/* @tier easy @module st @transform settlement-online */
/*
 * st_ol_0008.pgc - 정산 원천징수 계산 (ST_OL_0008)  [tier=easy]
 *
 * 사업소득 원천징수 3.3%(소득세 3% + 지방소득세 0.3%) 를 산출하고
 * 원천징수 후 실지급액을 계산한다. 가맹점 세무구분(st_merchant_tax)이
 * 원천징수 비대상이면 세액 0 으로 처리한다.
 */
#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_0008, ctx)
{
    EXEC SQL BEGIN DECLARE SECTION;
    char h_merch[16];
    char h_tax_type[2];
    long h_income_bp;
    EXEC SQL END DECLARE SECTION;

    char merch[16];
    long base = 0, income_tax, local_tax, withhold, payable, income_bp = 300;
    const char *tax_type = "B";

    tx_log(TX_LOG_INFO, "[ST_OL_0008] 원천징수 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, "BASE", &base);
    if (base < 0) {
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_INVALID);
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }

    /* 가맹점 세무구분/소득세율 조회 */
    strncpy(h_merch, merch, sizeof(h_merch) - 1);
    h_merch[sizeof(h_merch) - 1] = '\0';
    memset(h_tax_type, 0, sizeof(h_tax_type));
    h_income_bp = 0;
    EXEC SQL SELECT tax_type, income_bp
        INTO :h_tax_type, :h_income_bp
        FROM st_merchant_tax
        WHERE merch_id = :h_merch;
    if (sqlca.sqlcode == TX_SQL_OK) {
        tax_type = (h_tax_type[0] == 'C') ? "C" : "B";
        if (h_income_bp > 0) income_bp = h_income_bp;
    } else if (sqlca.sqlcode != TX_SQL_NOTFOUND) {
        TX_DBIO_LOG_ERR("SELECT st_merchant_tax");
    }

    if (strcmp(tax_type, "C") == 0) {
        /* 법인(C): 원천징수 비대상 */
        income_tax = 0;
        local_tax  = 0;
    } else {
        income_tax = st_fee_round(base, income_bp);       /* 소득세 */
        local_tax  = st_fee_round(income_tax, 1000);      /* 지방세 = 소득세의 10% */
    }
    withhold = income_tax + local_tax;
    payable  = base - withhold;

    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, "TAXTYPE", tax_type);
    tx_buf_setlong(ctx->out, "INCOMETAX", income_tax);
    tx_buf_setlong(ctx->out, "LOCALTAX", local_tax);
    tx_buf_setlong(ctx->out, "WITHHOLD", withhold);
    tx_buf_setlong(ctx->out, "PAYABLE", payable);
    tx_log(TX_LOG_INFO, "[ST_OL_0008] 원천징수 base=%ld 세액=%ld 실지급=%ld type=%s",
           base, withhold, payable, tax_type);
    tx_return(ctx, TX_OK, ctx->out);
}
