<?php

namespace App\Services\Manage;

use App\Enums\OrderChannel;
use App\Enums\OrderStatus;
use App\Enums\PriceType;
use App\Models\Customer;
use App\Models\Order;
use App\Models\OrderItem;
use App\Models\Product;
use App\Models\ProductPrice;
use App\Models\ProductVariant;
use App\Models\User;
use App\Services\System\PushNotificationService;
use App\Services\System\Setting\MarketplaceService;
use App\Support\Media\MediaPresenter;
use Illuminate\Contracts\Pagination\LengthAwarePaginator;
use Illuminate\Database\Eloquent\Builder;
use Illuminate\Database\Eloquent\Collection as EloquentCollection;
use Illuminate\Support\Collection;
use Illuminate\Support\Facades\DB;
use Illuminate\Validation\ValidationException;

class OrderService
{
    public function __construct(
        private readonly MarketplaceService $marketplaceService,
        private readonly PushNotificationService $pushNotificationService,
    ) {}

    /**
     * @param  array{search: string, sort: string, direction: 'asc'|'desc'}  $tableQuery
     */
    public function paginateForIndex(array $tableQuery, User $user): LengthAwarePaginator
    {
        $query = Order::query()
            ->with([
                'customer:id,name',
                'createdBy.profile',
                'items.productVariant.product:id,name',
                'items.productVariant:id,product_id,name',
            ])
            ->when($user->hasRole('marketing'), fn (Builder $query) => $query->where('marketing_id', $user->id))
            ->when($tableQuery['search'] !== '', function (Builder $query) use ($tableQuery): void {
                $search = $tableQuery['search'];
                $query->where(function (Builder $query) use ($search): void {
                    $query->where('order_number', 'like', "%{$search}%")
                        ->orWhere('notes', 'like', "%{$search}%")
                        ->orWhereHas('customer', fn (Builder $query) => $query->where('name', 'like', "%{$search}%"))
                        ->orWhereHas('items.productVariant', function (Builder $query) use ($search): void {
                            $query->where('name', 'like', "%{$search}%")
                                ->orWhereHas('product', fn (Builder $query) => $query->where('name', 'like', "%{$search}%"));
                        });
                });
            });

        $this->applySorting($query, $tableQuery['sort'], $tableQuery['direction']);

        return $query
            ->paginate(10)
            ->withQueryString()
            ->through(function (Order $order) use ($user) {
                $actions = collect($order->status->availableActions())
                    ->filter(fn (array $action) => $user->can($action['permission']))
                    ->values()
                    ->all();

                $order->setAttribute('available_actions', $actions);
                $order->setAttribute('is_editable', $order->status->isEditable());

                return $order;
            });
    }

    /**
     * @return list<array{value: int, label: string}>
     */
    public function customerOptions(): array
    {
        return Customer::query()
            ->orderBy('name')
            ->get(['id', 'name'])
            ->map(fn (Customer $customer) => [
                'value' => $customer->id,
                'label' => $customer->name,
            ])
            ->all();
    }

    /**
     * @return list<array{value: int, label: string}>
     */
    public function marketingOptions(): array
    {
        return User::query()
            ->active()
            ->whereHas('roles', fn ($q) => $q->where('name', 'marketing'))
            ->with('profile:user_id,full_name')
            ->orderBy('username')
            ->get(['id', 'username'])
            ->map(fn (User $user) => [
                'value' => $user->id,
                'label' => $user->profile?->full_name ?? $user->username,
            ])
            ->all();
    }

    /**
     * @return list<array{value: string, label: string}>
     */
    public function storePriceTypeOptions(): array
    {
        return collect(PriceType::cases())
            ->reject(fn (PriceType $type) => in_array($type, [PriceType::SHOPEE, PriceType::TIKTOK], true))
            ->map(fn (PriceType $type) => [
                'value' => $type->value,
                'label' => $type->label(),
            ])
            ->values()
            ->all();
    }

    /**
     * @return Collection<int, Product>
     */
    public function catalogItems(?Order $order = null, ?User $user = null): Collection
    {
        $orderVariantIds = $order
            ? $order->items()->pluck('product_variant_id')->all()
            : ($user ? $this->draftItemsQuery($user)->pluck('product_variant_id')->all() : []);

        return Product::query()
            ->with([
                'variants' => fn ($query) => $query
                    ->with(['prices' => fn ($query) => $query->orderBy('type'), 'media'])
                    ->orderBy('created_at'),
            ])
            ->where(function (Builder $query) use ($orderVariantIds): void {
                $query->where('is_active', true);

                if ($orderVariantIds !== []) {
                    $query->orWhereHas(
                        'variants',
                        fn (Builder $query) => $query->whereIn('id', $orderVariantIds),
                    );
                }
            })
            ->orderBy('name')
            ->get()
            ->each(function (Product $product): void {
                $product->variants->each(function (ProductVariant $variant): void {
                    $variant->setAttribute(
                        'images',
                        MediaPresenter::collection($variant, 'images'),
                    );
                });
            });
    }

    public function findForEdit(Order $order): Order
    {
        $order->load([
            'items.productVariant.product:id,name',
            'items.productVariant.prices',
            'items.productVariant.media',
        ]);

        $order->items->each(function (OrderItem $item): void {
            $variant = $item->productVariant;

            if ($variant) {
                $item->setAttribute('product_name', $variant->product?->name);
                $item->setAttribute('variant_name', $variant->name);
                $variant->setAttribute(
                    'images',
                    MediaPresenter::collection($variant, 'images'),
                );
            }
        });

        return $order;
    }

    /**
     * @return list<array<string, mixed>>
     */
    public function draftItemsForUser(User $user): array
    {
        return $this->draftItemsQuery($user)
            ->with([
                'productVariant.product:id,name',
                'productVariant.media',
            ])
            ->get()
            ->map(fn (OrderItem $item) => $this->presentDraftItem($item))
            ->values()
            ->all();
    }

    /**
     * @param  array<string, mixed>  $validated
     * @return array<string, mixed>
     */
    public function syncDraftItem(array $validated, User $user): array
    {
        $priceType = PriceType::from($validated['price_type']);
        $variant = ProductVariant::query()->findOrFail($validated['product_variant_id']);
        $price = ProductPrice::query()
            ->where('variant_id', $variant->id)
            ->where('type', $priceType)
            ->first();

        if ($price === null) {
            throw ValidationException::withMessages([
                'product_variant_id' => 'Harga untuk tipe harga ini belum diatur.',
            ]);
        }

        $quantity = (int) $validated['quantity'];
        if ($quantity > $variant->stock) {
            throw ValidationException::withMessages([
                'quantity' => "Stok tidak mencukupi. Stok saat ini: {$variant->stock} pcs.",
            ]);
        }

        $unitPrice = (int) $price->price;
        $subtotal = $unitPrice * $quantity;

        $item = OrderItem::query()->updateOrCreate(
            [
                'user_id' => $user->id,
                'product_variant_id' => $variant->id,
                'order_id' => null,
            ],
            [
                'quantity' => $quantity,
                'unit_price' => $unitPrice,
                'subtotal' => $subtotal,
            ],
        );

        $item->load([
            'productVariant.product:id,name',
            'productVariant.media',
        ]);

        return $this->presentDraftItem($item);
    }

    public function removeDraftItem(User $user, ProductVariant $productVariant): void
    {
        OrderItem::query()
            ->whereNull('order_id')
            ->where('user_id', $user->id)
            ->where('product_variant_id', $productVariant->id)
            ->delete();
    }

    /**
     * @return list<array<string, mixed>>
     */
    public function resyncDraftPrices(User $user, string $priceTypeValue): array
    {
        $priceType = PriceType::from($priceTypeValue);

        $items = $this->draftItemsQuery($user)
            ->with([
                'productVariant.product:id,name',
                'productVariant.media',
            ])
            ->get();

        foreach ($items as $item) {
            $price = ProductPrice::query()
                ->where('variant_id', $item->product_variant_id)
                ->where('type', $priceType)
                ->first();

            if ($price === null) {
                $item->delete();

                continue;
            }

            $unitPrice = (int) $price->price;
            $item->unit_price = $unitPrice;
            $item->subtotal = $unitPrice * $item->quantity;
            $item->save();
        }

        return $this->draftItemsForUser($user);
    }

    /**
     * @param  array<string, mixed>  $validated
     */
    public function create(array $validated, User $user): Order
    {
        $order = DB::transaction(function () use ($validated, $user): Order {
            $priceType = $this->resolvePriceType($validated['channel'], $validated['price_type']);

            /** @var EloquentCollection<int, OrderItem> $draftItems */
            $draftItems = $this->draftItemsQuery($user)
                ->lockForUpdate()
                ->get();

            if ($draftItems->isEmpty()) {
                throw ValidationException::withMessages([
                    'items' => 'Tambahkan minimal satu produk ke keranjang.',
                ]);
            }

            $this->applyDraftPrices($draftItems, $priceType);

            $subtotal = $draftItems->sum('subtotal');
            $discount = (int) ($validated['discount'] ?? 0);
            $totalAmount = max($subtotal - $discount, 0);
            $channel = OrderChannel::from($validated['channel']);

            $order = Order::create([
                'customer_id' => $validated['customer_id'] ?? null,
                'marketing_id' => $validated['marketing_id'] ?? null,
                'channel' => $channel,
                'price_type' => $priceType,
                'status' => OrderStatus::PENDING,
                'created_by_id' => $user->id,
                'subtotal' => $subtotal,
                'discount' => $discount,
                'marketplace_settings_snapshot' => $this->marketplaceService->buildOrderSnapshot(
                    $channel,
                    $totalAmount,
                    $this->lineItemsForSnapshot($draftItems),
                ),
                'total_amount' => $totalAmount,
                'notes' => $validated['notes'] ?? null,
            ]);

            foreach ($draftItems as $item) {
                $variant = ProductVariant::query()->with('product')->lockForUpdate()->find($item->product_variant_id);
                if ($variant === null) {
                    throw ValidationException::withMessages([
                        'items' => 'Varian produk tidak ditemukan.',
                    ]);
                }
                if ($variant->stock < $item->quantity) {
                    throw ValidationException::withMessages([
                        'items' => "Stok produk {$variant->product->name} ({$variant->name}) tidak mencukupi. Stok saat ini: {$variant->stock} pcs.",
                    ]);
                }
                $item->order_id = $order->id;
                $item->save();
                $this->decrementStock($item);
            }

            return $order;
        });

        $this->pushNotificationService->sendToRoles(
            '📦 Pesanan Baru',
            "Pesanan baru {$order->order_number} senilai {$order->total_amount_formatted} telah dibuat oleh {$user->profile?->full_name}.",
            ['owner', 'developer'],
            '/admin/manage/orders',
        );

        return $order;
    }

    /**
     * @param  array<string, mixed>  $validated
     */
    public function update(Order $order, array $validated): void
    {
        if (! $order->status->isEditable()) {
            throw ValidationException::withMessages([
                'status' => 'Pesanan tidak dapat diubah.',
            ]);
        }

        DB::transaction(function () use ($order, $validated): void {
            $order->load('items');

            foreach ($order->items as $item) {
                $this->incrementStock($item);
            }

            $order->items()->delete();

            $priceType = $this->resolvePriceType($validated['channel'], $validated['price_type']);
            $lineItems = $this->buildLineItems($validated['items'], $priceType);
            $subtotal = array_sum(array_column($lineItems, 'subtotal'));
            $discount = (int) ($validated['discount'] ?? 0);
            $totalAmount = max($subtotal - $discount, 0);
            $channel = OrderChannel::from($validated['channel']);

            $order->customer_id = $validated['customer_id'] ?? null;
            $order->marketing_id = $validated['marketing_id'] ?? null;
            $order->channel = $channel;
            $order->price_type = $priceType;
            $order->subtotal = $subtotal;
            $order->discount = $discount;
            $order->marketplace_settings_snapshot = $this->marketplaceService->buildOrderSnapshot(
                $channel,
                $totalAmount,
                $this->lineItemsForSnapshot($lineItems),
            );
            $order->total_amount = $totalAmount;
            $order->notes = $validated['notes'] ?? null;
            $order->save();

            foreach ($lineItems as $itemData) {
                $variant = ProductVariant::query()->with('product')->lockForUpdate()->find($itemData['product_variant_id']);
                if ($variant === null) {
                    throw ValidationException::withMessages([
                        'items' => 'Varian produk tidak ditemukan.',
                    ]);
                }
                if ($variant->stock < $itemData['quantity']) {
                    throw ValidationException::withMessages([
                        'items' => "Stok produk {$variant->product->name} ({$variant->name}) tidak mencukupi. Stok saat ini: {$variant->stock} pcs.",
                    ]);
                }
                $orderItem = $order->items()->create($itemData);
                $this->decrementStock($orderItem);
            }
        });

        $this->pushNotificationService->sendToRoles(
            '✏️ Pesanan Diperbarui',
            "Pesanan {$order->order_number} senilai {$order->total_amount_formatted} telah diperbarui.",
            ['owner', 'developer'],
            '/admin/manage/orders',
        );
    }

    public function delete(Order $order): void
    {
        $orderNumber = $order->order_number;
        $totalAmount = $order->total_amount;

        DB::transaction(function () use ($order): void {
            $order->load('items');

            if ($order->status->isEditable()) {
                foreach ($order->items as $item) {
                    $this->incrementStock($item);
                }
            }

            $order->items()->delete();
            $order->delete();
        });

        $this->pushNotificationService->sendToRoles(
            '🗑️ Pesanan Dihapus',
            "Pesanan {$orderNumber} senilai {$order->total_amount_formatted} telah dihapus.",
            ['owner', 'developer'],
            '/admin/manage/orders',
        );
    }

    public function transitionStatus(Order $order, OrderStatus $status): void
    {
        if (! $order->status->canTransitionTo($status)) {
            throw ValidationException::withMessages([
                'status' => 'Status pesanan tidak dapat diubah.',
            ]);
        }

        DB::transaction(function () use ($order, $status): void {
            if ($status === OrderStatus::CANCELLED) {
                $order->load('items');

                foreach ($order->items as $item) {
                    $this->incrementStock($item);
                }
            }

            $order->status = $status;
            $order->save();
        });

        $this->pushNotificationService->sendToRoles(
            '📦 Status Pesanan Diubah',
            "Pesanan {$order->order_number} diubah statusnya menjadi {$status->label()}.",
            ['owner', 'developer'],
            '/admin/manage/orders',
        );
    }

    /**
     * @param  list<array{product_variant_id: int, quantity: int|string}>  $items
     * @return list<array{product_variant_id: int, quantity: int, unit_price: int, subtotal: int}>
     */
    private function buildLineItems(array $items, PriceType $priceType): array
    {
        return collect($items)
            ->map(function (array $itemData, int $index) use ($priceType) {
                $variant = ProductVariant::query()->find($itemData['product_variant_id']);

                if ($variant === null) {
                    throw ValidationException::withMessages([
                        "items.{$index}.product_variant_id" => 'Varian produk tidak ditemukan.',
                    ]);
                }

                $price = ProductPrice::query()
                    ->where('variant_id', $variant->id)
                    ->where('type', $priceType)
                    ->first();

                if ($price === null) {
                    throw ValidationException::withMessages([
                        "items.{$index}.product_variant_id" => 'Harga untuk tipe harga ini belum diatur.',
                    ]);
                }

                $quantity = (int) $itemData['quantity'];

                if ($quantity < 1) {
                    throw ValidationException::withMessages([
                        "items.{$index}.quantity" => 'Jumlah minimal 1 pcs.',
                    ]);
                }

                $unitPrice = (int) $price->price;
                $subtotal = $unitPrice * $quantity;

                return [
                    'product_variant_id' => $variant->id,
                    'quantity' => $quantity,
                    'unit_price' => $unitPrice,
                    'subtotal' => $subtotal,
                ];
            })
            ->all();
    }

    private function resolvePriceType(string $channel, string $priceType): PriceType
    {
        $channelEnum = OrderChannel::from($channel);
        $priceTypeEnum = PriceType::from($priceType);

        $defaultPriceType = $channelEnum->defaultPriceType();

        if ($defaultPriceType !== null && $priceTypeEnum !== $defaultPriceType) {
            throw ValidationException::withMessages([
                'price_type' => 'Tipe harga tidak sesuai dengan channel pesanan.',
            ]);
        }

        if ($channelEnum === OrderChannel::STORE && in_array($priceTypeEnum, [PriceType::SHOPEE, PriceType::TIKTOK], true)) {
            throw ValidationException::withMessages([
                'price_type' => 'Tipe harga marketplace tidak dapat digunakan untuk channel toko.',
            ]);
        }

        return $priceTypeEnum;
    }

    /**
     * @return Builder<OrderItem>
     */
    private function draftItemsQuery(User $user): Builder
    {
        return OrderItem::query()
            ->whereNull('order_id')
            ->where('user_id', $user->id);
    }

    /**
     * @return array<string, mixed>
     */
    private function presentDraftItem(OrderItem $item): array
    {
        $variant = $item->productVariant;

        return [
            'product_variant_id' => $item->product_variant_id,
            'product_name' => $variant?->product?->name ?? '',
            'variant_name' => $variant?->name ?? '',
            'quantity' => (string) $item->quantity,
            'unit_price' => $item->unit_price,
            'images' => $variant ? MediaPresenter::collection($variant, 'images') : [],
        ];
    }

    /**
     * @param  EloquentCollection<int, OrderItem>  $items
     */
    private function applyDraftPrices(EloquentCollection $items, PriceType $priceType): void
    {
        foreach ($items as $index => $item) {
            $price = ProductPrice::query()
                ->where('variant_id', $item->product_variant_id)
                ->where('type', $priceType)
                ->first();

            if ($price === null) {
                throw ValidationException::withMessages([
                    "items.{$index}.product_variant_id" => 'Harga untuk tipe harga ini belum diatur.',
                ]);
            }

            $unitPrice = (int) $price->price;
            $item->unit_price = $unitPrice;
            $item->subtotal = $unitPrice * $item->quantity;
            $item->save();
        }
    }

    private function decrementStock(OrderItem $item): void
    {
        ProductVariant::query()
            ->whereKey($item->product_variant_id)
            ->decrement('stock', $item->quantity);
    }

    private function incrementStock(OrderItem $item): void
    {
        ProductVariant::query()
            ->whereKey($item->product_variant_id)
            ->increment('stock', $item->quantity);
    }

    /**
     * @param  EloquentCollection<int, OrderItem>|list<array{quantity: int, subtotal: int}>  $items
     * @return list<array{quantity: int, subtotal: int}>
     */
    private function lineItemsForSnapshot(EloquentCollection|array $items): array
    {
        return collect($items)
            ->map(fn (OrderItem|array $item) => [
                'quantity' => (int) (is_array($item) ? $item['quantity'] : $item->quantity),
                'subtotal' => (int) (is_array($item) ? $item['subtotal'] : $item->subtotal),
            ])
            ->values()
            ->all();
    }

    private function applySorting(Builder $query, string $sort, string $direction): void
    {
        if (in_array($sort, ['created_at', 'total_amount', 'discount', 'subtotal', 'order_number'], true)) {
            $query->orderBy($sort, $direction);

            return;
        }

        $query->latest();
    }
}