package aioe

import "testing"

// TestSimulationCharacterization is the calibration proof for the model card: across every standard
// regime the sum stays exactly 1, the clamps always hold, and the directional regimes move the
// intended dimension the intended way while noise leaves the weights put.
func TestSimulationCharacterization(t *testing.T) {
	p := DefaultParams()
	byName := map[string]Simulation{}
	for _, r := range StandardRegimes() {
		s := Simulate(r, 40, 200, p)
		if !s.SumAlways1 {
			t.Fatalf("regime %s broke the sum-to-one invariant", r.Name)
		}
		if !s.ClampsHeld {
			t.Fatalf("regime %s escaped the clamps", r.Name)
		}
		byName[r.Name] = s
	}

	if !byName["rewards-skills"].End["skills"].GreaterThan(byName["rewards-skills"].Start["skills"]) {
		t.Fatal("rewards-skills must raise the skills weight")
	}
	if !byName["penalizes-location"].End["location"].LessThan(byName["penalizes-location"].Start["location"]) {
		t.Fatal("penalizes-location must lower the location weight")
	}
	// Pure noise must not meaningfully move any weight (within a grain or two of rounding).
	noise := byName["pure-noise"]
	for _, d := range Dimensions {
		if noise.End[d].Sub(noise.Start[d]).Abs().GreaterThan(dec("0.001")) {
			t.Fatalf("pure noise moved %s by more than a rounding grain: %s -> %s", d, noise.Start[d], noise.End[d])
		}
	}
	// The adversarial flip must stay bounded (clamps held above) and not blow the sum.
	if !byName["adversarial-flip"].SumAlways1 {
		t.Fatal("adversarial flip broke the sum invariant")
	}
}

func TestSimulateIsDeterministic(t *testing.T) {
	p := DefaultParams()
	r := StandardRegimes()[0]
	a := Simulate(r, 30, 100, p)
	b := Simulate(r, 30, 100, p)
	if a.Report() != b.Report() {
		t.Fatal("same regime and params must produce an identical report")
	}
}