<?php
defined('BASEPATH') OR exit('No direct script access allowed');

class Migration_Create_account_budget_entries extends CI_Migration
{
    public function up()
    {
        if (!$this->db->table_exists('account_budget_entries')) {
            $this->db->query("CREATE TABLE `account_budget_entries` (
                `id` BIGINT UNSIGNED NOT NULL AUTO_INCREMENT,
                `company_id` BIGINT UNSIGNED NOT NULL,
                `account_id` INT NOT NULL,
                `period` CHAR(7) NOT NULL,
                `entry_type` ENUM('recurring','override') NOT NULL DEFAULT 'recurring',
                `amount` DECIMAL(18,2) NOT NULL DEFAULT 0,
                `notes` VARCHAR(255) NULL,
                `is_active` TINYINT(1) NOT NULL DEFAULT 1,
                `created_by` INT NULL,
                `created_at` DATETIME NOT NULL,
                `updated_by` INT NULL,
                `updated_at` DATETIME NULL,
                PRIMARY KEY (`id`),
                UNIQUE KEY `uq_account_budget_entry` (`company_id`,`account_id`,`period`,`entry_type`),
                KEY `idx_account_budget_period` (`company_id`,`period`,`account_id`,`is_active`),
                CONSTRAINT `fk_account_budget_account` FOREIGN KEY (`account_id`) REFERENCES `accounts` (`id`) ON UPDATE RESTRICT ON DELETE RESTRICT
            ) ENGINE=InnoDB DEFAULT CHARSET=utf8mb4 COLLATE=utf8mb4_unicode_ci");
        }

        // Pertahankan rincian budget aktif lama sebagai nilai khusus per bulan.
        if ($this->db->table_exists('budgets') && $this->db->table_exists('budget_lines')) {
            $this->db->query("INSERT IGNORE INTO account_budget_entries
                (company_id,account_id,period,entry_type,amount,notes,is_active,created_by,created_at)
                SELECT COALESCE(bl.company_id,b.company_id),bl.account_id,bl.period,'override',bl.amount,
                       CONCAT('Migrasi dari ',b.budget_no),1,b.created_by,COALESCE(bl.created_at,b.created_at,NOW())
                FROM budget_lines bl
                JOIN budgets b ON b.id=bl.budget_id
                WHERE b.status IN('active','approved') AND COALESCE(bl.company_id,b.company_id) IS NOT NULL");

            // Nilai bulan terakhir sampai bulan migrasi menjadi dasar berulang ke depan.
            $currentPeriod = date('Y-m');
            $this->db->query("INSERT IGNORE INTO account_budget_entries
                (company_id,account_id,period,entry_type,amount,notes,is_active,created_by,created_at)
                SELECT COALESCE(bl.company_id,b.company_id),bl.account_id,?,'recurring',bl.amount,
                       CONCAT('Budget berulang hasil migrasi ',b.budget_no),1,b.created_by,NOW()
                FROM budget_lines bl
                JOIN budgets b ON b.id=bl.budget_id
                JOIN (
                    SELECT COALESCE(bl2.company_id,b2.company_id) company_id,bl2.account_id,MAX(bl2.period) period
                    FROM budget_lines bl2 JOIN budgets b2 ON b2.id=bl2.budget_id
                    WHERE b2.status IN('active','approved') AND bl2.period<=?
                    GROUP BY COALESCE(bl2.company_id,b2.company_id),bl2.account_id
                ) latest ON latest.company_id=COALESCE(bl.company_id,b.company_id)
                         AND latest.account_id=bl.account_id AND latest.period=bl.period
                WHERE b.status IN('active','approved')", array($currentPeriod, $currentPeriod));
        }
    }

    public function down()
    {
        throw new RuntimeException('Gunakan backup database untuk rollback data budget per akun.');
    }
}