/* @tier easy @module st @transform settlement-online */
/*
 * st_ol_0003.pgc - 가맹점 할인수수료(MDR) 계산 (ST_OL_0003)  [tier=easy]
 *
 * 가맹점 거래금액에 MDR(가맹점 할인수수료) 요율(만분율)을 적용하여
 * 수수료와 정산순액(net)을 원단위 반올림으로 산출한다.
 */
#include <stdio.h>
#include <string.h>

#include "txcore.h"
#include "acq_util.h"
#include "st_core.h"

EXEC SQL INCLUDE sqlca;


static long st_fee_round(long amount, long rate_bp)
{
    /* 요율(만분율, basis point) x 금액 -> 원단위 반올림 (BigDecimal HALF_UP 대응) */
    if (amount < 0)
        return -(((-amount) * rate_bp + 5000) / 10000);
    return (amount * rate_bp + 5000) / 10000;
}

TX_SERVICE(ST_OL_0003, ctx)
{
    char merch[16];
    long amount = 0, mdr_bp = 0, fee, net;

    tx_log(TX_LOG_INFO, "[ST_OL_0003] MDR 수수료 계산 진입");

    if (tx_buf_get(ctx->in, "MERCHID", merch, sizeof(merch)) != TX_OK) {
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }
    tx_buf_getlong(ctx->in, "AMOUNT", &amount);
    tx_buf_getlong(ctx->in, "MDRBP",  &mdr_bp);

    if (!amount_is_valid(amount) || mdr_bp <= 0 || mdr_bp > 10000) {
        tx_log(TX_LOG_WARN, "[ST_OL_0003] 요율/금액 오류 amount=%ld bp=%ld", amount, mdr_bp);
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_INVALID);
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }

    fee = st_fee_round(amount, mdr_bp);
    net = amount - fee;

    tx_buf_reset(ctx->out);
    tx_buf_sets(ctx->out, "RESPCODE", RESP_OK);
    tx_buf_sets(ctx->out, "MERCHID", merch);
    tx_buf_setlong(ctx->out, "AMOUNT", amount);
    tx_buf_setlong(ctx->out, "MDRBP", mdr_bp);
    tx_buf_setlong(ctx->out, "FEE", fee);
    tx_buf_setlong(ctx->out, "NET", net);
    tx_log(TX_LOG_INFO, "[ST_OL_0003] MDR 산출 amount=%ld bp=%ld fee=%ld net=%ld",
           amount, mdr_bp, fee, net);
    tx_return(ctx, TX_OK, ctx->out);
}
