<?php

namespace App\Services\Store;

use App\Models\Household;
use App\Models\PartnerStore;
use App\Models\QrCode;
use App\Models\QrCodeBatch;
use App\Models\StoreInventory;
use App\Models\StorePurchase;
use App\Models\StoreSale;
use App\Notifications\CodesPurchased;
use App\Services\Qr\BatchGenerator;
use App\States\QrCode\Active;
use App\States\QrCode\Allocated;
use App\States\QrCode\Unassigned;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Notification;

class StoreOperations
{
    public function __construct(private readonly BatchGenerator $batches) {}

    /**
     * Issue a new wholesale batch to a store. Generates a fresh batch
     * targeted at the store, marks codes as `allocated` to that store,
     * tops up the store's inventory, and records a StorePurchase.
     */
    public function issueWholesale(
        PartnerStore $store,
        int $quantity,
        int $wholesalePriceCentavos,
        ?\DateTimeInterface $paidAt = null,
    ): StorePurchase {
        return DB::transaction(function () use ($store, $quantity, $wholesalePriceCentavos, $paidAt) {
            $batch = $this->batches->generate(
                quantity: $quantity,
                purpose: QrCodeBatch::PURPOSE_STORE,
                targetArea: null,
                targetStoreId: $store->id,
                createdBy: null,
                notes: "Wholesale to store {$store->business_name}",
            );

            $now = now();
            QrCode::query()
                ->where('batch_id', $batch->id)
                ->where('status', Unassigned::$name)
                ->update([
                    'status' => Allocated::$name,
                    'assigned_to_store_id' => $store->id,
                    'allocated_at' => $now,
                    'updated_at' => $now,
                ]);

            $purchase = StorePurchase::create([
                'store_id' => $store->id,
                'batch_id' => $batch->id,
                'quantity' => $quantity,
                'wholesale_price_centavos' => $wholesalePriceCentavos,
                'paid_at' => $paidAt ?? $now,
            ]);

            $inventory = StoreInventory::firstOrCreate(['store_id' => $store->id], ['current_code_balance' => 0]);
            $inventory->forceFill([
                'current_code_balance' => $inventory->current_code_balance + $quantity,
                'last_updated_at' => $now,
            ])->save();

            return $purchase;
        });
    }

    /**
     * Sell N codes from a store's inventory to a resident's household.
     * Codes transition allocated -> active and reassign household.
     */
    public function sellToHousehold(
        PartnerStore $store,
        Household $household,
        int $quantity,
        int $retailPricePerCodeCentavos,
    ): StoreSale {
        return DB::transaction(function () use ($store, $household, $quantity, $retailPricePerCodeCentavos) {
            $codeIds = QrCode::query()
                ->where('assigned_to_store_id', $store->id)
                ->where('status', Allocated::$name)
                ->orderBy('id')
                ->limit($quantity)
                ->lockForUpdate()
                ->pluck('id');

            if ($codeIds->count() < $quantity) {
                throw new \DomainException("Store has only {$codeIds->count()} codes available");
            }

            $now = now();
            QrCode::whereIn('id', $codeIds)->update([
                'status' => Active::$name,
                'assigned_to_household_id' => $household->id,
                'assigned_to_store_id' => null,
                'activated_at' => $now,
                'updated_at' => $now,
            ]);

            $totalRetail = $retailPricePerCodeCentavos * $quantity;
            $commission = (int) round($totalRetail * ($store->commission_rate_percent / 100));

            $sale = StoreSale::create([
                'store_id' => $store->id,
                'household_id' => $household->id,
                'quantity' => $quantity,
                'retail_price_centavos' => $totalRetail,
                'commission_centavos' => $commission,
                'sold_at' => $now,
            ]);

            $inventory = StoreInventory::firstOrCreate(['store_id' => $store->id], ['current_code_balance' => 0]);
            $inventory->forceFill([
                'current_code_balance' => max(0, $inventory->current_code_balance - $quantity),
                'last_updated_at' => $now,
            ])->save();

            // Notify the household head — fire after commit so the receiver
            // sees the persisted state.
            if ($household->head) {
                Notification::send(
                    $household->head,
                    new CodesPurchased($quantity, $totalRetail, $store->business_name),
                );
            }

            return $sale;
        });
    }
}