<?php

namespace App\Services\Qr;

use App\Models\QrCode;
use App\Support\Qr\QrDateFormatter;
use App\Support\Qr\QrTypeCatalog;
use Illuminate\Http\UploadedFile;
use RuntimeException;

class QrPayloadValidator
{
    /**
     * @param  array<string, mixed>  $input
     * @return array{content: array<string, mixed>, destination_url: ?string}
     */
    public function validateForCreate(string $type, array $input): array
    {
        if (! QrTypeCatalog::isValid($type)) {
            throw new RuntimeException('Invalid QR type selected.');
        }

        return match ($type) {
            QrCode::TYPE_URL => $this->validateUrl($input),
            QrCode::TYPE_DOCUMENT => $this->validateDocument($input),
            QrCode::TYPE_LINK_LIST => $this->validateLinkList($input),
            QrCode::TYPE_VCARD => $this->validateVcard($input),
            QrCode::TYPE_BUSINESS => $this->validateBusiness($input),
            QrCode::TYPE_CHURCH => $this->validateChurch($input),
            QrCode::TYPE_EVENT => $this->validateEvent($input),
            QrCode::TYPE_ITINERARY => $this->validateItinerary($input),
            QrCode::TYPE_IMAGE => ['content' => [], 'destination_url' => null],
            QrCode::TYPE_MENU => $this->validateMenu($input),
            QrCode::TYPE_SHOP => $this->validateShop($input),
            QrCode::TYPE_APP => $this->validateApp($input),
            QrCode::TYPE_BOOK => $this->validateBook($input),
            QrCode::TYPE_WIFI => $this->validateWifi($input),
            QrCode::TYPE_PAYMENT => $this->validatePayment($input),
            default => throw new RuntimeException('Unsupported QR type.'),
        };
    }

    /**
     * @param  array<string, mixed>  $input
     * @return array{content: array<string, mixed>, destination_url: ?string}
     */
    public function validateForUpdate(QrCode $qrCode, array $input): array
    {
        $merged = array_merge($qrCode->content(), $input);

        if ($qrCode->isUrlType() && empty($merged['destination_url']) && ! empty($merged['url'])) {
            $merged['destination_url'] = $merged['url'];
        }

        return $this->validateForCreate($qrCode->type, $merged);
    }

    /** @param  array<string, mixed>  $input */
    private function validateDocument(array $input): array
    {
        $allowDownload = filter_var($input['allow_download'] ?? true, FILTER_VALIDATE_BOOL);

        return ['content' => ['allow_download' => $allowDownload], 'destination_url' => null];
    }

    /** @param  array<string, mixed>  $input */
    private function validateUrl(array $input): array
    {
        $url = $this->requireUrl($input['destination_url'] ?? null, 'Enter a valid destination URL.');

        return ['content' => ['url' => $url], 'destination_url' => $url];
    }

    /** @param  array<string, mixed>  $input */
    private function validateLinkList(array $input): array
    {
        $links = $this->normalizeLinks($input['links'] ?? []);

        if ($links === []) {
            throw new RuntimeException('Add at least one link.');
        }

        return ['content' => ['links' => $links], 'destination_url' => null];
    }

    /** @param  array<string, mixed>  $input */
    private function validateVcard(array $input): array
    {
        $first = trim((string) ($input['first_name'] ?? ''));
        $last  = trim((string) ($input['last_name'] ?? ''));

        if ($first === '' && $last === '') {
            throw new RuntimeException('Enter a first or last name for the vCard.');
        }

        $social = [];
        foreach (['linkedin', 'twitter', 'instagram', 'facebook', 'tiktok', 'youtube', 'whatsapp', 'snapchat'] as $platform) {
            $raw = trim((string) (($input['social'] ?? [])[$platform] ?? ''));
            if ($raw !== '') {
                $social[$platform] = static::normalizeSocialUrl($platform, $raw);
            }
        }

        return [
            'content' => [
                'first_name'  => $first,
                'last_name'   => $last,
                'phone'       => trim((string) ($input['phone'] ?? '')),
                'email'       => trim((string) ($input['email'] ?? '')),
                'company'     => trim((string) ($input['company'] ?? '')),
                'website'     => trim((string) ($input['website'] ?? '')),
                'address'     => trim((string) ($input['address'] ?? '')),
                'note'        => trim((string) ($input['note'] ?? '')),
                'avatar_path' => $input['avatar_path'] ?? null,
                'social'      => $social,
            ],
            'destination_url' => null,
        ];
    }

    /** @param  array<string, mixed>  $input */
    private function validateBusiness(array $input): array
    {
        $name = trim((string) ($input['name'] ?? ''));

        if ($name === '') {
            throw new RuntimeException('Enter a business name.');
        }

        $social = [];
        foreach (['linkedin', 'twitter', 'instagram', 'facebook', 'tiktok', 'youtube', 'whatsapp', 'snapchat'] as $platform) {
            $raw = trim((string) (($input['social'] ?? [])[$platform] ?? ''));
            if ($raw !== '') {
                $social[$platform] = static::normalizeSocialUrl($platform, $raw);
            }
        }

        return [
            'content' => [
                'name'        => $name,
                'tagline'     => trim((string) ($input['tagline'] ?? '')),
                'phone'       => trim((string) ($input['phone'] ?? '')),
                'email'       => trim((string) ($input['email'] ?? '')),
                'website'     => trim((string) ($input['website'] ?? '')),
                'address'     => trim((string) ($input['address'] ?? '')),
                'hours'       => trim((string) ($input['hours'] ?? '')),
                'brand_color' => $this->normalizeBrandColor($input['brand_color'] ?? null),
                'logo_path'   => $input['logo_path'] ?? null,
                'cover_path'  => $input['cover_path'] ?? null,
                'social'      => $social,
            ],
            'destination_url' => null,
        ];
    }

    /** @param  array<string, mixed>  $input */
    private function validateChurch(array $input): array
    {
        $name = trim((string) ($input['name'] ?? ''));
        if ($name === '') {
            throw new RuntimeException('Enter the church name.');
        }

        $orgTypes = ['church', 'school', 'mosque', 'ngo', 'club'];
        $orgType  = in_array($input['org_type'] ?? 'church', $orgTypes) ? $input['org_type'] : 'church';

        // Normalise legacy lowercase slugs → display strings
        $legacyMap       = ['offering' => 'Offering', 'tithe' => 'Tithe', 'donation' => 'Donation', 'harvest' => 'Harvest'];
        $collectionTypes = array_values(array_unique(array_filter(
            array_map(fn ($t) => $legacyMap[strtolower(trim((string) $t))] ?? ucwords(trim((string) $t)), (array) ($input['collection_types'] ?? [])),
            fn ($t) => $t !== '' && strlen($t) <= 60
        )));
        if (empty($collectionTypes)) {
            $collectionTypes = ['Offering', 'Tithe', 'Donation', 'Harvest'];
        }

        return [
            'content' => [
                'name'             => $name,
                'denomination'     => trim((string) ($input['denomination'] ?? '')),
                'description'      => trim((string) ($input['description'] ?? '')),
                'phone'            => trim((string) ($input['phone'] ?? '')),
                'email'            => trim((string) ($input['email'] ?? '')),
                'website'          => trim((string) ($input['website'] ?? '')),
                'address'          => trim((string) ($input['address'] ?? '')),
                'service_times'    => trim((string) ($input['service_times'] ?? '')),
                'brand_color'      => $this->normalizeBrandColor($input['brand_color'] ?? null) ?? '#1a3a5c',
                'logo_path'        => $input['logo_path'] ?? null,
                'cover_path'       => $input['cover_path'] ?? null,
                'org_type'         => $orgType,
                'accepts_payment'  => filter_var($input['accepts_payment'] ?? false, FILTER_VALIDATE_BOOL),
                'currency'         => 'GHS',
                'collection_types' => $collectionTypes,
            ],
            'destination_url' => null,
        ];
    }

    /** @param  array<string, mixed>  $input */
    private function validateEvent(array $input): array
    {
        $name = trim((string) ($input['name'] ?? ''));
        if ($name === '') {
            throw new RuntimeException('Enter the event name.');
        }

        // Ticket tiers: [{ name, price, capacity }]
        $tiers = [];
        foreach ((array) ($input['tiers'] ?? []) as $tier) {
            if (! is_array($tier)) {
                continue;
            }
            $tierName = trim((string) ($tier['name'] ?? ''));
            if ($tierName === '') {
                continue;
            }
            $price = round((float) ($tier['price'] ?? 0), 2);
            $capacity = (int) ($tier['capacity'] ?? 0);
            $tiers[] = [
                'name'     => mb_substr($tierName, 0, 80),
                'price'    => max(0, $price),
                'capacity' => max(0, $capacity), // 0 = unlimited
            ];
        }
        if (empty($tiers)) {
            $tiers = [['name' => 'General Admission', 'price' => 0.0, 'capacity' => 0]];
        }

        // Extra registration/badge fields the organiser wants captured.
        $badgeFields = [];
        foreach ((array) ($input['badge_fields'] ?? []) as $field) {
            $label = trim((string) (is_array($field) ? ($field['label'] ?? '') : $field));
            if ($label !== '' && strlen($label) <= 60) {
                $badgeFields[] = mb_substr($label, 0, 60);
            }
        }

        // Mode: sell tickets, collect cash contributions (weddings, non-profits),
        // or a free event (registration only — no tickets, no contributions).
        $mode = in_array($input['mode'] ?? 'ticketing', ['ticketing', 'contributions', 'free'], true)
            ? ($input['mode'] ?? 'ticketing')
            : 'ticketing';

        // Contribution categories: ['Wedding Gift', 'Donation', …]
        $categories = [];
        foreach ((array) ($input['contribution_categories'] ?? []) as $cat) {
            $label = trim((string) (is_array($cat) ? ($cat['name'] ?? '') : $cat));
            if ($label !== '') {
                $categories[] = mb_substr($label, 0, 80);
            }
        }
        if ($mode === 'contributions' && empty($categories)) {
            $categories = ['Contribution'];
        }

        // Free events collect neither tickets nor contributions — a single free
        // registration. Forced deterministically so switching from a paid setup
        // can never leave a chargeable tier behind.
        if ($mode === 'free') {
            $tiers = [['name' => 'Registration', 'price' => 0.0, 'capacity' => 0]];
            $categories = [];
        }

        // Contributions always take payment; ticketing only for paid tiers; free never.
        $acceptsPayment = match ($mode) {
            'contributions' => true,
            'free' => false,
            default => $this->eventHasPaidTier($tiers),
        };

        return [
            'content' => [
                'name'            => mb_substr($name, 0, 120),
                'tagline'         => trim((string) ($input['tagline'] ?? '')),
                'description'     => trim((string) ($input['description'] ?? '')),
                'location'        => trim((string) ($input['location'] ?? '')),
                'starts_at'       => QrDateFormatter::normalize((string) ($input['starts_at'] ?? '')),
                'ends_at'         => QrDateFormatter::normalize((string) ($input['ends_at'] ?? '')),
                'organizer'       => trim((string) ($input['organizer'] ?? '')),
                'website'         => trim((string) ($input['website'] ?? '')),
                'brand_color'     => $this->normalizeBrandColor($input['brand_color'] ?? null) ?? '#4f46e5',
                'logo_path'       => $input['logo_path'] ?? null,
                'cover_path'      => $input['cover_path'] ?? null,
                'currency'        => 'GHS',
                'mode'            => $mode,
                'tiers'           => array_values($tiers),
                'contribution_categories' => array_values($categories),
                'badge_fields'    => array_values($badgeFields),
                'badge_size'      => in_array($input['badge_size'] ?? '4x3', ['4x3', '4x6', 'cr80'], true) ? ($input['badge_size'] ?? '4x3') : '4x3',
                'accepts_payment' => $acceptsPayment,
                'registration_open' => filter_var($input['registration_open'] ?? true, FILTER_VALIDATE_BOOL),
                'programme_qr_id' => ($pid = (int) ($input['programme_qr_id'] ?? 0)) > 0 ? $pid : null,
            ],
            'destination_url' => null,
        ];
    }

    /** @param  array<int, array{price: float}>  $tiers */
    private function eventHasPaidTier(array $tiers): bool
    {
        foreach ($tiers as $tier) {
            if ((float) ($tier['price'] ?? 0) > 0) {
                return true;
            }
        }

        return false;
    }

    /** @param  array<string, mixed>  $input */
    private function validateItinerary(array $input): array
    {
        $title = trim((string) ($input['title'] ?? ''));
        if ($title === '') {
            throw new RuntimeException('Enter the itinerary title.');
        }

        // Days: [{ label, date, items: [{ time, title, description, location, host }] }]
        $days = [];
        foreach ((array) ($input['days'] ?? []) as $day) {
            if (! is_array($day)) {
                continue;
            }
            $items = [];
            foreach ((array) ($day['items'] ?? []) as $item) {
                if (! is_array($item)) {
                    continue;
                }
                $itemTitle = trim((string) ($item['title'] ?? ''));
                if ($itemTitle === '') {
                    continue;
                }
                $items[] = [
                    'time'        => mb_substr(trim((string) ($item['time'] ?? '')), 0, 40),
                    'title'       => mb_substr($itemTitle, 0, 140),
                    'description' => mb_substr(trim((string) ($item['description'] ?? '')), 0, 400),
                    'location'    => mb_substr(trim((string) ($item['location'] ?? '')), 0, 120),
                    'host'        => mb_substr(trim((string) ($item['host'] ?? '')), 0, 120),
                ];
            }
            if (empty($items) && trim((string) ($day['label'] ?? '')) === '') {
                continue;
            }
            $days[] = [
                'label' => mb_substr(trim((string) ($day['label'] ?? '')), 0, 80),
                'date'  => QrDateFormatter::normalize((string) ($day['date'] ?? '')),
                'items' => array_values($items),
            ];
        }
        if (empty($days)) {
            throw new RuntimeException('Add at least one programme item.');
        }

        return [
            'content' => [
                'title'       => mb_substr($title, 0, 120),
                'subtitle'    => trim((string) ($input['subtitle'] ?? '')),
                'description' => trim((string) ($input['description'] ?? '')),
                'event_date'  => QrDateFormatter::normalize((string) ($input['event_date'] ?? '')),
                'location'    => trim((string) ($input['location'] ?? '')),
                'brand_color' => $this->normalizeBrandColor($input['brand_color'] ?? null) ?? '#b45309',
                'cover_path'  => $input['cover_path'] ?? null,
                'days'        => array_values($days),
            ],
            'destination_url' => null,
        ];
    }

    /** @param  array<string, mixed>  $input */
    private function validateMenu(array $input): array
    {
        $title = trim((string) ($input['menu_title'] ?? 'Menu'));
        $sections = $this->normalizeMenuSections($input['sections'] ?? []);
        $acceptsPayment = filter_var($input['accepts_payment'] ?? false, FILTER_VALIDATE_BOOL);

        $shippingType = in_array($input['shipping_type'] ?? 'none', ['none', 'flat'], true)
            ? (string) ($input['shipping_type'] ?? 'none')
            : 'none';
        $shippingFee = $shippingType === 'flat' ? round(max(0, (float) ($input['shipping_fee'] ?? 0)), 2) : 0.0;
        $freeShippingAbove = round(max(0, (float) ($input['free_shipping_above'] ?? 0)), 2);

        if ($sections === []) {
            throw new RuntimeException('Add at least one menu section with items.');
        }

        return [
            'content' => [
                'title' => $title,
                'sections' => $sections,
                'accepts_payment' => $acceptsPayment,
                'shipping_type' => $shippingType,
                'shipping_fee' => $shippingFee,
                'free_shipping_above' => $freeShippingAbove,
                'brand_color' => $this->normalizeBrandColor($input['brand_color'] ?? null),
                'logo_path' => $input['logo_path'] ?? null,
                'cover_path' => $input['cover_path'] ?? null,
            ],
            'destination_url' => null,
        ];
    }

    /** @param  array<string, mixed>  $input */
    private function validateShop(array $input): array
    {
        $title = trim((string) ($input['shop_title'] ?? $input['menu_title'] ?? 'Shop'));
        $currency = trim((string) ($input['currency'] ?? 'GHS'));
        $sections = $this->normalizeMenuSections($input['sections'] ?? []);
        $acceptsPayment = filter_var($input['accepts_payment'] ?? false, FILTER_VALIDATE_BOOL);

        $shippingType = in_array($input['shipping_type'] ?? 'none', ['none', 'flat'], true)
            ? (string) ($input['shipping_type'] ?? 'none')
            : 'none';
        $shippingFee = $shippingType === 'flat' ? round(max(0, (float) ($input['shipping_fee'] ?? 0)), 2) : 0.0;
        $freeShippingAbove = round(max(0, (float) ($input['free_shipping_above'] ?? 0)), 2);

        if ($sections === []) {
            throw new RuntimeException('Add at least one category with products.');
        }

        return [
            'content' => [
                'title' => $title,
                'currency' => $currency,
                'sections' => $sections,
                'accepts_payment' => $acceptsPayment,
                'shipping_type' => $shippingType,
                'shipping_fee' => $shippingFee,
                'free_shipping_above' => $freeShippingAbove,
                'brand_color' => $this->normalizeBrandColor($input['brand_color'] ?? null),
                'logo_path' => $input['logo_path'] ?? null,
                'cover_path' => $input['cover_path'] ?? null,
            ],
            'destination_url' => null,
        ];
    }

    private function normalizeBrandColor(mixed $value): ?string
    {
        if ($value === null) {
            return null;
        }
        $hex = trim((string) $value);

        return preg_match('/^#[0-9A-Fa-f]{6}$/', $hex) ? $hex : null;
    }

    /** @param  array<string, mixed>  $input */
    private function validateApp(array $input): array
    {
        $name = trim((string) ($input['app_name'] ?? ''));
        $ios = trim((string) ($input['ios_url'] ?? ''));
        $android = trim((string) ($input['android_url'] ?? ''));
        $web = trim((string) ($input['web_url'] ?? ''));

        if ($name === '') {
            throw new RuntimeException('Enter an app name.');
        }

        if ($ios === '' && $android === '' && $web === '') {
            throw new RuntimeException('Add at least one app store or website link.');
        }

        foreach (['ios' => $ios, 'android' => $android, 'web' => $web] as $label => $url) {
            if ($url !== '' && ! filter_var($url, FILTER_VALIDATE_URL)) {
                throw new RuntimeException("Enter a valid {$label} URL.");
            }
        }

        return [
            'content' => [
                'name' => $name,
                'ios_url' => $ios,
                'android_url' => $android,
                'web_url' => $web,
                'icon_path' => $input['icon_path'] ?? null,
            ],
            'destination_url' => $web ?: ($ios ?: $android),
        ];
    }

    /** @param  array<string, mixed>  $input */
    private function validateBook(array $input): array
    {
        $title  = trim((string) ($input['book_title'] ?? ''));
        $author = trim((string) ($input['author'] ?? ''));
        $price  = (float) ($input['price_ghs'] ?? 0);

        if ($title === '') {
            throw new RuntimeException('Enter the book title.');
        }
        if ($author === '') {
            throw new RuntimeException('Enter the author name.');
        }
        if ($price <= 0) {
            throw new RuntimeException('Enter a price greater than zero.');
        }

        return [
            'content' => [
                'book_title'  => $title,
                'author'      => $author,
                'description' => trim((string) ($input['description'] ?? '')),
                'price_ghs'   => round($price, 2),
                'cover_path'  => $input['cover_path'] ?? null,
                'file_path'   => $input['file_path'] ?? null,
                'file_type'   => $input['file_type'] ?? null,
                'file_size'   => (int) ($input['file_size'] ?? 0),
            ],
            'destination_url' => null,
        ];
    }

    /** @param  array<string, mixed>  $input */
    private function validateWifi(array $input): array
    {
        $ssid = trim((string) ($input['ssid'] ?? ''));
        if ($ssid === '') {
            throw new RuntimeException('Enter a WiFi network name (SSID).');
        }

        $encryption = strtoupper(trim((string) ($input['encryption'] ?? 'WPA')));
        if (! in_array($encryption, ['WPA', 'WEP', 'NOPASS'], true)) {
            $encryption = 'WPA';
        }

        return [
            'content' => [
                'ssid' => $ssid,
                'password' => (string) ($input['password'] ?? ''),
                'encryption' => $encryption,
                'hidden' => filter_var($input['hidden'] ?? false, FILTER_VALIDATE_BOOL),
            ],
            'destination_url' => null,
        ];
    }

    public static function normalizeSocialUrl(string $platform, string $value): string
    {
        // Already a full URL — leave as-is
        if (str_starts_with($value, 'http://') || str_starts_with($value, 'https://')) {
            return $value;
        }

        $handle = ltrim($value, '@');

        return match ($platform) {
            'linkedin'  => 'https://linkedin.com/in/' . $handle,
            'twitter'   => 'https://x.com/' . $handle,
            'instagram' => 'https://instagram.com/' . $handle,
            'facebook'  => 'https://facebook.com/' . $handle,
            'tiktok'    => 'https://tiktok.com/@' . $handle,
            'youtube'   => 'https://youtube.com/@' . $handle,
            'snapchat'  => 'https://snapchat.com/add/' . $handle,
            'whatsapp'  => 'https://wa.me/' . preg_replace('/\D+/', '', $value),
            default     => $value,
        };
    }

    private function requireUrl(mixed $value, string $message): string
    {
        $url = trim((string) $value);
        if ($url === '' || ! filter_var($url, FILTER_VALIDATE_URL)) {
            throw new RuntimeException($message);
        }

        return $url;
    }

    /** @return list<array{title: string, url: string}> */
    private function normalizeLinks(mixed $links): array
    {
        if (! is_array($links)) {
            return [];
        }

        $normalized = [];
        foreach ($links as $link) {
            if (! is_array($link)) {
                continue;
            }
            $title = trim((string) ($link['title'] ?? ''));
            $url = trim((string) ($link['url'] ?? ''));
            if ($title === '' || $url === '' || ! filter_var($url, FILTER_VALIDATE_URL)) {
                continue;
            }
            $normalized[] = ['title' => $title, 'url' => $url];
        }

        return $normalized;
    }

    /**
     * Normalize menu/shop sections. Preserves existing image_path on items so that
     * the manager can inject freshly uploaded paths after validation.
     *
     * @return list<array{name: string, items: list<array{name: string, description: string, price: string, image_path: ?string}>}>
     */
    private function normalizeMenuSections(mixed $sections): array
    {
        if (! is_array($sections)) {
            return [];
        }

        $normalized = [];
        foreach ($sections as $section) {
            if (! is_array($section)) {
                continue;
            }
            $name = trim((string) ($section['name'] ?? ''));
            $items = [];
            foreach (($section['items'] ?? []) as $item) {
                if (! is_array($item)) {
                    continue;
                }
                $itemName = trim((string) ($item['name'] ?? ''));
                if ($itemName === '') {
                    continue;
                }
                $items[] = [
                    'name' => $itemName,
                    'description' => trim((string) ($item['description'] ?? '')),
                    'price' => trim((string) ($item['price'] ?? '')),
                    'image_path' => ($item['image_path'] ?? null) ?: null,
                ];
            }
            if ($name !== '' && $items !== []) {
                $normalized[] = ['name' => $name, 'items' => $items];
            }
        }

        return $normalized;
    }

    public function validateImageUpload(?UploadedFile $file): void
    {
        if (! $file instanceof UploadedFile) {
            throw new RuntimeException('Upload at least one image.');
        }

        $mime = $file->getMimeType() ?: '';
        if (! str_starts_with($mime, 'image/')) {
            throw new RuntimeException('Only image files are supported.');
        }
    }

    /** @param  array<string, mixed>  $input */
    private function validatePayment(array $input): array
    {
        $businessName = trim((string) ($input['business_name'] ?? ''));
        if ($businessName === '') {
            throw new RuntimeException('Enter your business or display name.');
        }

        return [
            'content' => [
                'business_name' => mb_substr($businessName, 0, 120),
                'branch_label' => mb_substr(trim((string) ($input['branch_label'] ?? '')), 0, 80) ?: null,
                'currency' => strtoupper(trim((string) ($input['currency'] ?? 'GHS'))) ?: 'GHS',
            ],
            'destination_url' => null,
        ];
    }
}