#include "Catalog.h"
#include <cassert>
#include <sstream>
using std::istringstream;
using std::getline;

const char* STUDENTS_FILE = "students.data";
const char* ITEMS_FILE = "items.data";
const char* COMMANDS_FILE = "commands.data";
const char* OUTPUT_FILE = "output.data";

Catalog::Catalog() : out(OUTPUT_FILE) {
    // Make sure the output file opened
    assert (!out.fail());
    
    // Read the students in
    ifstream studentsFile(STUDENTS_FILE);
    assert (!studentsFile.fail());
    readStudents(studentsFile);
    studentsFile.close();   
    
    // Read the items in
    ifstream itemsFile(ITEMS_FILE);
    assert (!itemsFile.fail());
    readItems(itemsFile);
    itemsFile.close();
    
    // Read and execute commands
    ifstream commandsFile(COMMANDS_FILE);
    assert (!commandsFile.fail());
    readCommands(commandsFile);
    commandsFile.close();

}

// Reads a student from an input stream 
void Catalog::readStudents(istream& in) {
    while (in) {
        Student s;
        if (readStudent(in, s)) {
            addStudent(s, false);
        } else break;
    }
}

// Reads a series of items from an input stream
void Catalog::readItems(istream& in) {
    while (in) {
        Item i;
        if (readItem(in, i)) {
            addItem(i, false);
        } else break;
    }
}

// Reads a command from an input stream and executes it
void Catalog::readCommands(istream& in) {
    while (in) {
        string line, command, type;
        in >> std::ws;
        getline(in, line);

        if (!in) return;

        istringstream i(line);
        i >> std::ws >> command >> std::ws >> type;

        out << line << std::endl;
        
        if (command == "print") {
            if (type == "students") {
                // Print all students
                printStudents();
            } else if (type == "items") {
                // Print all items
                printItems();
            } else {
                // Print that student
                printStudent(type);
            }
        } else if (command == "add") {
            if (type == "item") {
                // Read an item
                Item item;
                if (readItem(in, item)) {
                    // Add it
                    addItem(item);
                } else {
                    out << "Failure" << endl;
                }
            } else if (type == "student") {
                // Read a student
                Student student;
                if (readStudent(in, student)) {
                    // Add it
                    addStudent(student);
                } else {
                    out << "Failure" << endl;
                }
            }
        } else if (command == "delete") {
            deleteStudent(type);
        } else if (command == "quit") {
            return;
        }
    }
}

// Reads in a student's information from an input stream
bool Catalog::readStudent(istream& in, Student& student) {
    while (in) {
        // Read a field name
        string field, data;
        getline(in, field);
        getline(in, data);
        
        if (field == "@Name:") {
            student.setName(data);
        } else if (field == "@Phone Number:") {
            student.setPhone(data);
        } else if (field == "@E-mail:") {
            student.setEmail(data);
        } else if (field == "@Address Line 1:") {
            student.setStreet(data);
        } else if (field == "@Address Line 2:") {
            student.setApt(data);
        } else if (field == "@City:") {
            student.setCity(data);
        } else if (field == "@State:") {
            student.setState(data);
        } else if (field == "@Zipcode:") {
            student.setZip(data);
        } else if (field == "@Other:") {
            student.setOther(data);
        } else {
            if (student.getEmail() == "") {
                return false;
            } else {
                student.setActive(true);
                return true;
            }
        }
    }
    return false;
}

// Reads an item's information from an input stream

bool Catalog::readItem(istream& in, Item& item) {
    while (in) {
        // Read a field name
        string field, data;
        getline(in, field);
        getline(in, data);
        
        if (field == "@Item:") {
            item.setName(data);
        } else if (field == "@Media Type:") {
            item.setType(data);
        } else if (field == "@by:") {
            item.setAuthor(data);
        } else if (field == "@Owner:") {
            item.setOwner(data);
        } else if (field == "@Price:") {
            item.setPrice(data);
        } else if (field == "@Availability:") {
            Availability a = NONE;
            for (int i = 0; i < 5; i++) {
                if (data == AVAILABILITIES[i]) {
                    a = Availability(i);
                    break;
                }
            }
            item.setAvailability(a);
        } else {
            if (item.getOwner() == "") {
                return false;
            } else {
                item.setActive(true);
                return true;
            }
        }
    }
    return false;
}

// Returns an index where the selected student is located, or
// -1 if student does not exist
int Catalog::findStudent(string email) {
    for (int i = 0; i < 100; i++) {
        if (students[i].isActive() && students[i].getEmail() == email) {
            return i;
        }
    }
    return -1;
}

// Returns the first item belonging to the student with the given email address
// at or following the given index, or -1 if no more items exist
int Catalog::findItem(string email, int start) {
    if (start < 0 || start >= 100) return -1;
    for (int i = start; i < 100; i++) {
        if (items[i].isActive() && items[i].getOwner() == email) {
            return i;
        }
    }
    return -1;
}

// Prints all students
void Catalog::printStudents() {
    for (int i = 0; i < 100; i++) {
        if (students[i].isActive()) {
            students[i].print(out);
        }
    }
}

// Prints all items
void Catalog::printItems() {
    for (int i = 0; i < 100; i++) {
        if (items[i].isActive()) {
            items[i].print(out);
        }
    }
}

// Prints student information and all items belonging to it
void Catalog::printStudent(string email) {
    // Try to find the student
    int index = findStudent(email);
    if (index == -1) {
        out << email << " not found." << endl;
        return;
    }
    students[index].print(out);
    // Print items belonging to the student
    index = -1;
    while ((index = findItem(email, index+1)) != -1) {
        items[index].print(out, false);
    }
}

// Adds an item
void Catalog::addItem(const Item& item, bool log) {
    // Make sure the owner exists
    if (findStudent(item.getOwner()) == -1) {
        if (log) out << "Failure" << endl;
        return;
    }
    // Try to find the first unused item space
    int i;
    for (i = 0; i < 100; i++) {
        if (items[i].isActive() == false) break;
    }
    if (i == 100) {
        if (log) out << "Failure" << endl;
        return;
    }
    // Copy the item into the space
    items[i] = item;
    if (log) out << "Success" << endl;
}

// Adds a student
void Catalog::addStudent(const Student& student, bool log) {
    // Make sure the student doesn't already exist
    if (findStudent(student.getEmail()) != -1) {
        if (log) out << "Failure" << endl;
        return;
    }
    // Try to find the first unused student space
    int i;
    for (i = 0; i < 100; i++) {
        if (students[i].isActive() == false) break;
    }
    if (i == 100) {
        if (log) out << "Failure" << endl;
        return;
    }
    // Copy the student into the space
    students[i] = student;
    if (log) out << "Success" << endl;
}

// Deletes a student's information and all items associated with it
void Catalog::deleteStudent(string email) {
    // Try to find the student
    int index = findStudent(email);
    if (index == -1) {
        out << "Failure" << endl;
        return;
    }
    // Delete the student
    students[index].setActive(false);
    
    // Try to find any items belonging to this student
    index = -1;
    while ((index = findItem(email, index+1)) != -1) {
        // Delete the item
        items[index].setActive(false);
    }

    out << "Success" << endl;
}