/* @tier easy @module st @transform settlement-online */
/*
 * st_ol_0017.pgc - 구간요율 수수료율 적용 (ST_OL_0017)  [tier=easy]
 *
 * 거래금액 구간(band)별 차등 수수료율(만분율)을 적용하여 수수료를
 * 산출한다. 소액/중액/고액 슬라브 요율 모델. 구간요율표(st_band_rate)
 * 를 조회하여 해당 금액이 속한 구간의 요율을 적용한다.
 */
#include <stdio.h>
#include <string.h>

#include "txcore.h"
#include "txcore_dbio.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_0017, ctx)
{
    EXEC SQL BEGIN DECLARE SECTION;
    long h_amount;
    long h_bp;
    char h_band[8];
    EXEC SQL END DECLARE SECTION;

    char merch[16];
    long amount = 0, bp, fee, net;
    char band[8] = "-";

    tx_log(TX_LOG_INFO, "[ST_OL_0017] 구간요율 적용 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);
    if (!amount_is_valid(amount)) {
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_INVALID);
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }

    /* 구간요율표에서 금액이 속한 구간 요율 조회 */
    h_amount = amount;
    h_bp = 0;
    memset(h_band, 0, sizeof(h_band));
    EXEC SQL SELECT rate_bp, band_code
        INTO :h_bp, :h_band
        FROM st_band_rate
        WHERE :h_amount >= lo_amt
          AND :h_amount <  hi_amt;

    if (sqlca.sqlcode == TX_SQL_OK && h_bp > 0) {
        bp = h_bp;
        strncpy(band, h_band, sizeof(band) - 1);
        band[sizeof(band) - 1] = '\0';
    } else {
        if (sqlca.sqlcode != TX_SQL_OK && sqlca.sqlcode != TX_SQL_NOTFOUND)
            TX_DBIO_LOG_ERR("SELECT st_band_rate");
        /* 미등록 구간 폴백: 내장 슬라브 요율 */
        if (amount < 50000L)       { bp = 250; strcpy(band, "LOW"); }
        else if (amount < 500000L) { bp = 180; strcpy(band, "MID"); }
        else                       { bp = 140; strcpy(band, "HIGH"); }
    }

    fee = st_fee_round(amount, 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_sets(ctx->out, "BAND", band);
    tx_buf_setlong(ctx->out, "AMOUNT", amount);
    tx_buf_setlong(ctx->out, "BPUSED", bp);
    tx_buf_setlong(ctx->out, "FEE", fee);
    tx_buf_setlong(ctx->out, "NET", net);
    tx_log(TX_LOG_INFO, "[ST_OL_0017] 구간요율 amount=%ld band=%s bp=%ld fee=%ld",
           amount, band, bp, fee);
    tx_return(ctx, TX_OK, ctx->out);
}
