<?php
declare(strict_types=1);

namespace App\Modules\Subscriptions\Services;

use App\Core\App;
use App\Core\Logger;
use App\Modules\Rules\Services\RuleEngine;

final class SubscriptionGenerator
{
    public static function generateForYear(string $financialYear, ?int $branchId = null): array
    {
        $db = App::getInstance()->db();
        $employee = App::getInstance()->currentEmployee();
        $ts = date('Y-m-d H:i:s');
        $empId = $employee ? (int) $employee->id : null;

        // Get year-specific rates (e.g. 2024/2025 -> suffix 2024)
        $yearParts = explode('/', $financialYear);
        $yearSuffix = $yearParts[0] ?? '';
        $memberRate = self::getRate('SVC_ANNUAL_MEMBER_' . $yearSuffix) ?: self::getRate('SVC_ANNUAL_MEMBER');
        $spouseRate = self::getRate('SVC_ANNUAL_SPOUSE_' . $yearSuffix) ?: self::getRate('SVC_ANNUAL_SPOUSE');
        $childRate = self::getRate('SVC_ANNUAL_CHILD_' . $yearSuffix) ?: self::getRate('SVC_ANNUAL_CHILD');
        $tempRate = self::getRate('SVC_ANNUAL_TEMP_' . $yearSuffix) ?: self::getRate('SVC_ANNUAL_TEMP');
        $devFeeData = RuleEngine::get('DEVELOPMENT_FEE');
        $devFee = $devFeeData['amount'] ?? '35.00';

        // Year-specific discount: applied on final total (base + dev fee) per row
        $yearAdjustment = RuleEngine::get('SUBSCRIPTION_YEAR_ADJUSTMENT_' . $yearSuffix);
        $discountPct = null;
        if ($yearAdjustment && isset($yearAdjustment['discount_percentage'])) {
            $discountPct = $yearAdjustment['discount_percentage'];
        }

        // Get exempt membership types from subscription_rate_overrides
        $exemptTypes = [];
        try {
            $overrides = $db->select(
                "SELECT membership_type FROM subscription_rate_overrides WHERE financial_year = ? AND is_exempt = 1",
                [$financialYear]
            );
            foreach ($overrides as $o) {
                $exemptTypes[] = $o['membership_type'];
            }
        } catch (\Throwable $e) {
            $exemptTypes = ['honorary', 'seasonal'];
        }
        if (empty($exemptTypes)) {
            $exemptTypes = ['honorary', 'seasonal'];
        }

        $excludePlaceholders = implode(',', array_fill(0, count($exemptTypes), '?'));
        $memberWhere = "m.status = 'active' AND m.is_archived = 0 AND m.membership_type NOT IN ({$excludePlaceholders})";
        $memberParams = $exemptTypes;
        if ($branchId) {
            $memberWhere .= ' AND m.branch_id = ?';
            $memberParams[] = $branchId;
        }

        $members = $db->select("SELECT m.id, m.full_name_ar, m.membership_number FROM members m WHERE {$memberWhere}", $memberParams);

        $created = 0;
        $skipped = 0;

        foreach ($members as $member) {
            $memberId = (int) $member['id'];

            // Check if already generated
            $existing = $db->selectOne(
                "SELECT id FROM subscriptions WHERE member_id = ? AND financial_year = ? AND person_type = 'member'",
                [$memberId, $financialYear]
            );
            if ($existing) { $skipped++; continue; }

            // Member subscription — discount on base only; dev fee is separate non-discountable charge
            $discount = $discountPct ? bcdiv(bcmul($memberRate, $discountPct, 4), '100', 2) : '0.00';
            $total = bcsub($memberRate, $discount, 2);
            $db->insert('subscriptions', [
                'member_id'       => $memberId,
                'financial_year'  => $financialYear,
                'person_type'     => 'member',
                'person_id'       => $memberId,
                'person_name'     => $member['full_name_ar'],
                'base_amount'     => $memberRate,
                'development_fee' => $devFee,
                'discount_amount' => $discount,
                'total_amount'    => $total,
                'status'          => 'pending',
                'created_at'      => $ts,
                'updated_at'      => $ts,
                'created_by'      => $empId,
            ]);
            $created++;

            // Spouses — NO dev fee
            if ($db->tableExists('spouses')) {
                $spouses = $db->select("SELECT id, full_name_ar FROM spouses WHERE member_id = ? AND is_archived = 0 AND status = 'active'", [$memberId]);
                foreach ($spouses as $sp) {
                    $existingSp = $db->selectOne(
                        "SELECT id FROM subscriptions WHERE member_id = ? AND financial_year = ? AND person_type = 'spouse' AND person_id = ?",
                        [$memberId, $financialYear, (int) $sp['id']]
                    );
                    if ($existingSp) { $skipped++; continue; }
                    $spDiscount = $discountPct ? bcdiv(bcmul($spouseRate, $discountPct, 4), '100', 2) : '0.00';
                    $spTotal = bcsub($spouseRate, $spDiscount, 2);
                    $db->insert('subscriptions', [
                        'member_id'       => $memberId,
                        'financial_year'  => $financialYear,
                        'person_type'     => 'spouse',
                        'person_id'       => (int) $sp['id'],
                        'person_name'     => $sp['full_name_ar'],
                        'base_amount'     => $spouseRate,
                        'development_fee' => '0.00',
                        'discount_amount' => $spDiscount,
                        'total_amount'    => $spTotal,
                        'status'          => 'pending',
                        'created_at'      => $ts,
                        'updated_at'      => $ts,
                        'created_by'      => $empId,
                    ]);
                    $created++;
                }
            }

            // Children — NO dev fee
            if ($db->tableExists('children')) {
                $children = $db->select("SELECT id, full_name_ar FROM children WHERE member_id = ? AND is_archived = 0 AND status = 'active'", [$memberId]);
                foreach ($children as $ch) {
                    $existingCh = $db->selectOne(
                        "SELECT id FROM subscriptions WHERE member_id = ? AND financial_year = ? AND person_type = 'child' AND person_id = ?",
                        [$memberId, $financialYear, (int) $ch['id']]
                    );
                    if ($existingCh) { $skipped++; continue; }
                    $chDiscount = $discountPct ? bcdiv(bcmul($childRate, $discountPct, 4), '100', 2) : '0.00';
                    $chTotal = bcsub($childRate, $chDiscount, 2);
                    $db->insert('subscriptions', [
                        'member_id'       => $memberId,
                        'financial_year'  => $financialYear,
                        'person_type'     => 'child',
                        'person_id'       => (int) $ch['id'],
                        'person_name'     => $ch['full_name_ar'],
                        'base_amount'     => $childRate,
                        'development_fee' => '0.00',
                        'discount_amount' => $chDiscount,
                        'total_amount'    => $chTotal,
                        'status'          => 'pending',
                        'created_at'      => $ts,
                        'updated_at'      => $ts,
                        'created_by'      => $empId,
                    ]);
                    $created++;
                }
            }

            // Temporary members — NO dev fee
            if ($db->tableExists('temporary_members')) {
                $temps = $db->select("SELECT id, full_name_ar FROM temporary_members WHERE member_id = ? AND is_archived = 0 AND status = 'active'", [$memberId]);
                foreach ($temps as $t) {
                    $existingTmp = $db->selectOne(
                        "SELECT id FROM subscriptions WHERE member_id = ? AND financial_year = ? AND person_type = 'temporary' AND person_id = ?",
                        [$memberId, $financialYear, (int) $t['id']]
                    );
                    if ($existingTmp) { $skipped++; continue; }
                    $tmpDiscount = $discountPct ? bcdiv(bcmul($tempRate, $discountPct, 4), '100', 2) : '0.00';
                    $tmpTotal = bcsub($tempRate, $tmpDiscount, 2);
                    $db->insert('subscriptions', [
                        'member_id'       => $memberId,
                        'financial_year'  => $financialYear,
                        'person_type'     => 'temporary',
                        'person_id'       => (int) $t['id'],
                        'person_name'     => $t['full_name_ar'],
                        'base_amount'     => $tempRate,
                        'development_fee' => '0.00',
                        'discount_amount' => $tmpDiscount,
                        'total_amount'    => $tmpTotal,
                        'status'          => 'pending',
                        'created_at'      => $ts,
                        'updated_at'      => $ts,
                        'created_by'      => $empId,
                    ]);
                    $created++;
                }
            }
        }

        Logger::info("Subscription batch generated", ['year' => $financialYear, 'created' => $created, 'skipped' => $skipped]);

        return ['created' => $created, 'skipped' => $skipped, 'members_processed' => count($members)];
    }

    private static function getRate(string $serviceCode): string
    {
        $db = App::getInstance()->db();
        $row = $db->selectOne(
            "SELECT base_amount FROM service_catalog WHERE service_code = ? AND is_active = 1 AND branch_id IS NULL ORDER BY effective_from DESC LIMIT 1",
            [$serviceCode]
        );
        return $row['base_amount'] ?? '0.00';
    }
}