/* @tier medium @module st @transform settlement-online */
/*
 * st_ol_0018.pgc - 정산 상계(offset) 처리 (ST_OL_0018)  [tier=medium]
 *
 * 가맹점 채권(수취)과 채무(지급)를 상계하여 잔액과 방향을 산출한다.
 * 상계 후 잔여채권/잔여채무를 구분해 반환한다.
 */
#include <stdio.h>
#include <string.h>

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

EXEC SQL INCLUDE sqlca;


TX_SERVICE(ST_OL_0018, ctx)
{
    char merch[16];
    long receivable = 0, payable = 0, offset, residual;
    const char *dir;

    tx_log(TX_LOG_INFO, "[ST_OL_0018] 정산 상계 처리 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, "RECEIVABLE", &receivable);
    tx_buf_getlong(ctx->in, "PAYABLE",    &payable);
    if (receivable < 0 || payable < 0) {
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_INVALID);
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }

    offset   = (receivable < payable) ? receivable : payable;
    residual = receivable - payable;
    dir      = (residual > 0) ? "RECV" : (residual < 0 ? "PAY" : "EVEN");

    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, "OFFSET", offset);
    tx_buf_setlong(ctx->out, "RESIDUAL", residual);
    tx_buf_sets(ctx->out, "DIR", dir);
    tx_log(TX_LOG_INFO, "[ST_OL_0018] 상계 recv=%ld pay=%ld offset=%ld 잔액=%ld(%s)",
           receivable, payable, offset, residual, dir);
    tx_return(ctx, TX_OK, ctx->out);
}