/* @tier easy @module st @transform settlement-online */
/*
 * st_ol_0019.pgc - 정산 diff 검증(예상 vs 실제) (ST_OL_0019)  [tier=easy]
 *
 * 표준요율로 재산출한 예상 수수료와 원장에 기록된 실제 수수료의 차이를
 * 검증한다. 허용오차(tolerance)를 넘으면 불일치로 판정한다. 원장 금액/
 * 수수료는 st_ledger 에서 임베디드 조회한다.
 */
#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_0019, ctx)
{
    EXEC SQL BEGIN DECLARE SECTION;
    char h_key[16];
    long h_amount;
    long h_fee;
    EXEC SQL END DECLARE SECTION;

    char key[16];
    long std_bp = 0, tol = 0, expected, diff;
    int  mismatch;

    tx_log(TX_LOG_INFO, "[ST_OL_0019] 정산 diff 검증 진입");

    if (tx_buf_get(ctx->in, "KEY", key, sizeof(key)) != TX_OK) {
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }
    tx_buf_getlong(ctx->in, "STDBP", &std_bp);
    tx_buf_getlong(ctx->in, "TOL",   &tol);
    if (std_bp <= 0) std_bp = 180;      /* 표준요율 1.80% */
    if (tol < 0) tol = 0;

    /* 원장 금액/실제수수료 조회 */
    strncpy(h_key, key, sizeof(h_key) - 1);
    h_key[sizeof(h_key) - 1] = '\0';
    h_amount = 0;
    h_fee    = 0;
    EXEC SQL SELECT amount, fee
        INTO :h_amount, :h_fee
        FROM st_ledger
        WHERE key = :h_key;

    if (sqlca.sqlcode == TX_SQL_NOTFOUND) {
        tx_log(TX_LOG_WARN, "[ST_OL_0019] 원장 없음 key=%s", key);
        tx_return(ctx, TX_ENOENT, ctx->out);
        return;
    }
    if (sqlca.sqlcode != TX_SQL_OK) {
        TX_DBIO_LOG_ERR("SELECT st_ledger diff");
        tx_return(ctx, TX_EDB, ctx->out);
        return;
    }

    expected = st_fee_round(h_amount, std_bp);
    diff     = h_fee - expected;
    mismatch = ((diff < 0 ? -diff : diff) > tol);

    tx_buf_reset(ctx->out);
    tx_buf_sets(ctx->out, "RESPCODE", mismatch ? RESP_INVALID : RESP_OK);
    tx_buf_sets(ctx->out, "KEY", key);
    tx_buf_setlong(ctx->out, "AMOUNT", h_amount);
    tx_buf_setlong(ctx->out, "EXPECTED", expected);
    tx_buf_setlong(ctx->out, "ACTUAL", h_fee);
    tx_buf_setlong(ctx->out, "DIFF", diff);
    tx_buf_sets(ctx->out, "VERDICT", mismatch ? "MISMATCH" : "OK");
    tx_log(TX_LOG_INFO, "[ST_OL_0019] diff key=%s 예상=%ld 실제=%ld diff=%ld %s",
           key, expected, h_fee, diff, mismatch ? "불일치" : "일치");
    tx_return(ctx, mismatch ? TX_FAIL : TX_OK, ctx->out);
}