var circularBuffer = require('./circular-buffer').circularBuffer;
var bufferEmptyException = require('./circular-buffer').bufferEmptyException;
var bufferFullException = require('./circular-buffer').bufferFullException;

describe('CircularBuffer', function() {

  it('reading an empty buffer throws a BufferEmptyException', function() {
    var buffer = circularBuffer(1);
    expect(buffer.read).toThrow(bufferEmptyException());
  });

  xit('write and read back one item', function() {
    var buffer = circularBuffer(1);
    buffer.write('1');
    expect(buffer.read()).toBe('1');
    expect(buffer.read).toThrow(bufferEmptyException());
  });

  xit('write and read back multiple items', function() {
    var buffer = circularBuffer(2);
    buffer.write('1');
    buffer.write('2');
    expect(buffer.read()).toBe('1');
    expect(buffer.read()).toBe('2');
    expect(buffer.read).toThrow(bufferEmptyException());
  });

  xit('clearing a buffer', function() {
    var buffer = circularBuffer(2);
    buffer.write('1');
    buffer.write('2');
    buffer.clear();
    expect(buffer.read).toThrowError;
    buffer.write('3');
    buffer.write('4');
    expect(buffer.read()).toBe('3');
    expect(buffer.read()).toBe('4');
  });

  xit('alternate write and read', function() {
    var buffer = circularBuffer(2);
    buffer.write('1');
    expect(buffer.read()).toBe('1');
    buffer.write('2');
    expect(buffer.read()).toBe('2');
  });

  xit('reads back oldest item', function() {
    var buffer = circularBuffer(3);
    buffer.write('1');
    buffer.write('2');
    buffer.read();
    buffer.write('3');
    expect(buffer.read()).toBe('2');
    expect(buffer.read()).toBe('3');
  });

  xit('writes of undefined or null don\'t occupy buffer', function() {
    var buffer = circularBuffer(3);
    buffer.write(null);
    buffer.write(undefined);
    [1,2,3].map(function(i) { buffer.write(i.toString()); });
    expect(buffer.read()).toBe('1');
  });

  xit('writing to a full buffer throws a BufferFullException', function() {
    var buffer = circularBuffer(2);
    buffer.write('1');
    buffer.write('2');
    expect(function() {
      buffer.write('A');
    }).toThrow(bufferFullException());
  });

  xit('forced writes over write oldest item in a full buffer', function() {
    var buffer = circularBuffer(2);
    buffer.write('1');
    buffer.write('2');
    buffer.forceWrite('A');
    expect(buffer.read()).toBe('2');
    expect(buffer.read()).toBe('A');
    expect(buffer.read).toThrow(bufferEmptyException());
  });

  xit('forced writes act like write in a non-full buffer', function() {
    var buffer = circularBuffer(2);
    buffer.write('1');
    buffer.forceWrite('2');
    expect(buffer.read()).toBe('1');
    expect(buffer.read()).toBe('2');
    expect(buffer.read).toThrow(bufferEmptyException());
  });

  xit('alternate force write and read into full buffer', function() {
    var buffer = circularBuffer(5);
    [1,2,3].map(function(i) { buffer.write(i.toString()); });
    buffer.read();
    buffer.read();
    buffer.write('4');
    buffer.read();
    [5,6,7,8].map(function(i) { buffer.write(i.toString()); });
    buffer.forceWrite('A');
    buffer.forceWrite('B');
    expect(buffer.read()).toBe('6');
    expect(buffer.read()).toBe('7');
    expect(buffer.read()).toBe('8');
    expect(buffer.read()).toBe('A');
    expect(buffer.read()).toBe('B');
    expect(buffer.read).toThrow(bufferEmptyException());
  });

  xit('multiple buffers don\'t interfere with each other', function() {
    var buffer1 = circularBuffer(1);
    var buffer2 = circularBuffer(1);
    buffer1.write('1');
    expect(buffer2.read).toThrow(bufferEmptyException());
    expect(buffer1.read()).toBe('1');
  });

});