<?php

namespace App\Services\Pos;

use App\Models\Pos\ProSubscription;
use App\Models\PosCategory;
use App\Models\PosDevice;
use App\Models\PosLocation;
use App\Models\PosMember;
use App\Models\PosPayment;
use App\Models\PosProduct;
use App\Models\PosSale;
use App\Models\PosSaleLine;
use App\Models\PosStation;
use App\Models\User;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Str;

class DemoSeeder
{
    /** @var array<string, array{locations: int, products_per_location: int, stations: int, sales_per_location: int}> */
    private const VOLUMES = [
        'free' => [
            'locations' => 1,
            'products_per_location' => 40,
            'stations' => 0,
            'sales_per_location' => 12,
        ],
        'pro' => [
            'locations' => 3,
            'products_per_location' => 55,
            'stations' => 3,
            'sales_per_location' => 25,
        ],
        'enterprise' => [
            'locations' => 5,
            'products_per_location' => 70,
            'stations' => 5,
            'sales_per_location' => 40,
        ],
    ];

    private const PRODUCT_NAMES = [
        'Bottled Water', 'Soft Drink', 'Rice Pack', 'Chicken Wrap', 'Veggie Bowl',
        'Coffee', 'Tea', 'Pastry', 'Sandwich', 'Energy Bar',
        'Phone Charger', 'USB Cable', 'Notebook', 'Pen Set', 'Tote Bag',
        'Shampoo', 'Soap', 'Toothpaste', 'Detergent', 'Tissue Pack',
    ];

    /**
     * @return array{user: User, plan: string, counts: array<string, int>}
     */
    public function seed(string $identity, string $plan, bool $reset = false): array
    {
        $plan = $this->normalizePlan($plan);
        $user = $this->resolveUser($identity);

        if ($reset) {
            $this->resetForOwner($user->public_id);
        }

        $this->assignPlan($user, $plan);

        $volumes = self::VOLUMES[$plan];
        $stations = $this->seedStations($user->public_id, $volumes['stations']);
        $categories = $this->seedCategories($user->public_id);
        $locations = $this->seedLocations($user->public_id, $volumes['locations']);

        foreach ($locations as $index => $location) {
            $this->seedRegister($user->public_id, $location, $index === 0);
            $products = $this->seedProducts(
                $user->public_id,
                $location,
                $categories,
                $stations,
                $volumes['products_per_location'],
            );
            $this->seedCashSales(
                $user->public_id,
                $location,
                $products,
                $volumes['sales_per_location'],
            );
        }

        if ($plan !== 'free') {
            $this->seedTeam($user);
        }

        return [
            'user' => $user,
            'plan' => $plan,
            'counts' => [
                'locations' => PosLocation::owned($user->public_id)->count(),
                'products' => PosProduct::owned($user->public_id)->count(),
                'stations' => PosStation::owned($user->public_id)->count(),
                'sales' => PosSale::owned($user->public_id)->count(),
                'registers' => PosDevice::owned($user->public_id)->where('type', 'register')->count(),
            ],
        ];
    }

    public function resolveUser(string $identity): User
    {
        $identity = trim($identity);
        $user = User::query()
            ->where(function ($q) use ($identity) {
                $q->where('email', $identity)->orWhere('public_id', $identity);
            })
            ->first();

        if ($user) {
            return $user;
        }

        $email = str_contains($identity, '@') ? $identity : $identity.'@demo.ladill.local';
        $publicId = str_contains($identity, '@') ? (string) Str::uuid() : $identity;

        return User::query()->create([
            'public_id' => $publicId,
            'name' => 'Demo User',
            'email' => $email,
            'password' => bcrypt('password'),
            'email_verified_at' => now(),
        ]);
    }

    public function assignPlan(User $user, string $plan): void
    {
        if ($plan === 'free') {
            ProSubscription::query()->where('user_id', $user->id)->delete();

            return;
        }

        $price = $plan === ProSubscription::PLAN_ENTERPRISE
            ? (int) config('pos.plans.enterprise.price_minor', 249000)
            : (int) config('pos.plans.pro.price_minor', config('pos.pro.price_minor', 179000));

        ProSubscription::updateOrCreate(
            ['user_id' => $user->id],
            [
                'plan' => $plan,
                'status' => ProSubscription::STATUS_ACTIVE,
                'price_minor' => $price,
                'currency' => (string) config('pos.pro.currency', 'GHS'),
                'auto_renew' => false,
                'started_at' => now(),
                'current_period_end' => now()->addYear(),
                'last_charged_at' => now(),
                'canceled_at' => null,
                'last_reference' => 'demo-pos-'.$plan.'-'.$user->id,
                'last_error' => null,
            ],
        );
    }

    public function resetForOwner(string $ownerRef): void
    {
        DB::transaction(function () use ($ownerRef) {
            $saleIds = PosSale::owned($ownerRef)->pluck('id');
            if ($saleIds->isNotEmpty()) {
                $lineIds = PosSaleLine::query()->whereIn('pos_sale_id', $saleIds)->pluck('id');
                if ($lineIds->isNotEmpty() && DB::getSchemaBuilder()->hasTable('pos_sale_line_modifiers')) {
                    DB::table('pos_sale_line_modifiers')->whereIn('pos_sale_line_id', $lineIds)->delete();
                }
                PosSaleLine::query()->whereIn('pos_sale_id', $saleIds)->delete();
                PosPayment::query()->whereIn('pos_sale_id', $saleIds)->delete();
                PosSale::owned($ownerRef)->delete();
            }

            if (DB::getSchemaBuilder()->hasTable('pos_product_modifier_group')) {
                $productIds = PosProduct::owned($ownerRef)->pluck('id');
                if ($productIds->isNotEmpty()) {
                    DB::table('pos_product_modifier_group')->whereIn('product_id', $productIds)->delete();
                }
            }

            PosProduct::owned($ownerRef)->delete();
            PosDevice::owned($ownerRef)->delete();
            PosMember::owned($ownerRef)->delete();

            if (DB::getSchemaBuilder()->hasTable('pos_tables')) {
                DB::table('pos_tables')->where('owner_ref', $ownerRef)->delete();
            }
            if (DB::getSchemaBuilder()->hasTable('pos_customer_displays')) {
                DB::table('pos_customer_displays')->where('owner_ref', $ownerRef)->delete();
            }
            if (DB::getSchemaBuilder()->hasTable('pos_modifiers')) {
                DB::table('pos_modifiers')->where('owner_ref', $ownerRef)->delete();
            }
            if (DB::getSchemaBuilder()->hasTable('pos_modifier_groups')) {
                DB::table('pos_modifier_groups')->where('owner_ref', $ownerRef)->delete();
            }

            PosCategory::owned($ownerRef)->delete();
            PosStation::owned($ownerRef)->delete();
            PosLocation::owned($ownerRef)->delete();
        });
    }

    /** @return list<PosStation> */
    private function seedStations(string $ownerRef, int $count): array
    {
        if ($count <= 0) {
            return [];
        }

        $stations = PosStation::owned($ownerRef)->orderBy('id')->get()->all();
        $names = ['Hot Kitchen', 'Cold Prep', 'Bar', 'Grill', 'Dessert'];
        for ($i = count($stations); $i < $count; $i++) {
            $stations[] = PosStation::query()->create([
                'owner_ref' => $ownerRef,
                'name' => $names[$i] ?? ('Station '.($i + 1)),
                'position' => $i + 1,
            ]);
        }

        return array_slice($stations, 0, $count);
    }

    /** @return list<PosCategory> */
    private function seedCategories(string $ownerRef): array
    {
        $names = ['Beverages', 'Food', 'Retail', 'Services'];
        $categories = [];
        foreach ($names as $i => $name) {
            $categories[] = PosCategory::query()->firstOrCreate(
                ['owner_ref' => $ownerRef, 'name' => $name],
                ['position' => $i + 1],
            );
        }

        return $categories;
    }

    /** @return list<PosLocation> */
    private function seedLocations(string $ownerRef, int $count): array
    {
        $locations = PosLocation::owned($ownerRef)->orderBy('id')->get()->all();
        $names = ['Main Register', 'Airport Kiosk', 'Mall Counter', 'Campus Store', 'Harbour Outlet'];

        for ($i = count($locations); $i < $count; $i++) {
            $locations[] = PosLocation::query()->create([
                'owner_ref' => $ownerRef,
                'name' => $names[$i] ?? ('Location '.($i + 1)),
                'currency' => 'GHS',
                'is_default' => count($locations) === 0,
                'service_style' => PosLocation::STYLE_RETAIL,
                'receipt_footer' => 'Thank you for shopping with Demo POS.',
            ]);
        }

        if ($locations !== [] && ! collect($locations)->contains(fn (PosLocation $l) => $l->is_default)) {
            $locations[0]->forceFill(['is_default' => true])->save();
        }

        return array_slice($locations, 0, $count);
    }

    private function seedRegister(string $ownerRef, PosLocation $location, bool $primary): void
    {
        $exists = PosDevice::owned($ownerRef)
            ->where('location_id', $location->id)
            ->where('type', 'register')
            ->exists();

        if ($exists) {
            return;
        }

        PosDevice::query()->create([
            'owner_ref' => $ownerRef,
            'location_id' => $location->id,
            'name' => $location->name.' Till',
            'type' => 'register',
            'status' => PosDevice::STATUS_ONLINE,
            'last_online_at' => now(),
            'config' => ['demo' => true, 'primary' => $primary],
        ]);
    }

    /**
     * @param  list<PosCategory>  $categories
     * @param  list<PosStation>  $stations
     * @return list<PosProduct>
     */
    private function seedProducts(
        string $ownerRef,
        PosLocation $location,
        array $categories,
        array $stations,
        int $count,
    ): array {
        $products = PosProduct::owned($ownerRef)
            ->where('location_id', $location->id)
            ->orderBy('id')
            ->get()
            ->all();

        for ($i = count($products); $i < $count; $i++) {
            $name = self::PRODUCT_NAMES[$i % count(self::PRODUCT_NAMES)];
            $products[] = PosProduct::query()->create([
                'owner_ref' => $ownerRef,
                'location_id' => $location->id,
                'category_id' => $categories[$i % count($categories)]->id,
                'station_id' => $stations !== [] ? $stations[$i % count($stations)]->id : null,
                'name' => $name.' '.($i + 1),
                'sku' => 'POS-'.$location->id.'-'.str_pad((string) ($i + 1), 3, '0', STR_PAD_LEFT),
                'price_minor' => 500 + (($i % 20) * 250),
                'currency' => 'GHS',
                'is_active' => true,
            ]);
        }

        return array_slice($products, 0, $count);
    }

    /**
     * @param  list<PosProduct>  $products
     */
    private function seedCashSales(string $ownerRef, PosLocation $location, array $products, int $count): void
    {
        if ($products === []) {
            return;
        }

        $existing = PosSale::owned($ownerRef)->where('location_id', $location->id)->count();
        for ($i = $existing; $i < $count; $i++) {
            $lineCount = 1 + ($i % 3);
            $lines = [];
            $subtotal = 0;
            for ($l = 0; $l < $lineCount; $l++) {
                $product = $products[($i + $l) % count($products)];
                $qty = 1 + ($l % 2);
                $lineTotal = $product->price_minor * $qty;
                $subtotal += $lineTotal;
                $lines[] = [$product, $qty, $lineTotal];
            }

            $sale = PosSale::query()->create([
                'owner_ref' => $ownerRef,
                'location_id' => $location->id,
                'reference' => 'DEMO-'.$location->id.'-'.str_pad((string) ($i + 1), 4, '0', STR_PAD_LEFT).'-'.substr(md5($ownerRef.$i), 0, 6),
                'status' => PosSale::STATUS_PAID,
                'payment_method' => PosSale::METHOD_CASH,
                'order_type' => PosSale::ORDER_COUNTER,
                'kitchen_status' => PosSale::KITCHEN_NONE,
                'customer_name' => 'Cash Customer '.($i + 1),
                'subtotal_minor' => $subtotal,
                'total_minor' => $subtotal,
                'currency' => 'GHS',
                'paid_at' => now()->subDays($i % 10)->subMinutes($i * 3),
                'opened_at' => now()->subDays($i % 10)->subMinutes(($i * 3) + 5),
                'closed_at' => now()->subDays($i % 10)->subMinutes($i * 3),
            ]);

            foreach ($lines as $pos => [$product, $qty, $lineTotal]) {
                PosSaleLine::query()->create([
                    'pos_sale_id' => $sale->id,
                    'product_id' => $product->id,
                    'station_id' => $product->station_id,
                    'name' => $product->name,
                    'unit_price_minor' => $product->price_minor,
                    'quantity' => $qty,
                    'line_total_minor' => $lineTotal,
                    'position' => $pos,
                ]);
            }

            PosPayment::query()->create([
                'pos_sale_id' => $sale->id,
                'owner_ref' => $ownerRef,
                'amount_minor' => $subtotal,
                'method' => PosPayment::METHOD_CASH,
                'status' => PosPayment::STATUS_PAID,
                'paid_at' => $sale->paid_at,
            ]);
        }
    }

    private function seedTeam(User $owner): void
    {
        if (PosMember::owned($owner->public_id)->exists()) {
            return;
        }

        $cashier = User::query()->firstOrCreate(
            ['email' => 'demo-cashier-'.$owner->id.'@ladill.local'],
            [
                'public_id' => (string) Str::uuid(),
                'name' => 'Demo Cashier',
                'password' => bcrypt('password'),
                'email_verified_at' => now(),
            ],
        );

        $location = PosLocation::owned($owner->public_id)->orderBy('id')->first();

        PosMember::query()->create([
            'owner_ref' => $owner->public_id,
            'user_ref' => $cashier->public_id,
            'role' => PosMember::ROLE_CASHIER,
            'location_id' => $location?->id,
        ]);
    }

    private function normalizePlan(string $plan): string
    {
        $plan = strtolower(trim($plan));
        if (! in_array($plan, ['free', 'pro', 'enterprise'], true)) {
            throw new \InvalidArgumentException('Plan must be free, pro, or enterprise.');
        }

        return $plan;
    }
}