/* @tier easy @module lg @transform ledger-online */
/*
 * lg_ol_0021.pgc - 원장 온라인 서비스 (LG_OL_0021)  [tier=easy]
 *
 * 복식 전표생성: 하나의 거래에 대해 차변행(음수)과 대변행(양수) 두 행을
 * 한 트랜잭션으로 INSERT 하고, 두 행 금액 합(Σ=0) 균형검증 결과를 응답한다.
 */
#include <stdio.h>
#include <string.h>

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

EXEC SQL INCLUDE sqlca;

TX_SERVICE(LG_OL_0021, ctx)
{
    EXEC SQL BEGIN DECLARE SECTION;
    char h_key_dr[16];
    char h_key_cr[16];
    char h_merch_id[16];
    char h_biz_date[9];
    char h_status[2];
    long h_debit;
    long h_credit;
    EXEC SQL END DECLARE SECTION;

    char key[16], merch[16], bizdate[16];
    long amount = 0;
    long balance;

    tx_log(TX_LOG_INFO, "[LG_OL_0021] 복식 전표생성 진입");

    if (tx_buf_get(ctx->in, "KEY", key, sizeof(key)) != TX_OK ||
        tx_buf_get(ctx->in, "MERCHID", merch, sizeof(merch)) != TX_OK ||
        tx_buf_get(ctx->in, "BIZDATE", bizdate, sizeof(bizdate)) != TX_OK) {
        tx_log(TX_LOG_ERROR, "[LG_OL_0021] 필수 필드 누락");
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_INVALID);
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }
    tx_buf_getlong(ctx->in, "AMOUNT", &amount);

    if (!amount_is_valid(amount) || !date_is_valid(bizdate)) {
        tx_log(TX_LOG_WARN, "[LG_OL_0021] 입력 검증 실패 amount=%ld date=%s",
               amount, bizdate);
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_INVALID);
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }

    /* 차변/대변 처리키 파생 (원거래키 + 접미) */
    snprintf(h_key_dr, sizeof(h_key_dr), "%.13sDR", key);
    snprintf(h_key_cr, sizeof(h_key_cr), "%.13sCR", key);
    strncpy(h_merch_id, merch, sizeof(h_merch_id) - 1);
    h_merch_id[sizeof(h_merch_id) - 1] = '\0';
    strncpy(h_biz_date, bizdate, sizeof(h_biz_date) - 1);
    h_biz_date[sizeof(h_biz_date) - 1] = '\0';
    strncpy(h_status, LG_ST_RECV, sizeof(h_status) - 1);
    h_status[sizeof(h_status) - 1] = '\0';
    h_debit  = -amount;   /* 차변: 음수 */
    h_credit =  amount;   /* 대변: 양수 */

    if (tx_begin() != TX_OK) {
        tx_return(ctx, TX_FAIL, ctx->out);
        return;
    }

    EXEC SQL INSERT INTO lg_ledger
        (key, merch_id, card_no, amount, biz_date, status, fee)
        VALUES
        (:h_key_dr, :h_merch_id, '', :h_debit, :h_biz_date, :h_status, 0);
    if (sqlca.sqlcode != TX_SQL_OK) {
        TX_DBIO_LOG_ERR("lg_ol_0021 debit insert");
        tx_abort();
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_SYSERR);
        tx_return(ctx, TX_EDB, ctx->out);
        return;
    }

    EXEC SQL INSERT INTO lg_ledger
        (key, merch_id, card_no, amount, biz_date, status, fee)
        VALUES
        (:h_key_cr, :h_merch_id, '', :h_credit, :h_biz_date, :h_status, 0);
    if (sqlca.sqlcode != TX_SQL_OK) {
        TX_DBIO_LOG_ERR("lg_ol_0021 credit insert");
        tx_abort();
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_SYSERR);
        tx_return(ctx, TX_EDB, ctx->out);
        return;
    }

    /* 복식부기 균형검증: 차변 + 대변 = 0 */
    balance = h_debit + h_credit;
    if (balance != 0) {
        tx_log(TX_LOG_ERROR, "[LG_OL_0021] 균형검증 실패 balance=%ld", balance);
        tx_abort();
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESPCODE", RESP_SYSERR);
        tx_return(ctx, TX_FAIL, ctx->out);
        return;
    }

    if (tx_commit() != TX_OK) {
        tx_abort();
        tx_return(ctx, TX_FAIL, ctx->out);
        return;
    }

    tx_buf_reset(ctx->out);
    tx_buf_sets(ctx->out, "RESPCODE", RESP_OK);
    tx_buf_sets(ctx->out, "KEYDR", h_key_dr);
    tx_buf_sets(ctx->out, "KEYCR", h_key_cr);
    tx_buf_setlong(ctx->out, "DEBIT", h_debit);
    tx_buf_setlong(ctx->out, "CREDIT", h_credit);
    tx_buf_setlong(ctx->out, "BALANCE", balance);
    tx_log(TX_LOG_INFO, "[LG_OL_0021] 복식전표 생성완료 key=%s 균형=%ld", key, balance);
    tx_return(ctx, TX_OK, ctx->out);
}