<?php

namespace Modules\Accounting\Services;

use Carbon\Carbon;
use Illuminate\Support\Facades\DB;
use Illuminate\Support\Facades\Schema;
use Modules\Accounting\Entities\AccountingAccTransMapping;
use Modules\Accounting\Entities\AccountingCheque;
use Modules\Accounting\Entities\AccountingInstallmentSchedule;

class DeferredDocumentsService
{
    public function summary(int $businessId): array
    {
        $cheques = $this->pendingChequeCount($businessId);
        $installments = $this->overdueInstallmentCount($businessId);
        $invoices = $this->overdueInvoiceCount($businessId);
        $journals = $this->pendingJournalCount($businessId);

        return [
            'cheques' => $cheques,
            'installments' => $installments,
            'invoices' => $invoices,
            'journals' => $journals,
            'total' => $cheques + $installments + $invoices + $journals,
        ];
    }

    public function items(int $businessId): array
    {
        $items = [];

        foreach ($this->pendingCheques($businessId) as $cheque) {
            $items[] = [
                'type' => 'cheque',
                'type_label' => __('accounting::lang.cheques'),
                'reference' => $cheque->cheque_number,
                'party' => $cheque->bank_name ?: '-',
                'amount' => (float) $cheque->amount,
                'due_date' => optional($cheque->due_date)->format('Y-m-d'),
                'status' => $cheque->status,
                'url' => route('accounting.cheques'),
            ];
        }

        foreach ($this->overdueInstallments($businessId) as $row) {
            $outstanding = max(0, (float) $row->amount + (float) ($row->penalty_amount ?? 0) - (float) $row->paid_amount);
            $items[] = [
                'type' => 'installment',
                'type_label' => __('accounting::lang.installments'),
                'reference' => '#'.$row->installment_number,
                'party' => __('accounting::lang.installment_plan').' #'.$row->installment_plan_id,
                'amount' => $outstanding,
                'due_date' => $row->due_date,
                'status' => $row->status,
                'url' => route('accounting.installments'),
            ];
        }

        foreach ($this->overdueInvoices($businessId) as $invoice) {
            $items[] = [
                'type' => 'invoice',
                'type_label' => __('sale.invoice'),
                'reference' => $invoice->invoice_no,
                'party' => $invoice->contact_name ?? '-',
                'amount' => (float) $invoice->total_due,
                'due_date' => $invoice->due_date,
                'status' => $invoice->payment_status,
                'url' => action([\App\Http\Controllers\SellController::class, 'index']),
            ];
        }

        foreach ($this->pendingJournals($businessId) as $journal) {
            $items[] = [
                'type' => 'journal',
                'type_label' => __('accounting::lang.journal_entry'),
                'reference' => $journal->ref_no ?? '#'.$journal->id,
                'party' => $journal->note ?? '-',
                'amount' => null,
                'due_date' => optional($journal->operation_date)->format('Y-m-d'),
                'status' => $journal->approval_status,
                'url' => route('accounting.journalApprovals'),
            ];
        }

        return $items;
    }

    protected function pendingChequeCount(int $businessId): int
    {
        if (! Schema::hasTable('accounting_cheques')) {
            return 0;
        }

        return (int) AccountingCheque::where('business_id', $businessId)
            ->whereIn('status', ['pending', 'deposited'])
            ->where(function ($q) {
                $q->whereNull('due_date')
                    ->orWhereDate('due_date', '<=', Carbon::today()->toDateString());
            })
            ->count();
    }

    protected function overdueInstallmentCount(int $businessId): int
    {
        if (! Schema::hasTable('accounting_installment_schedule')) {
            return 0;
        }

        return (int) DB::table('accounting_installment_schedule as s')
            ->join('accounting_installment_plans as p', 'p.id', '=', 's.installment_plan_id')
            ->where('p.business_id', $businessId)
            ->whereIn('s.status', ['overdue', 'pending'])
            ->whereDate('s.due_date', '<', Carbon::today()->toDateString())
            ->count();
    }

    protected function overdueInvoiceCount(int $businessId): int
    {
        if (! Schema::hasTable('transactions') || ! Schema::hasColumn('transactions', 'due_date')) {
            return 0;
        }

        return (int) DB::table('transactions')
            ->where('business_id', $businessId)
            ->where('type', 'sell')
            ->where('status', 'final')
            ->whereIn('payment_status', ['due', 'partial'])
            ->whereNotNull('due_date')
            ->whereDate('due_date', '<', Carbon::today()->toDateString())
            ->count();
    }

    protected function pendingJournalCount(int $businessId): int
    {
        if (! Schema::hasTable('accounting_acc_trans_mappings') || ! Schema::hasColumn('accounting_acc_trans_mappings', 'approval_status')) {
            return 0;
        }

        return (int) AccountingAccTransMapping::where('business_id', $businessId)
            ->where('approval_status', 'pending')
            ->count();
    }

    protected function pendingCheques(int $businessId)
    {
        return AccountingCheque::where('business_id', $businessId)
            ->whereIn('status', ['pending', 'deposited'])
            ->where(function ($q) {
                $q->whereNull('due_date')
                    ->orWhereDate('due_date', '<=', Carbon::today()->toDateString());
            })
            ->orderBy('due_date')
            ->limit(100)
            ->get();
    }

    protected function overdueInstallments(int $businessId)
    {
        return DB::table('accounting_installment_schedule as s')
            ->join('accounting_installment_plans as p', 'p.id', '=', 's.installment_plan_id')
            ->where('p.business_id', $businessId)
            ->whereIn('s.status', ['overdue', 'pending'])
            ->whereDate('s.due_date', '<', Carbon::today()->toDateString())
            ->select('s.*')
            ->orderBy('s.due_date')
            ->limit(100)
            ->get();
    }

    protected function overdueInvoices(int $businessId)
    {
        return DB::table('transactions as t')
            ->leftJoin('contacts as c', 'c.id', '=', 't.contact_id')
            ->where('t.business_id', $businessId)
            ->where('t.type', 'sell')
            ->where('t.status', 'final')
            ->whereIn('t.payment_status', ['due', 'partial'])
            ->whereNotNull('t.due_date')
            ->whereDate('t.due_date', '<', Carbon::today()->toDateString())
            ->select(
                't.invoice_no',
                't.payment_status',
                't.due_date',
                'c.name as contact_name',
                DB::raw('(t.final_total - COALESCE((SELECT SUM(IF(tp.is_return=1,-1*tp.amount,tp.amount)) FROM transaction_payments tp WHERE tp.transaction_id=t.id),0)) as total_due')
            )
            ->orderBy('t.due_date')
            ->limit(100)
            ->get();
    }

    protected function pendingJournals(int $businessId)
    {
        return AccountingAccTransMapping::where('business_id', $businessId)
            ->where('approval_status', 'pending')
            ->orderByDesc('id')
            ->limit(50)
            ->get();
    }
}