('A csomag nem készült el')
                ->body($exception->getMessage())
                ->danger()
                ->persistent()
                ->send();

            return;
        }

        Notification::make()
            ->title('A csomag elkészült')
            ->body(sprintf(
                '%d fájl a(z) %s mappában.',
                $this->lastPackage['counts']['copied'],
                $this->lastPackage['name'],
            ))
            ->success()
            ->send();
    }

    /**
     * @return array{key:string, label:string, domain:string, remote_path:string, expected_branch:?string}|null
     */
    public function target(): ?array
    {
        return app(DeploymentTargets::class)->find($this->data['target'] ?? null);
    }

    /**
     * @return array<int, array{hash:string, short:string, author:string, date:string, subject:string, body:string, file_count:?int}>
     */
    #[Computed]
    public function commits(): array
    {
        $branch = $this->data['branch'] ?? null;

        if (! $branch) {
            return [];
        }

        try {
            $commits = app(GitRepository::class)->commits($branch, (int) ($this->data['limit'] ?? 50));
        } catch (RuntimeException $exception) {
            $this->gitError = $exception->getMessage();

            return [];
        }

        $search = trim((string) ($this->data['search'] ?? ''));

        if ($search === '') {
            return $commits;
        }

        $needle = mb_strtolower($search);

        return array_values(array_filter(
            $commits,
            fn (array $commit): bool => str_contains(
                mb_strtolower(implode(' ', [$commit['subject'], $commit['body'], $commit['author'], $commit['hash']])),
                $needle,
            ),
        ));
    }

    /**
     * A kijelölt tartomány elemzése, vagy null, ha még nincs két commit kiválasztva.
     *
     * @return array{
     *     files: array<int, array{status:string, path:string, old_path:?string, excluded:bool, action:string}>,
     *     copied: array<int, string>,
     *     deleted: array<int, string>,
     *     counts: array{total:int, copied:int, deleted:int, excluded:int},
     *     warnings: array<int, array{level:string, title:string, body:string}>
     * }|null
     */
    #[Computed]
    public function changeSet(): ?array
    {
        if (! $this->fromCommit || ! $this->toCommit) {
            return null;
        }

        $repository = app(GitRepository::class);

        try {
            $changedFiles = $repository->changedFiles($this->fromCommit, $this->toCommit);
        } catch (RuntimeException $exception) {
            $this->gitError = $exception->getMessage();

            return null;
        }

        $changeSet = app(ChangeSetAnalyzer::class)->analyze(
            $changedFiles,
            $this->target(),
            $this->data['branch'] ?? null,
        );

        if ($this->fromCommit === $this->toCommit) {
            array_unshift($changeSet['warnings'], [
                'level' => 'warning',
                'title' => 'Azonos commitok',
                'body' => 'A kezdő és a záró commit ugyanaz, így a tartomány üres.',
            ]);
        } elseif (! $repository->isAncestor($this->fromCommit, $this->toCommit)) {
            array_unshift($changeSet['warnings'], [
                'level' => 'danger',
                'title' => 'Fordított vagy szétágazó tartomány',
                'body' => 'A kezdő commit nem őse a zárónak, ezért a lista nem a "mi került bele azóta" kérdésre válaszol. Ellenőrizd a sorrendet (Csere gomb), vagy azt, hogy ugyanazon az ágon vagy-e.',
            ]);
        }

        return $changeSet;
    }

    /**
     * A kijelölt tartományba eső commitok - csak a lista kiemeléséhez.
     *
     * @return array<int, string>
     */
    #[Computed]
    public function highlightedHashes(): array
    {
        if (! $this->fromCommit || ! $this->toCommit) {
            return array_values(array_filter([$this->fromCommit, $this->toCommit]));
        }

        $hashes = array_column($this->commits(), 'hash');
        $fromIndex = array_search($this->fromCommit, $hashes, true);
        $toIndex = array_search($this->toCommit, $hashes, true);

        if ($fromIndex === false || $toIndex === false) {
            return array_values(array_filter([$this->fromCommit, $this->toCommit]));
        }

        // A lista fentről lefelé a legfrissebbtől halad, tehát a záró commit van előrébb.
        [$start, $end] = $fromIndex <= $toIndex ? [$fromIndex, $toIndex] : [$toIndex, $fromIndex];

        return array_slice($hashes, $start, $end - $start + 1);
    }

    /**
     * @return array<string, string>
     */
    public function branchOptions(): array
    {
        try {
            $branches = app(GitRepository::class)->branches();
        } catch (RuntimeException $exception) {
            $this->gitError = $exception->getMessage();

            return [];
        }

        return array_combine($branches, $branches) ?: [];
    }

    public function isRepositoryAvailable(): bool
    {
        return app(GitRepository::class)->isAvailable();
    }

    private function defaultBranch(): ?string
    {
        $repository = app(GitRepository::class);
        $current = $repository->currentBranch();

        if ($current) {
            return $current;
        }

        return $this->branchOptions() === [] ? null : array_key_first($this->branchOptions());
    }

    private function resolveOrWarn(string $hash): ?string
    {
        $resolved = app(GitRepository::class)->resolveCommit($hash);

        if (! $resolved) {
            Notification::make()
                ->title('Ismeretlen commit')
                ->body('A kiválasztott commit nem található a repóban.')
                ->danger()
                ->send();

            return null;
        }

        return $resolved;
    }
}