import { Migration } from '@mikro-orm/migrations';

export class Migration20260524120000 extends Migration {

  override async up(): Promise<void> {
    this.addSql(`
    CREATE OR REPLACE FUNCTION recalc_invoice_totals()
    RETURNS TRIGGER AS $$
    DECLARE
        v_invoice_id char(26);
        v_subtotal int;
        v_discount int;
        v_tax int;
        v_total int;
        v_paid int;
        v_enable_tax boolean;
    BEGIN

        v_invoice_id := COALESCE(NEW.invoice_id, OLD.invoice_id);

        SELECT
            COALESCE(SUM(sub_total),0),
            COALESCE(SUM(discount),0)
        INTO
            v_subtotal,
            v_discount
        FROM invoice_items
        WHERE invoice_id = v_invoice_id
        AND deleted_at IS NULL;

        SELECT enable_tax
        INTO v_enable_tax
        FROM invoices
        WHERE id = v_invoice_id;

        IF v_enable_tax THEN
            v_tax := (v_subtotal - v_discount) * 0.10;
        ELSE
            v_tax := 0;
        END IF;

        v_total := (v_subtotal - v_discount) + v_tax;

        SELECT COALESCE(SUM(amount),0)::int
        INTO v_paid
        FROM payments
        WHERE invoice_id = v_invoice_id
        AND status = 'paid'
        AND deleted_at IS NULL;

        UPDATE invoices
        SET
            sub_total = v_subtotal,
            discount = v_discount,
            tax_amount = v_tax,
            total = v_total,
            paid_amount = v_paid,
            balance = v_total - v_paid
        WHERE id = v_invoice_id;

        RETURN NULL;
    END;
    $$ LANGUAGE plpgsql;
    `);

    this.addSql(`
    CREATE OR REPLACE FUNCTION recalc_invoice_payments()
    RETURNS TRIGGER AS $$
    DECLARE
        v_invoice_id char(26);
        v_paid int;
        v_total int;
    BEGIN

        v_invoice_id := COALESCE(NEW.invoice_id, OLD.invoice_id);

        SELECT COALESCE(SUM(amount),0)::int
        INTO v_paid
        FROM payments
        WHERE invoice_id = v_invoice_id
        AND status = 'paid'
        AND deleted_at IS NULL;

        SELECT total
        INTO v_total
        FROM invoices
        WHERE id = v_invoice_id;

        UPDATE invoices
        SET
            paid_amount = v_paid,
            balance = v_total - v_paid
        WHERE id = v_invoice_id;

        RETURN NULL;
    END;
    $$ LANGUAGE plpgsql;
    `);

    this.addSql(`
    UPDATE invoices i
    SET
        paid_amount = COALESCE(p.paid_sum, 0),
        balance = i.total - COALESCE(p.paid_sum, 0)
    FROM (
        SELECT invoice_id, SUM(amount)::int AS paid_sum
        FROM payments
        WHERE status = 'paid'
        AND deleted_at IS NULL
        GROUP BY invoice_id
    ) p
    WHERE i.id = p.invoice_id;
    `);
  }

  override async down(): Promise<void> {
    // Restore previous (broken) function bodies from Migration20260404083020
    this.addSql(`
    CREATE OR REPLACE FUNCTION recalc_invoice_totals()
    RETURNS TRIGGER AS $$
    DECLARE
        v_invoice_id char(26);
        v_subtotal int;
        v_discount int;
        v_tax int;
        v_total int;
        v_paid int;
        v_enable_tax boolean;
    BEGIN
        v_invoice_id := COALESCE(NEW.invoice_id, OLD.invoice_id);
        SELECT COALESCE(SUM(sub_total),0), COALESCE(SUM(discount),0)
        INTO v_subtotal, v_discount
        FROM invoice_items
        WHERE invoice_id = v_invoice_id AND deleted_at IS NULL;
        SELECT enable_tax INTO v_enable_tax FROM invoices WHERE id = v_invoice_id;
        IF v_enable_tax THEN
            v_tax := (v_subtotal - v_discount) * 0.10;
        ELSE
            v_tax := 0;
        END IF;
        v_total := (v_subtotal - v_discount) + v_tax;
        SELECT COALESCE(SUM(amount),0) INTO v_paid
        FROM payments
        WHERE invoice_id = v_invoice_id AND status = 'SUCCESS';
        UPDATE invoices SET sub_total = v_subtotal, discount = v_discount, tax_amount = v_tax,
            total = v_total, paid_amount = v_paid, balance = v_total - v_paid
        WHERE id = v_invoice_id;
        RETURN NULL;
    END;
    $$ LANGUAGE plpgsql;
    `);

    this.addSql(`
    CREATE OR REPLACE FUNCTION recalc_invoice_payments()
    RETURNS TRIGGER AS $$
    DECLARE
        v_invoice_id char(26);
        v_paid int;
        v_total int;
    BEGIN
        v_invoice_id := COALESCE(NEW.invoice_id, OLD.invoice_id);
        SELECT COALESCE(SUM(amount),0) INTO v_paid
        FROM payments WHERE invoice_id = v_invoice_id AND status = 'SUCCESS';
        SELECT total INTO v_total FROM invoices WHERE id = v_invoice_id;
        UPDATE invoices SET paid_amount = v_paid, balance = v_total - v_paid
        WHERE id = v_invoice_id;
        RETURN NULL;
    END;
    $$ LANGUAGE plpgsql;
    `);
  }

}