/*
** 2025-10-20
**
** The author disclaims copyright to this source code.  In place of
** a legal notice, here is a blessing:
**
**    May you do good and not evil.
**    May you find forgiveness for yourself and forgive others.
**    May you share freely, never taking more than you give.
**
*************************************************************************
** A simple command-line program for testing the Result-Format or "resfmt"
** utility library for SQLite.
*/
#include <stdio.h>
#include <string.h>
#include "sqlite3.h"
#include "resfmt.h"

/* Report out-of-memory and die if the argument is NULL */
static void checkOOM(void *p){
  if( p==0 ){
    fprintf(stdout, "out-of-memory\n");
    exit(1);
  }
}

/* A block of memory */
typedef struct memblock memblock;
struct memblock {
  memblock *pNext;
};

/* List of all memory to be freed */
static memblock *pToFree = 0;

/* Free all memory at exit */
static void tempFreeAll(void){
  while( pToFree ){
    memblock *pNext = pToFree->pNext;
    sqlite3_free(pToFree);
    pToFree = pNext;
  }
}

/* Allocate memory that will be freed all at once by freeall() */
static void *tempMalloc(unsigned n){
  memblock *p;
  if( n>0x10000000 ) checkOOM(0);
  p = sqlite3_malloc64( n+sizeof(memblock) );
  checkOOM(p);
  p->pNext = pToFree;
  pToFree = p;
  return (void*)&pToFree[1];
}

/* Function used for writing to the console */
ssize_t testWriter(void *pContext, const unsigned char *p, size_t n){
  return fwrite(p,1,n,stdout);
}

int main(int argc, char **argv){
  char *zSrc;
  FILE *pSrc;
  sqlite3_str *pBuf;
  sqlite3 *db = 0;
  sqlite3_stmt *pStmt;
  int rc;
  int lineNum = 0;
  sqlite3_resfmt_spec spec;
  char zLine[1000];

  if( argc<2 ){
    zSrc = "<stdin>";
    pSrc = stdin;
  }else{
    zSrc = argv[1];
    pSrc = fopen(zSrc, "rb");
    if( pSrc==0 ){
      fprintf(stderr, "cannot open \"%s\" for reading\n", zSrc);
      exit(1);
    }
  }
  memset(&spec, 0, sizeof(spec));
  spec.iVersion = 1;
  spec.eFormat = RESFMT_Line;
  spec.xWrite = testWriter;
  pBuf = sqlite3_str_new(0);
  while( fgets(zLine, sizeof(zLine), pSrc) ){
    size_t n = strlen(zLine);
    lineNum++;
    while( n>0 && zLine[n-1]>0 && zLine[n-1]<=' ' ) n--;
    zLine[n] = 0;
    printf("%s\n", zLine);
    if( strncmp(zLine, "--open=", 7)==0 ){
      if( db ) sqlite3_close(db);
      db = 0;
      rc = sqlite3_open(&zLine[7], &db);
      if( rc!=SQLITE_OK ){
        fprintf(stderr, "%s:%d: cannot open \"%s\": %s\n",
                zSrc, lineNum, &zLine[7],
                sqlite3_errmsg(db));
        exit(1);
      }
    }else
    if( strcmp(zLine, "--go")==0 ){
      char *zSql;
      sqlite3_resfmt *pFmt;
      int iErr = 0;
      char *zErr = 0;
      if( db==0 ){
        fprintf(stderr, "%s:%d: database not open\n", zSrc, lineNum);
        exit(1);
      }
      zSql = sqlite3_str_value(pBuf);
      pStmt = 0;
      rc = sqlite3_prepare_v2(db, zSql, -1, &pStmt, 0);
      if( rc || pStmt==0 ){
        fprintf(stderr, "%s:%d: sqlite3_prepare() fails: %s\n",
                zSrc, lineNum, sqlite3_errmsg(db));
      }
      pFmt = sqlite3_resfmt_begin(pStmt, &spec);
      while( sqlite3_step(pStmt)==SQLITE_ROW ){
        sqlite3_resfmt_row(pFmt);
      }
      rc = sqlite3_resfmt_finish(pFmt, &iErr, &zErr);
      printf("rc=%d.  error-code=%d.  error-message=%s\n",
             rc, iErr, zErr ? zErr : "NULL");
      sqlite3_free(zErr);
      sqlite3_finalize(pStmt);
      pStmt = 0;
      sqlite3_str_reset(pBuf);
    }else
    if( strcmp(zLine, "--exit")==0 ){
      break;
    }else
    {
      if( sqlite3_str_length(pBuf) ) sqlite3_str_appendchar(pBuf, ' ', 1);
      sqlite3_str_appendall(pBuf, zLine);
    }
  }
  if( db ) sqlite3_close(db);
  sqlite3_free(sqlite3_str_finish(pBuf));
  tempFreeAll();
  if( pSrc!=stdin ) fclose(pSrc);
  return 0;
}