/* @tier medium @module au @transform authorization-online */
/*
 * au_ol_0004.pgc - 승인 한도차감(UPDATE 잔액 감액) (AU_OL_0004)  [tier=medium]
 *
 * TxCore TX_SERVICE 엔트리. 요청 TXBUF 를 검증하고 임베디드 SQL / 표준
 * DBIO / tx_call 로 처리한 뒤 응답 TXBUF 를 구성한다.
 */
#include <stdio.h>
#include <string.h>

#include "txcore.h"
#include "txcore_dbio.h"
#include "acq_util.h"
#include "au_core.h"

EXEC SQL INCLUDE sqlca;

TX_SERVICE(AU_OL_0004, ctx)
{
    char key[16];
    if (tx_buf_get(ctx->in, "KEY", key, sizeof(key)) != TX_OK) {
        tx_log(TX_LOG_ERROR, "[AU_OL_0004] KEY 누락");
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }
    EXEC SQL BEGIN DECLARE SECTION;
    char h_key[16], h_status[2];
    long h_amount, h_bal;
    EXEC SQL END DECLARE SECTION;

    long amount = 0;

    tx_log(TX_LOG_INFO, "[AU_OL_0004] 승인 한도차감 진입");
    tx_buf_getlong(ctx->in, "AMOUNT", &amount);
    if (!amount_is_valid(amount)) {
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }

    strncpy(h_key, key, 15); h_key[15] = '\0';
    h_amount = amount;

    EXEC SQL SELECT amount, status INTO :h_bal, :h_status
        FROM au_ledger WHERE key = :h_key;
    if (sqlca.sqlcode == TX_SQL_NOTFOUND) {
        tx_return(ctx, TX_ENOENT, ctx->out);
        return;
    }
    if (h_bal < h_amount) {
        tx_log(TX_LOG_WARN, "[AU_OL_0004] 한도부족 bal=%ld req=%ld", h_bal, h_amount);
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_INVALID);
        tx_return(ctx, TX_FAIL, ctx->out);
        return;
    }

    if (tx_begin() != TX_OK) tx_log(TX_LOG_WARN, "[AU_OL_0004] tx_begin 경고");
    EXEC SQL UPDATE au_ledger
        SET amount = amount - :h_amount, upd_ts = now()
        WHERE key = :h_key AND status = 'R';
    if (sqlca.sqlcode != TX_SQL_OK || sqlca.sqlerrd[2] == 0) {
        TX_DBIO_LOG_ERR("au_ol_0004 차감");
        tx_abort();
        tx_return(ctx, TX_EDB, ctx->out);
        return;
    }
    EXEC SQL SELECT amount INTO :h_bal FROM au_ledger WHERE key = :h_key;
    tx_commit();

    tx_buf_reset(ctx->out);
    tx_buf_sets(ctx->out, "RESPCODE", RESP_OK);
    tx_buf_setlong(ctx->out, "REMAIN", h_bal);
    tx_log(TX_LOG_INFO, "[AU_OL_0004] 차감완료 잔액=%ld", h_bal);
    tx_return(ctx, TX_OK, ctx->out);
}