<?php
declare(strict_types=1);

namespace Esun\Reward\Model;

use Magento\Framework\App\Config\ScopeConfigInterface;
use Magento\Framework\Serialize\Serializer\Json;
use Magento\Store\Model\ScopeInterface;

class Config
{
    public function __construct(
        private readonly ScopeConfigInterface $scopeConfig,
        private readonly Json $serializer
    ) {}

    public function isEnabled(?int $storeId = null): bool { return $this->flag('general/enabled', $storeId); }
    public function registrationPoints(?int $storeId = null): int { return (int)$this->earningRule('registration', $storeId)['points']; }
    public function firstAddressPoints(?int $storeId = null): int { return (int)$this->earningRule('first_shipping_address', $storeId)['points']; }
    public function orderRate(?int $storeId = null): float { return (float)$this->earningRule('order_earned', $storeId)['points']; }
    public function reviewTextPoints(?int $storeId = null): int { return (int)$this->earningRule('review_text', $storeId)['points']; }
    public function reviewMediaPoints(?int $storeId = null): int { return (int)$this->earningRule('review_media', $storeId)['points']; }
    public function socialPoints(?int $storeId = null): int { return (int)$this->earningRule('social_share', $storeId)['points']; }
    public function redemptionRate(?int $storeId = null): int { return max(1, $this->int('spending/points_per_dollar', $storeId)); }
    public function maxCheckoutPoints(?int $storeId = null): int { return $this->int('spending/max_checkout_points', $storeId); }
    public function reviewEligibility(?int $storeId = null): string { return (string)$this->value('review/eligibility', $storeId); }
    public function silverThreshold(?int $storeId = null): float { return $this->float('tiers/silver_threshold', $storeId); }
    public function silverMultiplier(?int $storeId = null): float { return $this->float('tiers/silver_multiplier', $storeId); }
    public function goldThreshold(?int $storeId = null): float { return $this->float('tiers/gold_threshold', $storeId); }
    public function goldMultiplier(?int $storeId = null): float { return $this->float('tiers/gold_multiplier', $storeId); }

    /** @return array{code: string, points: float, name: string, reason: string} */
    public function earningRule(string $code, ?int $storeId = null): array
    {
        $rules = $this->earningRules($storeId);
        return $rules[$code] ?? ['code' => $code, 'points' => 0.0, 'name' => ucwords(str_replace('_', ' ', $code)), 'reason' => ''];
    }

    /** @return array<string, array{code: string, points: float, name: string, reason: string}> */
    public function earningRules(?int $storeId = null): array
    {
        $defaults = [
            'registration' => ['points' => (float)$this->int('earning/registration_points', $storeId), 'name' => 'Account Registration', 'reason' => 'Account registration reward'],
            'first_shipping_address' => ['points' => (float)$this->int('earning/first_address_points', $storeId), 'name' => 'First Shipping Address', 'reason' => 'First saved shipping address reward'],
            'order_earned' => ['points' => $this->float('earning/points_per_dollar', $storeId), 'name' => 'Order Reward', 'reason' => 'Points earned from order %1'],
            'review_text' => ['points' => (float)$this->int('earning/review_text_points', $storeId), 'name' => 'Product Review', 'reason' => 'Approved product review reward'],
            'review_media' => ['points' => (float)$this->int('earning/review_media_points', $storeId), 'name' => 'Product Review with Media', 'reason' => 'Approved product review reward'],
            'social_share' => ['points' => (float)$this->int('earning/social_share_points', $storeId), 'name' => 'Social Share', 'reason' => 'Social share reward'],
        ];
        foreach ($defaults as $code => &$rule) {
            $rule['code'] = $code;
        }
        unset($rule);

        $value = $this->value('earning/items', $storeId);
        try {
            $items = is_array($value) ? $value : (empty($value) ? [] : $this->serializer->unserialize((string)$value));
        } catch (\InvalidArgumentException) {
            $items = [];
        }
        if (!is_array($items) || !$items) {
            return $defaults;
        }

        $rules = [];
        foreach ($items as $item) {
            if (!is_array($item)) {
                continue;
            }
            $code = strtolower(trim((string)($item['code'] ?? '')));
            $name = trim((string)($item['name'] ?? ''));
            if ($code === '' || $name === '') {
                continue;
            }
            $rules[$code] = [
                'code' => $code,
                'points' => max(0.0, (float)($item['points'] ?? 0)),
                'name' => $name,
                'reason' => trim((string)($item['reason'] ?? '')),
            ];
        }
        return $rules ?: $defaults;
    }

    /** @return array<int, array{code: string, label: string, threshold: float, multiplier: float}> */
    public function tiers(?int $storeId = null): array
    {
        $value = $this->value('tiers/items', $storeId);
        try {
            $items = is_array($value) ? $value : (empty($value) ? [] : $this->serializer->unserialize((string)$value));
        } catch (\InvalidArgumentException) {
            $items = [];
        }
        if (!is_array($items)) {
            $items = [];
        }

        $tiers = [];
        foreach ($items as $item) {
            if (!is_array($item)) {
                continue;
            }
            $label = trim((string)($item['label'] ?? ''));
            $threshold = max(0.0, (float)($item['threshold'] ?? 0));
            $multiplier = (float)($item['multiplier'] ?? 0);
            if ($label === '' || $multiplier <= 0) {
                continue;
            }
            $tiers[] = [
                'code' => strtolower((string)preg_replace('/[^a-z0-9]+/i', '_', $label)),
                'label' => $label,
                'threshold' => $threshold,
                'multiplier' => $multiplier,
            ];
        }

        if (!$tiers) {
            $tiers = [
                ['code' => 'bronze', 'label' => 'Bronze Maker', 'threshold' => 0.0, 'multiplier' => 1.0],
                ['code' => 'silver', 'label' => 'Silver Maker', 'threshold' => $this->silverThreshold($storeId), 'multiplier' => $this->silverMultiplier($storeId)],
                ['code' => 'gold', 'label' => 'Gold Maker', 'threshold' => $this->goldThreshold($storeId), 'multiplier' => $this->goldMultiplier($storeId)],
            ];
        }

        usort($tiers, static fn(array $left, array $right): int => $left['threshold'] <=> $right['threshold']);
        return $tiers;
    }

    private function value(string $path, ?int $storeId): mixed { return $this->scopeConfig->getValue('esun_reward/' . $path, ScopeInterface::SCOPE_STORE, $storeId); }
    private function int(string $path, ?int $storeId): int { return max(0, (int)$this->value($path, $storeId)); }
    private function float(string $path, ?int $storeId): float { return max(0.0, (float)$this->value($path, $storeId)); }
    private function flag(string $path, ?int $storeId): bool { return $this->scopeConfig->isSetFlag('esun_reward/' . $path, ScopeInterface::SCOPE_STORE, $storeId); }
}