#include <iostream.h>
#include <fstream.h>     // for ifstream
#include <stdlib.h>      // for exit
#include "CPstring.h"
#include "uvmap.h"
#include "hmap.h"
#include "bstmap.h"
#include "ctimer.h"
#include "iterator.h"


// the mapstats class tracks how many
// different words there are, how many total words
// and what the average word length is

class MapStats : public MapBase<string,int>
{
  public:
    MapStats();
    virtual void function(string & key, int & value);
    virtual void report();

    int getTotal() const
    {
	return myTotal;
    }

  private:
    int myUnique;    // # different words
    int myTotal;     // total # words
    int myLengths;   // sum of all word lengths
};

MapStats::MapStats()
   : myUnique(0),
     myTotal(0),
     myLengths(0)
{
    // all done in initializer list
}

void MapStats::function(string & key, int & value)
{
    myUnique++;
    myTotal += value;
    myLengths += key.length() * value;
}

void MapStats::report()
{
    cout << "number of unique words = " << myUnique << endl;
    cout << "number of total words  = " << myTotal << endl;
    cout << "average word length = " 
	 << static_cast<double>(myLengths)/myTotal << endl;
}


void Print(Pair<string,int> & p)
{
    cout << p.second << "\t" << p.first << endl;
}

void ProcessWords(istream & input,Map<string,int> & map)
// postcondition: all words from input read, stored in map with count
//                of occurrences    
{
    string word;
    input.seekg(0);
    input.clear();             // clear for reading

    while (input >> word)
    {
	word = word.Downcase();
	if (! map.includes(word))    // word not stored in map
	{
	    map.insert(word,1);         // insert with one occurrence
	}
	else
	{
	    map.getValue(word) += 1;    // bump # occurrneces by 1
	}
    }

    // uncomment line below to print all entries in table
    map.apply(Print);

    return;
    
    MapStats stats;
    map.apply(stats);
    stats.report();

    cout << "frequent words (greater than 2%)" << endl;

    int total = stats.getTotal();
    
    Iterator<Pair<string,int> > * iter = map.makeIterator();
    
    for(iter->first(); ! iter->isDone(); iter->next())
    {
	if (iter->current().second > 0.02 *total)
	{
	    cout << iter->current().second << "\t"
		 << iter->current().first << endl;
	}
    }
}


unsigned int Hash(const string & s)
// postcondition: returns hash value for s (from Weiss)
{
    unsigned int hval = 0;
    int k;
    int len = s.length();
    for(k=0; k < len; k++)
    {
	hval = (hval << 5) ^ hval ^ s[k];
    }
    return hval;
}

int main()
{
    HMap<string,int> hmap(Hash,7001);
    BSTMap<string,int> bstmap;
    UVMap<string,int> uvmap(1000);
    
    string filename;
    ifstream input;

    cout << "file name: ";
    cin >> filename;

    input.open(filename.c_str());
    if (input.fail())
    {
	cerr << "could not open file " << filename << endl;
	exit(1);
    }

    CTimer timer;

    timer.Start();
    ProcessWords(input,hmap);    
    timer.Stop();
    cout << timer.ElapsedTime() << " seconds hash" << endl;


    input.close();
    input.open(filename.c_str());
    
    timer.Start();
    ProcessWords(input,bstmap);    
    timer.Stop();
    cout << timer.ElapsedTime() << " seconds bst" << endl;


    input.close();
    input.open(filename.c_str());
    
    timer.Start();
    ProcessWords(input,uvmap);    
    timer.Stop();
    cout << timer.ElapsedTime() << " seconds uvmap" << endl;
}