/*-----------------------------------------------------------------------
  Implementation file for the SICS help system.

  copyright: see file COPYRIGHT

  Mark Koennecke, December 2003
-----------------------------------------------------------------------*/
#include <stdio.h>
#include <assert.h>
#include <errno.h>
#include "fortify.h"
#include "sics.h"
#include "help.h"

extern char *stptok(const char *s, char *tok, size_t toklen, char *brk);

/*----------------------------------------------------------------------*/
#define PATHSEP ":"
#define DIRSEP "/"
static char *helpDirs = NULL;
static char *defaultFile="master.txt";
/*----------------------------------------------------------------------*/
void KillHelp(void *pData){
  KillDummy(pData);
  if(helpDirs != NULL){
    free(helpDirs);
    helpDirs = NULL;
  }
}
/*-----------------------------------------------------------------------*/
static FILE *findHelpFile(char *name){
  FILE *fd = NULL;
  char pBueffel[256];
  char dir[132];
  char *pPtr;

  if(helpDirs == NULL){
    return NULL;
  }

  pPtr = helpDirs;
  while( (pPtr = stptok(pPtr,dir,131,PATHSEP)) != NULL){
    strcpy(pBueffel,dir);
    strcat(pBueffel,DIRSEP);
    strncat(pBueffel,name,(254-strlen(pBueffel)));
    fd = fopen(pBueffel,"r");
    if(fd != NULL){
      return fd;
    }
  }
  
  /*
    this means: not found!
  */
  return NULL;
}
/*----------------------------------------------------------------------*/
static void printHelpFile(SConnection *pCon, FILE *fd){
  char line[132];

  while(fgets(line,131,fd) != NULL){
    SCWrite(pCon,line,eValue);
  }
}
/*----------------------------------------------------------------------*/
static void configureHelp(SConnection *pCon,
			  char *option, char *parameter){
  char *pPtr = NULL;
  int length;

  strtolower(option);
  if(strcmp(option,"adddir") == 0){
    if(parameter == NULL){
      SCWrite(pCon,helpDirs,eValue);
      return;
    } else {
      pPtr = helpDirs;
      if(pPtr != NULL){
	length = strlen(pPtr) + strlen(PATHSEP) + strlen(parameter) + 2;
	helpDirs = (char *)malloc(length*sizeof(char));
	memset(helpDirs,0,length*sizeof(char));
	strcpy(helpDirs,pPtr);
	strcat(helpDirs,PATHSEP);
	strcat(helpDirs,parameter);
	free(pPtr);
      } else {
	helpDirs=strdup(parameter);
      }
    }
  } else if(strcmp(option,"defaultfile") == 0){
    if(parameter == NULL){
      SCWrite(pCon,defaultFile,eValue);
      return;
    } else {
      if(defaultFile != NULL){
	free(defaultFile);
      }
      defaultFile = strdup(parameter);
    }
  } else {
    SCWrite(pCon,"Unknown option to configure",eWarning);
    SCWrite(pCon,"Known options: defaultfile, adddir",eWarning);
  }
}
/*-----------------------------------------------------------------------*/
int SicsHelp(SConnection *pCon,SicsInterp *pSics, void *pData, 
	     int argc, char *argv[]){
  char helpFile[256];
  FILE *fd = NULL;

  strncpy(helpFile,defaultFile,255);

  if(argc > 1){
    strtolower(argv[1]);
    /*
      check for configure
    */
    if(strcmp(argv[1],"configure") == 0){
      if(argc < 3){
	SCWrite(pCon,"ERROR: need an option to configure",eError);
	return 0;
      }
      if(argc > 3){
	configureHelp(pCon,argv[2],argv[3]);
      } else {
	configureHelp(pCon,argv[2],NULL);
      }
      SCSendOK(pCon);
      return 1;
    }
    /*
      the parameter is a help file name
    */
    strncpy(helpFile,argv[1],255);
    strncat(helpFile,".txt",255);
  }

  /*
    print the helpFile
  */
  fd = findHelpFile(helpFile);
  if(fd == NULL){
    SCWrite(pCon,"ERROR: failed to locate helpFile:",eError);
    SCWrite(pCon,helpFile,eError);
    return 0;
  }
  printHelpFile(pCon,fd);
  fclose(fd);
  return 1;
}