/**
 * routes/reports.mjs — Reports (trial balance, etc.)
 */

export default function registerReports(app, pool) {
  // GET /api/ledger/trial-balance — Saldobalans
  app.get('/api/ledger/trial-balance', async (req, res) => {
    const tenant_id = req.headers['x-tenant-id'] || 'wavult-group';
    const { period, period_from, period_to, fiscal_year } = req.query;
    if (!fiscal_year) return res.status(400).json({ ok: false, error: 'fiscal_year krävs' });

    try {
      const conditions = ['e.tenant_id=$1', 'e.fiscal_year=$2', "e.status='posted'"];
      const params = [tenant_id, parseInt(fiscal_year)];
      let pidx = 3;
      if (period) {
        conditions.push(`e.period=$${pidx++}`); params.push(period);
      } else if (period_from && period_to) {
        conditions.push(`e.period>=$${pidx++}`); params.push(period_from);
        conditions.push(`e.period<=$${pidx++}`); params.push(period_to);
      } else if (period_from) {
        conditions.push(`e.period>=$${pidx++}`); params.push(period_from);
      } else if (period_to) {
        conditions.push(`e.period<=$${pidx++}`); params.push(period_to);
      }

      const { rows } = await pool.query(
        `SELECT
           l.account_number,
           MAX(l.account_name)        AS account_name,
           COALESCE(SUM(l.debit), 0)  AS total_debit,
           COALESCE(SUM(l.credit), 0) AS total_credit,
           COALESCE(SUM(l.debit), 0) - COALESCE(SUM(l.credit), 0) AS balance
         FROM ledger_journal_lines l
         JOIN ledger_journal_entries e ON e.id = l.entry_id
         WHERE ${conditions.join(' AND ')}
         GROUP BY l.account_number
         ORDER BY l.account_number`,
        params
      );

      const totalDebit  = rows.reduce((s,r) => s + parseFloat(r.total_debit),  0);
      const totalCredit = rows.reduce((s,r) => s + parseFloat(r.total_credit), 0);

      res.json({
        ok: true,
        fiscal_year: parseInt(fiscal_year),
        period: period || 'all',
        accounts: rows,
        totals: { debit: totalDebit, credit: totalCredit, balanced: Math.abs(totalDebit - totalCredit) < 0.01 }
      });
    } catch (e) {
      res.status(500).json({ ok: false, error: e.message });
    }
  });
}