#ifndef MATRIX_H
#define MATRIX_H

#include <iostream>

class Matrix {
public:
    // Constructors & Destructor
    Matrix();  // Default constructor (creates an empty 0 x 0 matrix)
    Matrix(unsigned int rows, unsigned int cols, double fill);
    Matrix(const Matrix &other);
    ~Matrix();

    Matrix& operator=(const Matrix &other);

    // Accessors for dimensions
    unsigned int num_rows() const;
    unsigned int num_cols() const;

    // Clears the matrix (deallocates any memory and sets size to 0 x 0)
    void clear();

    // Safe accessor and modifier methods
    bool get(unsigned int row, unsigned int col, double &value) const;
    bool set(unsigned int row, unsigned int col, double value);

    // Simple matrix operations
    void multiply_by_coefficient(double coefficient);
    bool swap_row(unsigned int row1, unsigned int row2);
    void transpose();

    // Binary matrix operations (modifies this matrix)
    bool add(const Matrix &other);
    bool subtract(const Matrix &other);

    // Advanced accessors: returns a dynamic array with the requested row or column.
    // The caller is responsible for deleting the returned array.
    double* get_row(unsigned int row) const;
    double* get_col(unsigned int col) const;

    // Quarter the matrix into four equally sized quadrants.
    // The four matrices are returned in a dynamically allocated array in the order:
    // UL, UR, LL, LR.
    // If the matrix is too small (i.e. less than 2 rows or 2 cols), returns four empty matrices.
    Matrix* quarter() const;

    // Equality operators
    bool operator==(const Matrix &other) const;
    bool operator!=(const Matrix &other) const;

    // Friend overloaded output operator for printing the matrix.
    friend std::ostream& operator<<(std::ostream &out, const Matrix &m);

private:
    unsigned int rows;
    unsigned int cols;
    double** data;

    // Helper functions to allocate and deallocate the 2D array.
    void allocate(unsigned int r, unsigned int c, double fill);
    void deallocate();
};

#endif