<?php
require_once __DIR__ . '/BasePosting.php';

class ReceiptPosting extends BasePosting
{
    protected function getDocType(): string { return 'receipt'; }

    public function build(int $id, ?int $formula_id = null): array
    {
        $doc = $this->fetchDocument($id);
        $formula = $this->resolveFormula($this->getDocType(), $formula_id);
        $doc_date = $this->getDocDate($doc);
        $period = substr($doc_date, 0, 7);
        $dept_amounts = $this->getDepartmentAmounts($id);

        $lines = [];
        foreach ($dept_amounts as $dept_id => $amount) {
            if (abs($amount) <= 0.0001) continue;
            $is_negative = $amount < 0;
            $line_amount = abs($amount);

            foreach ($formula['items'] as $item) {
                if ($item['amount_key'] === 'tax') continue;

                $drcr = $item['drcr'];
                if ($is_negative) {
                    $drcr = $drcr === 'D' ? 'C' : 'D';
                }

                $lines[] = [
                    'account_code' => $item['account_code'],
                    'department_id' => (int)$dept_id,
                    'debit'        => $drcr === 'D' ? $line_amount : 0.0,
                    'credit'       => $drcr === 'C' ? $line_amount : 0.0,
                    'description'  => (string)($item['description'] ?? ''),
                ];
            }
        }

        return [
            'formula_id' => (int)$formula['id'],
            'period'     => $period,
            'doc_date'   => $doc_date,
            'lines'      => $lines,
        ];
    }

    protected function fetchDocument(int $id): array
    {
        $sth = $this->pdo->prepare(
            "SELECT r.*, COALESCE(c.contact_name, '') AS contact_name
             FROM td_receipt r
             LEFT JOIN md_contact c
               ON c.company_id = r.company_id AND c.id = r.contact_id
             WHERE r.company_id = :cid AND r.id = :id
             LIMIT 1"
        );
        $sth->execute([':cid' => $this->companyId, ':id' => $id]);
        $doc = $sth->fetch(PDO::FETCH_ASSOC);
        if (!$doc) throw new Exception("Receipt #{$id} not found.");
        return $doc;
    }

    protected function getAmounts(array $doc): array
    {
        $amount = abs((float)$doc['amount']);
        return [
            'amount'      => $amount,
            'grand_total' => $amount,
            'total'       => $amount,
            'tax'         => 0.0,
        ];
    }

    protected function getDocDate(array $doc): string
    {
        return $doc['receipt_date'] ?? date('Y-m-d');
    }

    private function getDepartmentAmounts(int $receipt_id): array
    {
        $sth = $this->pdo->prepare(
            "SELECT ri.department_id,
                    ri.doc_type,
                    ri.amount
             FROM td_receipt_item ri
             WHERE ri.company_id = :cid
               AND ri.receipt_id = :receipt_id"
        );
        $sth->execute([
            ':cid'        => $this->companyId,
            ':receipt_id' => $receipt_id,
        ]);

        $dept_amounts = [];
        foreach ($sth->fetchAll(PDO::FETCH_ASSOC) as $line) {
            $dept_id = (int)($line['department_id'] ?? 0);
            $amount = abs((float)($line['amount'] ?? 0));
            if ($line['doc_type'] === 'credit_note') {
                $amount *= -1;
            }
            $dept_amounts[$dept_id] = ($dept_amounts[$dept_id] ?? 0) + $amount;
        }

        if (!$dept_amounts) throw new Exception("Receipt #{$receipt_id} has no allocation lines for GL posting.");

        return $dept_amounts;
    }
}