using namespace std;

/* Lots of Object Extras
Factories, Destructors, delete, Vector
Direct variable access, overriding operators

Third example - really showing much more that should be shown
in a single demo!
*/

#include <iostream>
#include <string>
#include <vector>

// Define the API to the class
// ---------------------------

class Activity {
        public:
                Activity(char *descriptor, float minutes, float cals);
                Activity(char *descriptor, float minutes, float cals, char *where);
                ~Activity();

                float getCalpm();
                char *getDesc();
                char *getLocation();
                Activity *moreEnergetic(Activity *that);
                Activity operator+(Activity that);

                static Activity *mostEnergetic(Activity *that[], int syze);
                static int getCount();

                // Factory Method - concept demo!

                static Activity *myFactory(char *descriptor,float minutes,float cpm);

                // Note - next is direct access to a variable (Yuk!)
                // (Yuk because we can't put code between value and
                // caller later on if we need to. Nailed not screwed!)
                float cals;

        private:
                float mins;
                char *description; // Option 1 - pointer
                char location[21]; // Option 2 - hold it here
                static int options_count;
};

Activity::Activity(char *description, float mins, float cals) {
        Activity::options_count++;
        this->mins = mins;
        this->cals = cals;
        this->description = description;
        *(this->location) = '\0';
        }

Activity::Activity(char *description, float mins, float cals, char *where) {
        Activity::options_count++;
        this->mins = mins;
        this->cals = cals;
        this->description = description;
        // we need to copy the string! ...
        strcpy(this->location,where);
        }

// Factory method
// Note
// - factories can also return arrays of objects
// - factories can choose to return objects of different derived types

Activity * Activity::myFactory(char *descriptor,float minutes,float cpm) {
        float totcal = minutes * cpm;
        return new Activity(descriptor, minutes, totcal);
        }

// Destructor - automatic for stack variables (heap - beware - use delete!)

Activity::~Activity() {
        cout << this->description << " completed" << endl;
        }

float Activity::getCalpm() {
        return cals / mins;
        }

char * Activity::getDesc() {
        return description;
        }

char * Activity::getLocation() {
        return location;
        }

Activity Activity::operator+(Activity that) {
        float length = this->mins + that.mins;
        float totcal = this->cals + that.cals;
        // Careful - do not return something that's
        // about to go out of scope and become garbage!
        return Activity("Combo",length,totcal,"Various");
        }

Activity * Activity::moreEnergetic(Activity *that) {
        // Call to internal methods to avoid problems with
        // inheritance - i.e. take advantage of Polly Morphism.
        if (this->getCalpm() < that->getCalpm()) return that;
        return this;
        }

Activity * Activity::mostEnergetic(Activity **that, int syze) {
        Activity *so_far = that[0];
        int k;
        for (k=1; k<syze; k++) {
                so_far = so_far->moreEnergetic(that[k]);
                }
        return so_far;
        }

int Activity::getCount() {
        return options_count;
        }

int Activity::options_count = 0;

// Main test program - what do want to be able to do with activities?
// ------------------------------------------------------------------

int main () {

        Activity * Weekend[4] ;
        int k;

        Weekend[0] = new Activity("Walk da dog",60.0,1000.0," in da field");
        Weekend[1] = new Activity("With Widdy",3.0,400.0);
        // Weekend[2] = new Activity("With Bruce",2.0,200.0);
        Weekend[3] = new Activity("Walk the goldfish",20.0,50.0,"pondelled");

        // Factory (little more than repackaging at the gate!)
        // Normally - would pass in a string with all the data from a file
        Weekend[2] = Activity::myFactory("With Brucella",2.0,100.0);

        for (k=0; k<4; k++) {
                Activity *Current = Weekend[k];
                cout << Current->getDesc() << " burns up " <<
                        Current->getCalpm() << " c.p.m at " <<
                        Current->getLocation() << endl;
        }
        cout << "Object count " << Activity::getCount() << endl ;

// Comparator - "more"

        Activity *MoreEnergy = Weekend[0]->moreEnergetic(Weekend[2]);
        cout << "more - " << MoreEnergy->getDesc() << endl;

// Comparator - "most"

        Activity *MostEnergy = Activity::mostEnergetic(Weekend,4);
        cout << "most - " << MostEnergy->getDesc() << endl;

// Overriding Operators

        Activity Saturday = *Weekend[1] + *Weekend[2];
        cout << Saturday.getDesc() << " burns up " <<
                Saturday.getCalpm() << " c.p.m at " <<
                Saturday.getLocation() << endl;

// Direct variable access

        cout << Saturday.cals << " Calories in total" << endl;

// Getting rid of the heap objects:

        for (k=0; k<4; k++) {
                delete Weekend[k];
        }

// And lets finish this one with a vector!
// Used if we don't know how many items there will be

        vector <Activity *> Todos(0);

        Todos.push_back(new Activity("eating",45.,-500.));
        Todos.push_back(new Activity("sleeping",300.,200.));
        Todos.push_back(new Activity("working",400.,1200.));

        for (k=0; k<Todos.size(); k++) {
                Activity * Current = Todos.at(k);
                cout << Current->getDesc() << " burns up " <<
                        Current->getCalpm() << " c.p.m at " <<
                        Current->getLocation() << endl;
        }

        return 0;
        }

/* Sample Run

wizard:cppcsr graham$ ./act_03
Walk da dog burns up 16.6667 c.p.m at in da field
With Widdy burns up 133.333 c.p.m at
With Brucella burns up 100 c.p.m at
Walk the goldfish burns up 2.5 c.p.m at pondelled
Object count 4
more - With Brucella
most - With Widdy
With Brucella completed
Combo burns up 120 c.p.m at Various
600 Calories in total
Walk da dog completed
With Widdy completed
With Brucella completed
Walk the goldfish completed
eating burns up -11.1111 c.p.m at
sleeping burns up 0.666667 c.p.m at
working burns up 3 c.p.m at
Combo completed
wizard:cppcsr graham$

*/