/**********************************************************************
 *
 * historydb.cpp -- 
 * Copyright (C) 1999  The New Zealand Digital Library Project
 *
 * A component of the Greenstone digital library software
 * from the New Zealand Digital Library Project at the
 * University of Waikato, New Zealand.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *********************************************************************/

#include "historydb.h"
#include "fileutil.h"
#include "cgiutils.h"
#include "recptproto.h"
#include "OIDtools.h"


// returns true on success (in which case historyinfo will contain
// the information for this history)
bool get_history_info (const text_t &userid, text_tarray &historyinfo, 
		       const text_t &gsdlhome, ostream &logout) {

  text_t historyfile = filename_cat(gsdlhome, "etc", "history.db");
  
  bool result = false;
  // open the history database  
  gdbmclass historydb;
  
  if (historydb.opendatabase(historyfile, GDBM_READER, 1000, true)) {
    // get history list
    text_t historyresult;
    
    historydb.getkeydata(userid, historyresult);
    
    if (historyresult != "") { //  there are entries, process them
      
      splitchar(historyresult.begin(), historyresult.end(), '\n', historyinfo);
      result = true;
    }
    historydb.closedatabase();
    
  } else {
    outconvertclass text_t2ascii;
    logout << text_t2ascii << "couldn't open history database " << historyfile << "\n";
  }
  return result;
}


// returns true on success
bool set_history_info (const text_t &userid, const text_t &history, const text_t &gsdlhome) {

  text_t historyfile = filename_cat(gsdlhome, "etc", "history.db");
  
  bool result = false;
  // open the history database  
  gdbmclass historydb;
  
  text_t querynum;
  text_t historyresult;

  
  if ( !historydb.opendatabase(historyfile, GDBM_READER, 1000, true)) {
    // not created yet
    historyresult="";
    querynum="1";
  }
  else {

    // get history list
   if (! historydb.getkeydata(userid, historyresult)) {
     historyresult="";
     querynum="1";
   }
   historydb.closedatabase();
  }

  // get next query num
  if (historyresult!="") {
    text_tarray entries;
    splitchar(historyresult.begin(), historyresult.end(), '\n', entries);
    get_query_num(entries.back(), querynum);
    querynum.setint(querynum.getint()+1);
  }
  
  // open for writing
  if (!historydb.opendatabase(historyfile, GDBM_WRCREAT, 1000, true)) return false;
    
  // add on new line
  historyresult += querynum;
  historyresult += ":";
  historyresult += history;
  historyresult += "\n";
  
    if (historydb.setinfo(userid, historyresult)) 
      result=true; 
    
    historydb.closedatabase();
    return result;
}

// deletes all a users history
bool delete_all_history_info (const text_t &userid, const text_t &gsdlhome) {

  text_t historyfile = filename_cat(gsdlhome, "etc", "history.db");
  
  // open the history database  
  gdbmclass historydb;
  
  if ( !historydb.opendatabase(historyfile, GDBM_WRITER, 1000, true)) return false;

  historydb.deletekey(userid);
  historydb.closedatabase();
  return true;
  
}

//deletes only the selected records
bool delete_history_info (const text_t &userid, const text_t &deletemode, 
			  const text_t &selection, const text_t &gsdlhome) {

  text_t historyfile = filename_cat(gsdlhome, "etc", "history.db");
  bool result = false;
  // open the history database  
  gdbmclass historydb;
  
  if ( !historydb.opendatabase(historyfile, GDBM_READER, 1000, true)) return false;

  // get history list
  text_t historyresult;

  if (! historydb.getkeydata(userid, historyresult)) return false;
   
  historydb.closedatabase();

  text_t newhistory; // for the new list of search history
  // get list of queries
  text_tarray queries;
  splitchar(historyresult.begin(), historyresult.end(), '\n', queries);
  text_tarray::iterator begin=queries.begin();
  text_tarray::iterator end=queries.end();
  
  // get list of numbers to delete
  text_tarray numbers;
  splitchar(selection.begin(), selection.end(), ',', numbers);
  text_tarray::iterator numbegin=numbers.begin();
  text_tarray::iterator numend=numbers.end();

  bool tdefault, tset;
  if (deletemode=="delete") {
    tdefault=true;
    tset=false;
  }
  else {// deletemode == save
    tdefault=false;
    tset=true;
  }

  // create a HistRecord map of all the entries
  HistRecordmap records;
  while (begin != end) {
    HistRecord rec;
    rec.entry=*begin;
    rec.save=tdefault;
    text_t num;
    get_query_num(*begin, num);
    records[num] = rec;
    begin++;
  }

 
  // now set the save field for all records that are selected
  while(numbegin != numend) {
    
    if (is_number(*numbegin)) {
      if (records.count(*numbegin)==1) {
	records[*numbegin].save=tset;
      } // else invalid number
    }
    else{
      int start, stop;
      if (get_selection_params(*numbegin, start, stop)) {
	for (int i=start; i<=stop; i++) {
	  text_t num = i;
	  if (records.count(num)==1) {
	    records[num].save=tset;
	  }
	}}
	else { // dodgy format 
	  // error message
	}
      
    }
    numbegin++;
  } // while
	
  HistRecordmap::iterator recbegin = records.begin();
  HistRecordmap::iterator recend = records.end();
 
  //create new history record - go through all Records
  // and add to new history those with save set to true
  while (recbegin != recend) {
    if ((*recbegin).second.save) {
      expand_query((*recbegin).second, records);
      newhistory += (*recbegin).second.entry + "\n";
    }
    recbegin++;
  }
  
  // open for writing
  if (!historydb.opendatabase(historyfile, GDBM_WRITER, 1000, true)) return false;
  
  if (historydb.setinfo(userid, newhistory)) result = true; 
  
  historydb.closedatabase();
  return result;
}

bool get_selection_params (text_t &data, int &start, int &stop) {
  
  text_tarray results;
  
  splitchar(data.begin(), data.end(), '-', results);
  if (results.size()==2 && is_number(results[0]) && is_number(results[1])) {
    start=results[0].getint();
    stop=results[1].getint();
    return true;
  }
  
  // error message
  return false;
}

// expand query takes a HistRecord, and expands out any hashes in
// the query string for queries that aren't to be saved
bool expand_query(HistRecord &record,  HistRecordmap &records) {

  text_tarray args;
  splitchar(record.entry.begin(), record.entry.end(), '&', args);

  text_tarray::iterator begin=args.begin();
  text_tarray::iterator end=args.end();

  text_t query;
  // find the q argument
  while(begin != end) {
    if ((*begin)[0] == 'q'&& (*begin)[1] == '=') {
      query=*begin;
      args.erase(begin);
      break;
    } else begin++;
  }
  if (query !="") {
    
    //remove the q=
    text_t::iterator front = query.begin();
    query.erase(front);
    front=query.begin();
    
    query.erase(front);
    decode_cgi_arg(query);
    // now have just the query string
    // check any refs in it to see if they are still valid
    combine_query(query, records);
    text_t formattedquery = cgi_safe(query);
    text_t newquery = "q=";
    newquery += formattedquery;

    args.push_back(newquery);
    joinchar(args, '&', record.entry); 
    
    return true;
  } 
  return false;
}

// replaces a reference to a previous query with the search
// string from that query
bool combine_query(text_t &userid, text_t &query, const text_t &gsdlhome) 
{
  text_t::iterator begin = query.begin();
  text_t::iterator end = query.end();
  text_t::iterator it = findchar(begin, end, '#');
  if (it==end) return true;  // no need to swap anything
   
 
  text_t queryresult = "";
  text_t historyfile = filename_cat(gsdlhome, "etc", "history.db");
  text_t historyresult;
  // open the history database  
  gdbmclass historydb;
  bool exists = false;
  if (historydb.opendatabase(historyfile, GDBM_READER, 1000, true)) {
    // get history list
    if (historydb.getkeydata(userid, historyresult)) {
      exists=true;
      
      historydb.closedatabase();
    }
  }
  if (!exists) {// cant open history file, or user entry doesn't exist. replace #x with blanks 
    while(it !=end) {
      queryresult += substr(begin, it);
      it++;
      while(*it>='0'&&*it<='9') it++;
      begin=it;
      it=findchar(begin, end, '#');
    }
    queryresult += substr(begin, end);
    query = queryresult;
    return false;
  }
  bool result=true;

  // if have got to here, have a previous history in historyresult
  text_tarray historyinfo;
  splitchar(historyresult.begin(), historyresult.end(), '\n', historyinfo);
  text_tarray::iterator histbegin = historyinfo.begin();
  text_tarray::iterator histend = historyinfo.end();
  
  text_tmap historymap;
  // put all entries into a map, so can pull out the appropriate one easily
  while (histbegin != histend) {
    text_t num;
    get_query_num(*histbegin, num);
    historymap[num]=*histbegin;
    histbegin++;
  }
  while(it!=end) { // while there still is a hash present
    text_t querynum;
    text_t newquery;
    
    while (begin!=end) {
      if (*begin==text_t('#')) {
	begin++;
	while(begin !=end && *begin>='0'&&*begin<='9') {
	  querynum.push_back(*begin);
	  begin++;
	}
        text_t oldquery = historymap[querynum];
	if (oldquery !="") {   // valid entry
	  parse_saved_args(oldquery, "q", newquery);
	  decode_cgi_arg(newquery);
	  queryresult += newquery;
	}
	else {
	  result=false;
	}
	querynum.clear();
        // else do nothing (replace #x with nothing)
      } // if
      else {
	queryresult.push_back(*begin);
	begin++;
      }
    } // while begin!=end
    
    // have got to end of query string, 
    // now go back and check for internal #
    query = queryresult;
    begin = query.begin();
    end = query.end();
    it = findchar(begin, end, '#');
    queryresult.clear();
    
  } // while it !=end
  
  
  return result;
  
} // combine query


// replaces a reference to a previous query with the search
// string from that query, uses the Histrecordmap rather than the GDBM file
bool combine_query( text_t &query, HistRecordmap &records) 
{
  text_t::iterator begin = query.begin();
  text_t::iterator end = query.end();
  text_t::iterator it = findchar(begin, end, '#');
  if (it==end) return true;  // no need to swap anything
    
  text_t queryresult = "";
  bool changed=true;
  while(it!=end && changed) { // while there still is a hash present
                              // and query has changed since last time round
                              // we are leaving some #X in 
    text_t querynum;
    text_t newquery;
    changed=false;
    while (begin!=end) { // go through the query looking for hash
      if (*begin==text_t('#')) {
	begin++;
	while(begin !=end && *begin>='0'&&*begin<='9') {
	  querynum.push_back(*begin);
	  begin++;
	}
	if(records.count(querynum)>0) { // valid entry
	  if (!records[querynum].save){ // referenced record to be deleted
	    // get the q arg out of referenced query
	    parse_saved_args(records[querynum].entry, "q", newquery);
	    decode_cgi_arg(newquery);
	    queryresult += newquery;
	    changed=true;
	  }
	  else { // leave the #x in
	   queryresult.push_back('#');
	   queryresult +=  querynum;
	  }
	}
	querynum.clear();
	newquery.clear();
	// else do nothing (replace #x with nothing)
      } // if its a hash
      else {
	queryresult.push_back(*begin);
	begin++;
      }
    } // while begin!=end
    
    // have got to end of query string, 
    // now go back and check for internal #
    query = queryresult;
    begin = query.begin();
    end = query.end();
    it = findchar(begin, end, '#');
    queryresult.clear();
    
  } // while it !=end
  
  return true;
} // combine query

// retrieves the value of one of the arguments
void parse_saved_args(text_t &args, text_t key, text_t &value)
{
  text_t::iterator here = args.begin();
  text_t::iterator end = args.end();
  text_t::iterator it;
  while (here != end) {
    if(*here==key[0]) {
      it=findchar(here, end, '=');
      if (it==end) {
	value=""; return;
      }
      text_t entry = substr(here, it);
      if (entry==key) {
	here=it+1;
      	it=findchar(here, end, '&');
	value = substr(here, it);
	return;
      }
    }
    here++;
  }// while
}

// retrieves the value of all of the arguments
void parse_saved_args(text_t &args, infodbclass &info)
{
  text_t::iterator here = args.begin();
  text_t::iterator end = args.end();
  text_t::iterator it;
  text_tarray values;

  splitchar(here, end, '&', values);
  
  text_tarray::iterator start = values.begin();
  text_tarray::iterator stop = values.end();

  text_t key;
  text_t value;
  while(start!=stop) {

    here=(*start).begin();
    end=(*start).end();
    it=findchar(here, end, '=');
    if (it!=end) {
      key = substr(here, it);
      value = substr(it+1, end);
      
      info[key]=value;
    }
    start++;
  }
}

void get_query_num(text_t &query, text_t &querynum)
{
  text_t::iterator begin = query.begin();

  while (*begin >='0'&& *begin <='9') { // get the digits
    querynum.push_back(*begin);
    begin++;
  }
  if (*begin != ':') {
    // something has gone wrong
  }   
}

void split_saved_query(text_t &query, text_t &querynum, text_t &numdocs, text_t &cgiargs)
{
  text_t::iterator begin = query.begin();
  text_t::iterator end = query.end();
  
  while (*begin >='0'&& *begin <='9') { // get the digits
    querynum.push_back(*begin);
    begin++;
  }
  if (*begin != ':') {
    // something has gone wrong
  }
  else begin++;
  while (*begin >='0'&& *begin <='9') { // get the digits
    numdocs.push_back(*begin);
    begin++;
  }                                                                                                                         
  if (*begin == '+') {  // get the + if there
    numdocs.push_back(*begin);
    begin++;
  }

  cgiargs += (substr(begin, end));  // put rest of query into cgiargs

}

void format_user_info (text_t &cgiargs, text_t &userinfo,  recptprotolistclass *protos, ostream &logout) 
{
  logout << "in format user info";
  text_tset metadata;
  
  infodbclass argsinfo;
  parse_saved_args(cgiargs, argsinfo);
  
  text_t collect = argsinfo["c"];
  if (collect=="") {
    userinfo="";
    return;
  }
  recptproto *collectproto = protos->getrecptproto(collect,logout);
  if (collectproto == NULL) {
    userinfo="";
    return;
  }
  metadata.insert(argsinfo["h"]);
  FilterResponse_t response;

  get_info("collection", collect, metadata, false, collectproto, response, logout);

  text_t index = response.docInfo[0].metadata[argsinfo["h"]].values[0];
  
  text_t mode;
  if (argsinfo["b"]=="0") { // simple mode
    if (argsinfo["t"]=="0") {
      mode = "all words";
    }
    else { // t=1
      mode = "some words";
    }
    
  } 
  else { // advanced mode
    if (argsinfo["t"]=="0") {
      mode = "boolean";
    }
    else {
      mode = "ranked";
    }
  }
  
  text_t options;
  if (argsinfo["k"]=="0") {
    options = "case must match";
  }
  else {
    options = "ignore case";
  }
  if (argsinfo["s"]=="0") {
    options += ", whole word must match";
  }
  else {
    options += ", ignore word endings";
  }
  
  userinfo.clear();
  userinfo = "collection ("+argsinfo["c"] + ") ";
  userinfo += "search (" + index + ") ";
  userinfo += "mode (" + mode +") ";
  userinfo += "options (" + options + ")";

  logout << "in format user info - end";
}