/* @tier medium @module mg @transform msg-gateway-online */
/*
 * mg_ol_0010.pgc - 전문 압축/해제 서비스 (MG_OL_0010)  [tier=medium]
 *
 * RAWMSG 를 RLE(Run-Length Encoding) 유사 방식으로 압축하여 압축길이/
 * 압축비를 산출한다. 압축결과를 다시 해제하여 원본과 일치하는지 검증
 * (round-trip)하고 압축통계와 검증결과를 응답한다. 순수 로직.
 */
#include <stdio.h>
#include <string.h>

#include "txcore.h"
#include "acq_util.h"
#include "mg_core.h"

EXEC SQL INCLUDE sqlca;

#define MG10_MAXRUN 255

TX_SERVICE(MG_OL_0010, ctx)
{
    char raw[256];
    unsigned char comp[512];
    char verify[256];
    int  rawlen, complen, vlen;
    int  i, j;
    long ratio;

    tx_log(TX_LOG_INFO, "[MG_OL_0010] 전문 압축/해제 서비스 진입");

    /* 1) 원문 수신 */
    if (tx_buf_get(ctx->in, "RAWMSG", raw, sizeof(raw)) != TX_OK) {
        tx_log(TX_LOG_ERROR, "[MG_OL_0010] 원문(RAWMSG) 누락");
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }
    rawlen = (int)strlen(raw);
    if (rawlen <= 0) {
        tx_log(TX_LOG_WARN, "[MG_OL_0010] 압축 대상 길이 0");
        tx_return(ctx, TX_EINVAL, ctx->out);
        return;
    }

    /* 2) RLE 압축: (반복횟수, 문자) 쌍 스트림 생성 */
    complen = 0;
    i = 0;
    while (i < rawlen) {
        int run = 1;
        while (i + run < rawlen && raw[i + run] == raw[i] && run < MG10_MAXRUN)
            run++;
        if (complen + 2 > (int)sizeof(comp)) {
            tx_log(TX_LOG_ERROR, "[MG_OL_0010] 압축버퍼 초과 complen=%d", complen);
            tx_return(ctx, TX_ENOMEM, ctx->out);
            return;
        }
        comp[complen++] = (unsigned char)run;
        comp[complen++] = (unsigned char)raw[i];
        i += run;
    }

    /* 3) 해제(round-trip) 검증 */
    vlen = 0;
    for (j = 0; j + 1 < complen; j += 2) {
        int cnt = comp[j];
        int k;
        for (k = 0; k < cnt && vlen < (int)sizeof(verify) - 1; k++)
            verify[vlen++] = (char)comp[j + 1];
    }
    verify[vlen] = '\0';

    if (vlen != rawlen || memcmp(verify, raw, rawlen) != 0) {
        tx_log(TX_LOG_ERROR, "[MG_OL_0010] round-trip 불일치 raw=%d vlen=%d", rawlen, vlen);
        tx_buf_reset(ctx->out);
        tx_buf_sets(ctx->out, "RESP", RESP_SYSERR);
        tx_buf_setlong(ctx->out, "VERIFY", 0);
        tx_return(ctx, TX_FAIL, ctx->out);
        return;
    }

    /* 4) 압축비(%) = 압축길이 * 100 / 원문길이 (낮을수록 효율적) */
    ratio = (long)complen * 100 / (long)rawlen;

    /* 5) 압축 통계 응답 */
    tx_buf_reset(ctx->out);
    tx_buf_sets(ctx->out, "RESP", RESP_OK);
    tx_buf_setlong(ctx->out, "RAWLEN", (long)rawlen);
    tx_buf_setlong(ctx->out, "COMPLEN", (long)complen);
    tx_buf_setlong(ctx->out, "RATIO", ratio);
    tx_buf_setlong(ctx->out, "VERIFY", 1);
    tx_log(TX_LOG_INFO, "[MG_OL_0010] 압축완료 raw=%d comp=%d ratio=%ld%%",
           rawlen, complen, ratio);
    tx_return(ctx, TX_OK, ctx->out);
}
