<?php

namespace App\Services\Hosting;

use App\Jobs\DeactivateMailboxJob;
use App\Jobs\ProvisionMailboxJob;
use App\Services\Mail\MailboxUserProvisioner;
use App\Models\Domain;
use App\Models\HostingAccount;
use App\Models\HostingBillingInvoice;
use App\Models\Mailbox;
use Illuminate\Support\Facades\Hash;
use Illuminate\Support\Str;
use Illuminate\Validation\ValidationException;

class HostingMailboxService
{
    public const EXTRA_MAILBOX_PRICE_CEDIS = 5;

    public function __construct(
        protected MailboxUserProvisioner $mailboxUsers,
    ) {}

    /**
     * @return array<string, mixed>
     */
    public function usageSummary(HostingAccount $account): array
    {
        $account->loadMissing(['product']);

        $mailboxes = $account->loadedMailboxes();
        $freeAllowance = $account->freeEmailAllowance();
        $mailboxCount = $mailboxes->count();
        $paidCount = $mailboxes->where('is_paid', true)->count();
        $freeUsed = $freeAllowance === null ? $mailboxCount : min($mailboxCount, $freeAllowance);
        $extraCount = max($mailboxCount - ($freeAllowance ?? $mailboxCount), 0);

        return [
            'mailbox_count' => $mailboxCount,
            'free_allowance' => $freeAllowance,
            'free_used' => $freeUsed,
            'paid_count' => $paidCount,
            'extra_count' => $extraCount,
            'extra_price' => self::EXTRA_MAILBOX_PRICE_CEDIS,
            'extra_total' => round($extraCount * self::EXTRA_MAILBOX_PRICE_CEDIS, 2),
            'breakdown' => sprintf(
                'Extra Emails: %d x GHS %d = GHS %.2f',
                $extraCount,
                self::EXTRA_MAILBOX_PRICE_CEDIS,
                round($extraCount * self::EXTRA_MAILBOX_PRICE_CEDIS, 2)
            ),
        ];
    }

    public function createMailbox(HostingAccount $account, array $input): array
    {
        $account->loadMissing(['product', 'sites']);

        if (! HostingAccount::tracksLocalMailboxes()) {
            throw ValidationException::withMessages([
                'local_part' => 'Mailbox creation is managed in Ladill Email.',
            ]);
        }

        $account->loadMissing(['mailboxes']);

        $domain = Domain::query()
            ->whereKey((int) ($input['domain_id'] ?? 0))
            ->where('hosting_account_id', $account->id)
            ->first();

        if (! $domain) {
            throw ValidationException::withMessages([
                'domain_id' => 'Select a domain linked to this hosting account.',
            ]);
        }

        $localPart = strtolower(trim((string) ($input['local_part'] ?? '')));
        $address = "{$localPart}@{$domain->host}";

        if (Mailbox::query()->where('address', $address)->exists()) {
            throw ValidationException::withMessages([
                'local_part' => 'This mailbox address already exists.',
            ]);
        }

        $summary = $this->usageSummary($account);
        $freeAllowance = $summary['free_allowance'];
        $isPaid = $freeAllowance !== null && $summary['mailbox_count'] >= $freeAllowance;

        $mailbox = Mailbox::query()->create([
            'user_id' => $account->user_id,
            'website_id' => null,
            'hosting_account_id' => $account->id,
            'domain_id' => $domain->id,
            'display_name' => (string) ($input['display_name'] ?? $localPart),
            'local_part' => $localPart,
            'address' => $address,
            'password_hash' => Hash::make((string) $input['password']),
            'quota_mb' => (int) ($input['quota_mb'] ?? Mailbox::defaultQuotaMb()),
            'status' => 'provisioning',
            'is_paid' => $isPaid,
            'paid_at' => $isPaid ? now() : null,
            'billing_type' => $isPaid ? 'subscription' : 'free',
            'monthly_price' => $isPaid ? self::EXTRA_MAILBOX_PRICE_CEDIS : null,
            'subscription_started_at' => $isPaid ? now() : null,
            'subscription_expires_at' => $isPaid ? now()->addMonth() : null,
            'subscription_status' => 'active',
            'maildir_path' => sprintf('hosting/%d/%s/%s', $account->id, $domain->host, $localPart),
            'credentials_issued_at' => now(),
            'incoming_token' => Str::random(64),
            'inbound_enabled' => true,
            'outbound_enabled' => true,
            'outbound_provider' => 'smtp',
            'metadata' => [
                'provisioned_by' => 'hosting_account',
                'hosting_account_id' => $account->id,
            ],
        ]);

        $this->mailboxUsers->provisionMailboxSilently($mailbox, (string) $input['password']);

        ProvisionMailboxJob::dispatch($mailbox->id, encrypt((string) $input['password']));

        $invoice = $this->syncAddonInvoice($account->fresh());

        return [
            'mailbox' => $mailbox->fresh(['domain']),
            'usage' => $this->usageSummary($account->fresh(['product'])),
            'invoice' => $invoice,
        ];
    }

    public function deleteMailbox(HostingAccount $account, Mailbox $mailbox): ?HostingBillingInvoice
    {
        if ((int) $mailbox->hosting_account_id !== (int) $account->id) {
            throw ValidationException::withMessages([
                'mailbox_id' => 'Mailbox does not belong to this hosting account.',
            ]);
        }

        $mailbox->update(['status' => 'deleting']);
        DeactivateMailboxJob::dispatch($mailbox->id);

        return $this->syncAddonInvoice($account->fresh());
    }

    public function syncAddonInvoice(HostingAccount $account): ?HostingBillingInvoice
    {
        $account->loadMissing(['product']);
        $summary = $this->usageSummary($account);
        if ($summary['extra_count'] === 0) {
            HostingBillingInvoice::query()
                ->where('hosting_account_id', $account->id)
                ->where('invoice_type', HostingBillingInvoice::TYPE_EMAIL_ADDON)
                ->where('status', HostingBillingInvoice::STATUS_PENDING)
                ->delete();

            return null;
        }

        return HostingBillingInvoice::query()->updateOrCreate(
            [
                'hosting_account_id' => $account->id,
                'invoice_type' => HostingBillingInvoice::TYPE_EMAIL_ADDON,
                'status' => HostingBillingInvoice::STATUS_PENDING,
            ],
            [
                'user_id' => $account->user_id,
                'currency' => 'GHS',
                'subtotal_amount' => $summary['extra_total'],
                'credit_amount' => 0,
                'total_amount' => $summary['extra_total'],
                'description' => sprintf('Extra mailbox charges for %s', $account->primary_domain ?: $account->username),
                'line_items' => [[
                    'code' => 'extra_emails',
                    'label' => 'Extra Emails',
                    'quantity' => $summary['extra_count'],
                    'unit_amount' => self::EXTRA_MAILBOX_PRICE_CEDIS,
                    'amount' => $summary['extra_total'],
                    'description' => $summary['breakdown'],
                ]],
                'metadata' => [
                    'billing_period' => now()->format('Y-m'),
                    'extra_mailboxes' => $summary['extra_count'],
                ],
            ]
        );
    }
}