<?php

/**
 * PurchaseInvoiceInstallment
 *
 * CRON scheduler untuk membuat baris cicilan otomatis ke tabel supplier_installment
 * setiap bulan berdasarkan kontrak aset yang aktif dan belum lunas.
 *
 * Endpoint:
 *   POST /scheduler/PurchaseInvoiceInstallment/GenerateMonthlyInvoices
 */
class PurchaseInvoiceInstallment extends MY_Controller
{
    var $db;

    public function index()
    {
        echo "Purchase Invoice Installment — Auto Generate Installment Cicilan Aset";
    }

    public function __construct()
    {
        parent::__construct();
    }

    /**
     * GenerateMonthlyInvoices — Step 6
     *
     * Creates supplier_installment rows for all eligible contracts this month.
     * No journal is created here — that happens at cashier payment time.
     * Contract InstallmentPaid is NOT updated here — that happens at payment time.
     *
     * Called by CRON daily at 1:00 AM.
     * Defaults to current month if no startDate/endDate provided.
     */
    public function GenerateMonthlyInvoices()
    {
        try {
            $para = $this->sys_input;

            $userID = !empty($this->sys_user["M_UserID"])
                ? (int) $this->sys_user["M_UserID"]
                : 0;

            $startDate = !empty($para["startDate"])
                ? $para["startDate"]
                : date("Y-m-01");

            $endDate = !empty($para["endDate"])
                ? $para["endDate"]
                : date("Y-m-t");

            if (!$this->isValidDate($startDate) || !$this->isValidDate($endDate)) {
                throw new Exception("Format tanggal tidak valid.");
            }

            if (strtotime($startDate) > strtotime($endDate)) {
                throw new Exception("startDate > endDate.");
            }

            // ── Steps 1–5: Get eligible contracts ────────────────────
            $eligible = $this->getEligibleInstallments($startDate, $endDate);

            $created  = [];
            $inserted = 0;

            $this->db->trans_begin();

            foreach ($eligible as $row) {

                $amount      = (float) $row["PurchaseOrderAssetContractInstallmentPayAmount"];
                $dayOfMonth  = (int) ($row["PurchaseOrderAssetContractInstallmentDate"] ?? 1);
                $lastDay     = (int) date("t", strtotime($endDate));
                $dayOfMonth  = min($dayOfMonth, $lastDay);
                $installDate = date("Y-m", strtotime($endDate)) . "-" . str_pad($dayOfMonth, 2, "0", STR_PAD_LEFT);
                $dueDate     = date("Y-m-d", strtotime($installDate . " +7 days"));
                $createdBy   = (int) ($row["PurchaseOrderAssetContractCreatedUserID"] ?? $userID);

                // ── Step 6: INSERT supplier_installment ──────────────
                $sql = "INSERT INTO supplier_installment (
                        SupplierInstallmentPurchaseOrderID,
                        SupplierInstallmentSupplierID,
                        SupplierInstallmentSupplierInvoiceID,
                        SupplierInstallmentAmount,
                        SupplierInstallmentDate,
                        SupplierInstallmentDueDate,
                        SupplierInstallmentPaymentID,
                        SupplierInstallmentStatus,
                        SupplierInstallmentIsLunas,
                        SupplierInstallmentIsActive,
                        SupplierInstallmentCreated,
                        SupplierInstallmentCreatedUserID
                    ) VALUES (?, ?, ?, ?, ?, ?, 0, 'Pending', 'N', 'Y', NOW(), ?)";

                $que = $this->db->query($sql, [
                    $row["PurchaseOrderID"],
                    $row["PurchaseOrderSupplierID"],
                    $row["SupplierInvoiceID"],
                    $amount,
                    $installDate,
                    $dueDate,
                    $createdBy
                ]);

                if (!$que) {
                    $this->db->trans_rollback();
                    $this->sys_error_db("Gagal insert supplier_installment.");
                    exit;
                }

                $installmentID = $this->db->insert_id();
                $inserted++;

                $created[] = [
                    "installmentID"       => $installmentID,
                    "contractID"          => $row["PurchaseOrderAssetContractID"],
                    "purchaseOrderID"     => $row["PurchaseOrderID"],
                    "parentInvoiceID"     => $row["SupplierInvoiceID"],
                    "parentInvoiceNumber" => $row["SupplierInvoiceNumber"],
                    "amount"              => $amount,
                    "installDate"         => $installDate,
                    "dueDate"             => $dueDate
                ];
            }

            if ($this->db->trans_status() === false) {
                $this->db->trans_rollback();
                $this->sys_error_db("Transaksi gagal.");
                exit;
            }

            $this->db->trans_commit();

            $this->sys_ok([
                "startDate"      => $startDate,
                "endDate"        => $endDate,
                "totalEligible"  => count($eligible),
                "totalInserted"  => $inserted,
                "created"        => $created
            ]);

        } catch (Exception $exc) {
            if ($this->db->trans_status() === false) {
                $this->db->trans_rollback();
            }
            $this->sys_error($exc->getMessage());
        }
    }

    /**
     * Ambil data user berdasarkan userID untuk keperluan CRON.
     * Jika user tidak ditemukan, kembalikan data default (tanpa branch/regional).
     *
     * @param int $userID
     * @return array
     */
    private function getCronUser($userID)
    {
        $sql = "SELECT
                M_UserID,
                M_UserM_BranchID   AS M_BranchID,
                M_UserS_RegionalID AS S_RegionalID
            FROM m_user
            WHERE M_UserID = ?
            LIMIT 1";

        $qry = $this->db->query($sql, [$userID]);
        if ($qry && $qry->num_rows() > 0) {
            $user = $qry->row_array();
            $user["loginLevel"] = "branch";
            return $user;
        }

        // User tidak ditemukan, gunakan data kosong agar proses tetap berjalan
        return [
            "M_UserID"     => $userID,
            "M_BranchID"   => 0,
            "S_RegionalID" => 0,
            "loginLevel"   => "branch"
        ];
    }

    /**
     * Hitung tanggal jatuh tempo berdasarkan tanggal acuan dan payment term (dalam hari).
     *
     * @param string $tanggal  Format YYYY-MM-DD
     * @param int    $term     Jumlah hari payment term
     * @return string          Tanggal jatuh tempo (YYYY-MM-DD)
     */
    private function hitungJatuhTempo($tanggal, $term)
    {
        $hari = is_numeric($term) ? (int) $term : 0;
        if ($hari < 0) {
            $hari = 0;
        }

        return date("Y-m-d", strtotime($tanggal . " +" . $hari . " days"));
    }

    /**
     * Validasi apakah string adalah tanggal yang valid dengan format YYYY-MM-DD.
     *
     * @param string $tanggal
     * @return bool
     */
    private function isValidDate($tanggal)
    {
        $d = DateTime::createFromFormat("Y-m-d", $tanggal);
        return $d && $d->format("Y-m-d") === $tanggal;
    }

    /**
     * getEligibleInstallments — Steps 1–5 combined
     *
     * Returns contracts that:
     *   Step 1: Are active, not paid off, within date range, due date reached
     *   Step 2: Have approved & active PO
     *   Step 3: Have confirmed & active RO
     *   Step 4: Have a parent supplier_invoice with IsInstallment = 'Y'
     *   Step 5: Do NOT already have a supplier_installment for this month
     *
     * @param string $startDate  YYYY-MM-DD
     * @param string $endDate    YYYY-MM-DD
     * @return array
     */
    private function getEligibleInstallments($startDate, $endDate)
    {
        $dayOfMonth = (int) date("d", strtotime($endDate));

        $sql = "SELECT
                c.PurchaseOrderAssetContractID,
                c.PurchaseOrderAssetContractInstallmentPayAmount,
                c.PurchaseOrderAssetContractInstallmentDate,
                c.PurchaseOrderAssetContractCreatedUserID,
                po.PurchaseOrderID,
                po.PurchaseOrderSupplierID,
                si.SupplierInvoiceID,
                si.SupplierInvoiceNumber
            FROM purchase_order_asset_contract c

            -- Step 2: PO must be Approved and Active
            JOIN purchase_order po
                ON po.PurchaseOrderID = c.PurchaseOrderAssetContractPurchaseOrderID
                AND po.PurchaseOrderIsActive = 'Y'
                AND po.PurchaseOrderStatus = 'Approved'

            -- Step 3: RO must be Confirmed and Active
            JOIN (
                SELECT
                    rd.ReceiveOrderPoDetailPurchaseOrderID,
                    MIN(ro0.ReceiveOrderPoID)        AS ReceiveOrderPoID,
                    MAX(ro0.ReceiveOrderPoConfirmed)  AS ReceiveOrderPoConfirmed
                FROM receive_order_po ro0
                JOIN receive_order_po_detail rd
                    ON rd.ReceiveOrderPoDetailReceiveOrderPoID = ro0.ReceiveOrderPoID
                    AND rd.ReceiveOrderPoDetailIsActive = 'Y'
                WHERE ro0.ReceiveOrderPoIsActive = 'Y'
                    AND ro0.ReceiveOrderPoConfirmed = 'Y'
                GROUP BY rd.ReceiveOrderPoDetailPurchaseOrderID
            ) ro ON ro.ReceiveOrderPoDetailPurchaseOrderID = po.PurchaseOrderID

            -- Step 4: Parent invoice must exist with IsInstallment = 'Y'
            JOIN supplier_invoice si
                ON si.SupplierInvoiceReceiveOrderPoID = ro.ReceiveOrderPoID
                AND si.SupplierInvoiceIsActive = 'Y'
                AND si.SupplierInvoiceIsInstallment = 'Y'

            -- Step 1: Contract eligibility
            WHERE c.PurchaseOrderAssetContractIsActive = 'Y'
                AND c.PurchaseOrderAssetContractStatus = 'belum lunas'
                AND IFNULL(c.PurchaseOrderAssetContractInstallmentPayAmount, 0) > 0
                AND IFNULL(c.PurchaseOrderAssetContractInstallmentPaid, 0)
                    < IFNULL(c.PurchaseOrderAssetContractInstallmentNumber, 0)
                AND DATE(c.PurchaseOrderAssetContractStartDate) <= DATE(?)
                AND (
                    c.PurchaseOrderAssetContractEndDate IS NULL
                    OR DATE(c.PurchaseOrderAssetContractEndDate) >= DATE(?)
                )
                AND IFNULL(c.PurchaseOrderAssetContractInstallmentDate, 1) <= ?

            -- Step 5: Dedup — no existing supplier_installment this month (any status)
            AND NOT EXISTS (
                SELECT 1
                FROM supplier_installment inst
                WHERE inst.SupplierInstallmentIsActive = 'Y'
                    AND inst.SupplierInstallmentPurchaseOrderID = po.PurchaseOrderID
                    AND DATE_FORMAT(inst.SupplierInstallmentDate, '%Y-%m') = DATE_FORMAT(?, '%Y-%m')
            )

            ORDER BY c.PurchaseOrderAssetContractID ASC";

        $params = [$endDate, $startDate, $dayOfMonth, $endDate];

        $qry = $this->db->query($sql, $params);
        if (!$qry) {
            $this->sys_error_db("Gagal mengambil daftar installment eligible.");
            exit;
        }

        return $qry->result_array();
    }
}