define(["helper/Offline", "helper/Basic", "Test", "Tone/signal/Signal",
	"Tone/type/Type", "Tone/core/Transport", "Tone/component/LFO", "helper/ConstantOutput"],
	function (Offline, Basic, Test, Signal, Tone, Transport, LFO, ConstantOutput) {

	describe("Signal", function(){

		Basic(Signal);

		context("Signal Rate Value", function(){

			it("handles input and output connections", function(){
				var signal = new Signal();
				Test.connect(signal);
				signal.connect(Test);
				signal.dispose();
			});

			it("can be created with an options object", function(){
				var signal = new Signal({
					"value" : 0.2,
					"units" : Tone.Type.Positive
				});
				expect(signal.value).to.be.closeTo(0.2, 0.001);
				expect(signal.units).to.equal(Tone.Type.Positive);
				signal.dispose();
			});

			it("can start with a value initially", function(){
				var signal = new Signal(2);
				expect(signal.value).to.equal(2);
				signal.dispose();
			});

			it("can set a value", function(){
				var signal = new Signal(0);
				signal.value = 10;
				expect(signal.value).to.equal(10);
				signal.dispose();
			});

			it("takes on another signal's value when connected", function(){
				return ConstantOutput(function(){
					var sigA = new Signal(0).toMaster();
					new Signal(3).connect(sigA);
				}, 3);
			});
		});

		context("Scheduling", function(){

			it ("can be scheduled to set a value in the future", function(){
				return Offline(function(){
					var sig = new Signal(0).toMaster();
					sig.setValueAtTime(2, 0.2);
				}, 0.3).then(function(buffer){
					buffer.forEach(function(sample, time){
						if (time < 0.19){
							expect(sample).to.be.closeTo(0, 0.001);
						} else if (time > 0.2){
							expect(sample).to.be.closeTo(2, 0.001);
						}
					});
				});
			});

			it ("can linear ramp from the current value to another value in the future", function(){
				return Offline(function(){
					var sig = new Signal(0).toMaster();
					sig.setValueAtTime(0, 0);
					sig.linearRampToValueAtTime(1, 1);
				}, 1).then(function(buffer){
					buffer.forEach(function(sample, time){
						expect(sample).to.be.closeTo(time, 0.001);
					});
				});
			});

			it ("can schedule an exponential ramp", function(){
				var sig = new Signal(1);
				sig.exponentialRampToValueAtTime(3, 1);
				sig.dispose();
			});

			it ("can approach a target value", function(){
				var sig = new Signal(1);
				sig.setTargetAtTime(0.2, 1, 2);
				sig.dispose();
			});

			it ("can set a ramp point at the current value", function(){
				var sig = new Signal(1);
				sig.setRampPoint();
				sig.dispose();
			});

			it ("can schedule multiple automations", function(){
				return Offline(function(){
					var sig = new Signal(0).toMaster();
					sig.setValueAtTime(0, 0);
					sig.linearRampToValueAtTime(0.5, 0.5);
					sig.linearRampToValueAtTime(0, 1);
				}, 1).then(function(buffer){
					buffer.forEach(function(sample, time){
						if (time < 0.5){
							expect(sample).to.be.closeTo(time, 0.01);
						} else {
							expect(sample).to.be.closeTo(1 - time, 0.01);
						}
					});
				});
			});

			it ("can cancel an automation", function(){
				return ConstantOutput(function(){
					var sig = new Signal(1).toMaster();
					sig.setValueAtTime(4, 0.1);
					sig.exponentialRampToValueAtTime(3, 0.2);
					sig.cancelScheduledValues(0);
				}, 1);
			});

			it ("can cancel and hold an automation curve", function(){
				return Offline(function(){
					var sig = new Signal(0).toMaster();
					sig.linearRampTo(2, 1);
					sig.cancelAndHoldAtTime(0.5)
				}, 1).then(function(buffer){
					expect(buffer.getValueAtTime(0)).to.be.closeTo(0, 0.1);
					expect(buffer.getValueAtTime(0.25)).to.be.closeTo(0.5, 0.1);
					expect(buffer.getValueAtTime(0.5)).to.be.closeTo(1, 0.1);
					expect(buffer.getValueAtTime(0.75)).to.be.closeTo(1, 0.1);
				});
			});

			it ("can set a linear ramp from the current time", function(){
				return Offline(function(){
					var sig = new Signal(0).toMaster();
					sig.linearRampTo(2, 0.3);
				}, 0.5).then(function(buffer){
					buffer.forEach(function(sample, time){
						if (time > 0.3){
							expect(sample).to.be.closeTo(2, 0.02);
						}
					});
				});
			});

			it ("can set an linear ramp in the future", function(){
				return Offline(function(){
					var sig = new Signal(1).toMaster();
					sig.linearRampTo(50, 0.3, 0.2);
				}, 0.6).then(function(buffer){
					buffer.forEach(function(sample, time){
						if (time >= 0.6){
							expect(sample).to.be.closeTo(50, 0.5);
						} else if (time < 0.2){
							expect(sample).to.equal(1);
						}
					});
				});
			});


			it ("can set an exponential ramp from the current time", function(){
				return Offline(function(){
					var sig = new Signal(1).toMaster();
					sig.exponentialRampTo(50, 0.4);
				}, 0.6).then(function(buffer){
					buffer.forEach(function(sample, time){
						if (time >= 0.4){
							expect(sample).to.be.closeTo(50, 0.5);
						} else if (time < 0.39){
							expect(sample).to.be.lessThan(50);
						}
					});
				});
			});

			it ("can set an exponential ramp in the future", function(){
				return Offline(function(){
					var sig = new Signal(1).toMaster();
					sig.exponentialRampTo(50, 0.3, 0.2);
				}, 0.8).then(function(buffer){
					buffer.forEach(function(sample, time){
						if (time >= 0.6){
							expect(sample).to.be.closeTo(50, 0.5);
						} else if (time < 0.2){
							expect(sample).to.equal(1);
						}
					});
				});
			});

			it ("rampTo ramps from the current value", function(){
				return Offline(function(){
					var sig = new Signal(3).toMaster();
					sig.rampTo(0.2, 0.1);
				}, 0.4).then(function(buffer){
					buffer.forEach(function(sample, time){
						if (time >= 0.1){
							expect(sample).to.be.closeTo(0.2, 0.1);
						} else {
							expect(sample).to.be.greaterThan(0.2);
						}
					});
				});
			});

			it ("rampTo ramps from the current value at a specific time", function(){
				return Offline(function(){
					var sig = new Signal(0).toMaster();
					sig.rampTo(2, 0.1, 0.4);
				}, 0.6).then(function(buffer){
					buffer.forEach(function(sample, time){
						if (time < 0.4){
						expect(sample).to.be.closeTo(0, 0.1);
					} else if (time > 0.5){
						expect(sample).to.be.closeTo(2, 0.1);
					}
					});
				});
			});

		});

		context("Units", function(){

			it("can be created with specific units", function(){
				var signal = new Signal(0, Tone.Type.BPM);
				expect(signal.units).to.equal(Tone.Type.BPM);
				signal.dispose();
			});

			it("can evaluate the given units", function(){
				var signal = new Signal(2, Tone.Type.Time);
				signal.value = "4n";
				expect(signal.value).to.be.closeTo(0.5, 0.001);
				signal.dispose();
			});

			it("converts the given units when passed in the constructor", function(){
				return ConstantOutput(function(){
					var signal = new Signal({
						"value" : -10,
						"units" : Tone.Type.Decibels,
					}).toMaster();
				}, 0.315);
			});

			it("can be set to not convert the given units", function(){
				return ConstantOutput(function(){
					var signal = new Signal({
						"value" : -10,
						"units" : Tone.Type.Decibels,
						"convert" : false
					}).toMaster();
				}, -10);
			});

			it("converts Frequency units", function(){
				var signal = new Signal("50hz", Tone.Type.Frequency);
				expect(signal.value).to.be.closeTo(50, 0.01);
				signal.dispose();
			});

			it("converts Time units", function(){
				var signal = new Signal("4n", Tone.Type.Time);
				expect(signal.value).to.be.closeTo(0.5, 0.01);
				signal.dispose();
			});

			it("converts NormalRange units", function(){
				var signal = new Signal(2, Tone.Type.NormalRange);
				expect(signal.value).to.be.closeTo(1, 0.01);
				signal.dispose();
			});

			it("converts AudioRange units", function(){
				var signal = new Signal(-2, Tone.Type.AudioRange);
				expect(signal.value).to.be.closeTo(-1, 0.01);
				signal.dispose();
			});

			it("converts Positive units", function(){
				var signal = new Signal(-2, Tone.Type.Positive);
				expect(signal.value).to.be.closeTo(0, 0.01);
				signal.dispose();
			});

		});

		context("Transport Syncing", function(){

			it("maintains its original value after being synced to the transport", function(){
				return ConstantOutput(function(Transport){
					var sig = new Signal(3).toMaster();
					Transport.syncSignal(sig);
				}, 3);
			});

			it("keeps the ratio when the bpm changes", function(){
				return ConstantOutput(function(Transport){
					Transport.bpm.value = 120;
					var sig = new Signal(5).toMaster();
					Transport.syncSignal(sig);
					Transport.bpm.value = 240;
				}, 10);
			});

			it("can ramp along with the bpm", function(){
				return Offline(function(Transport){
					Transport.bpm.value = 120;
					var sig = new Signal(2).toMaster();
					Transport.syncSignal(sig);
					Transport.bpm.rampTo(240, 0.5);
				}).then(function(buffer){
					buffer.forEach(function(sample, time){
						if (time >= 0.5){
							expect(sample).to.be.closeTo(4, 0.04);
						} else if (time < 0.4){
							expect(sample).to.be.within(1.95, 3);
						}
					});
				});
			});

			it("returns to the original value when unsynced", function(){
				return ConstantOutput(function(Transport){
					Transport.bpm.value = 120;
					var sig = new Signal(5).toMaster();
					Transport.syncSignal(sig);
					Transport.bpm.value = 240;
					Transport.unsyncSignal(sig);
				}, 5);
			});
		});

		context("LFO", function(){

			it ("can create an LFO from the constructor", function(){
				var sig = new Signal({
					"lfo" : {
						"min" : -20,
						"max" : 20
					}
				});
				expect(sig.lfo).to.be.instanceOf(LFO);
				expect(sig.lfo.min).to.be.closeTo(-20, 0.1);
				expect(sig.lfo.max).to.be.closeTo(20, 0.1);
			});

			it ("can set an LFO as the .value", function(){
				var sig = new Signal();
				sig.value = {
					"min" : 20,
					"max" : -20
				};
				expect(sig.lfo).to.be.instanceOf(LFO);
				expect(sig.lfo.min).to.be.closeTo(20, 0.1);
				expect(sig.lfo.max).to.be.closeTo(-20, 0.1);
			});

			it ("outputs a modulated signal", function(){
				return Offline(function(){
					new Signal({
						"lfo" : {
							"min" : 10,
							"max" : 20
						}
					}).toMaster();
				}, 0.4).then(function(buffer){
					buffer.forEach(function(sample){
						expect(sample).to.be.within(10, 20);
					});
				});
			});

			it ("can handle multiple levels of lfo", function(){
				return Offline(function(){
					new Signal({
						"lfo" : {
							"min" : 10,
							"max" : 20,
							"type" : "square",
							"frequency" : {
								"lfo" : {
									"min" : 2,
									"max" : 3,
									"frequency" : 10,
								}
							},
							"amplitude" : {
								"lfo" : {
									"min" : 0,
									"max" : 1,
									"frequency" : {
										"lfo" : {
											"min" : 2,
											"max" : 3,
											"frequency" : 10,
										}
									},
								}
							}
						}
					}).toMaster();
				}, 0.4).then(function(buffer){
					buffer.forEach(function(sample){
						expect(sample).to.be.within(10, 20);
					});
				});
			});
		});
	});
});