package wshub

import "testing"

func TestParseSignalKey(t *testing.T) {
	cases := []struct {
		in   string
		base string
		idx  int
	}{
		{"src:sig", "src:sig", -1},
		{"src:sig[0]", "src:sig", 0},
		{"src:sig[3]", "src:sig", 3},
		{"src:sig[x]", "src:sig[x]", -1},
		{"src:sig]", "src:sig]", -1},
	}
	for _, c := range cases {
		base, idx := parseSignalKey(c.in)
		if base != c.base || idx != c.idx {
			t.Errorf("parseSignalKey(%q) = (%q,%d), want (%q,%d)",
				c.in, base, idx, c.base, c.idx)
		}
	}
}

func armed(key, edge string, thr float64) *triggerEngine {
	te := newTriggerEngine()
	te.SetConfig(trigConfig{signalKey: key, edge: edge, threshold: thr,
		windowSec: 1, prePercent: 20, mode: "normal"})
	te.Arm()
	return te
}

func TestFeedRisingEdge(t *testing.T) {
	te := armed("src:sig", "rising", 0.5)
	te.feed("src:sig", 1, []float64{1, 2, 3, 4}, []float64{0, 0.2, 0.9, 1.0})
	if te.State() != trigCollecting {
		t.Fatalf("state = %q, want collecting", te.State())
	}
	// Fires at the sample that crossed, i.e. t=3.
	trigTime, pre, post, ok := te.dueCapture(1e9)
	if !ok || trigTime != 3 {
		t.Fatalf("dueCapture = (%v,%v), want trigTime 3", trigTime, ok)
	}
	if pre != 0.2 || post != 0.8 {
		t.Errorf("pre/post = %v/%v, want 0.2/0.8", pre, post)
	}
}

func TestFeedFallingEdgeIgnoresRising(t *testing.T) {
	te := armed("src:sig", "falling", 0.5)
	te.feed("src:sig", 1, []float64{1, 2, 3}, []float64{0, 0.9, 1.0})
	if te.State() != trigArmed {
		t.Fatalf("state = %q, want armed (no falling edge)", te.State())
	}
	te.feed("src:sig", 1, []float64{4, 5}, []float64{0.6, 0.1})
	if te.State() != trigCollecting {
		t.Fatalf("state = %q, want collecting", te.State())
	}
}

func TestFeedIgnoresOtherSignals(t *testing.T) {
	te := armed("src:sig", "rising", 0.5)
	te.feed("src:other", 1, []float64{1, 2}, []float64{0, 1})
	if te.State() != trigArmed {
		t.Fatalf("state = %q, want armed", te.State())
	}
}

func TestFeedArrayElementSelection(t *testing.T) {
	// 2-element signal, element-major: [e0,e1, e0,e1, ...]. Only element 1
	// crosses the threshold.
	te := armed("src:sig[1]", "rising", 0.5)
	tt := []float64{1, 1, 2, 2}
	vv := []float64{0, 0, 0, 1}
	te.feed("src:sig", 2, tt, vv)
	if te.State() != trigCollecting {
		t.Fatalf("state = %q, want collecting", te.State())
	}

	// Element 0 never crosses, so a config on [0] must not fire.
	te2 := armed("src:sig[0]", "rising", 0.5)
	te2.feed("src:sig", 2, tt, vv)
	if te2.State() != trigArmed {
		t.Fatalf("state = %q, want armed", te2.State())
	}
}

func TestForceUsesLastSampleTime(t *testing.T) {
	te := newTriggerEngine()
	te.SetConfig(trigConfig{signalKey: "src:sig", edge: "rising", threshold: 1e9,
		windowSec: 2, prePercent: 50, mode: "single"})
	te.Arm()
	te.feed("src:sig", 1, []float64{10, 11, 12}, []float64{0, 0, 0})
	if te.State() != trigArmed {
		t.Fatalf("state = %q, want armed (threshold unreachable)", te.State())
	}
	te.Force()
	trigTime, pre, post, ok := te.dueCapture(1e9)
	if !ok || trigTime != 12 || pre != 1 || post != 1 {
		t.Fatalf("dueCapture = (%v,%v,%v,%v), want (12,1,1,true)",
			trigTime, pre, post, ok)
	}
}

func TestForceFromIdle(t *testing.T) {
	te := newTriggerEngine()
	te.SetConfig(trigConfig{signalKey: "src:sig", edge: "rising",
		windowSec: 1, prePercent: 20, mode: "normal"})
	te.Force()
	if te.State() != trigCollecting {
		t.Fatalf("state = %q, want collecting", te.State())
	}
}

func TestCaptureMarginDelaysExtraction(t *testing.T) {
	te := armed("src:sig", "rising", 0.5)
	te.feed("src:sig", 1, []float64{0, 1}, []float64{0, 1}) // fires at t=1
	// post = 0.8 s; capture is due at 1 + 0.8 + 0.15.
	if _, _, _, ok := te.dueCapture(1.9); ok {
		t.Error("capture extracted before the margin elapsed")
	}
	if _, _, _, ok := te.dueCapture(1.96); !ok {
		t.Error("capture not extracted after the margin elapsed")
	}
}

func TestAutoRearmNormalMode(t *testing.T) {
	te := armed("src:sig", "rising", 0.5)
	te.feed("src:sig", 1, []float64{0, 1}, []float64{0, 1})
	te.markTriggered(100)
	if te.State() != trigTriggered {
		t.Fatalf("state = %q, want triggered", te.State())
	}
	if te.dueRearm(100.1) {
		t.Error("rearmed before the delay elapsed")
	}
	if !te.dueRearm(100.3) {
		t.Error("did not rearm after the delay elapsed")
	}
	if te.dueRearm(200) {
		t.Error("rearm was not consumed")
	}
}

func TestNoAutoRearmInSingleMode(t *testing.T) {
	te := newTriggerEngine()
	te.SetConfig(trigConfig{signalKey: "src:sig", edge: "rising", threshold: 0.5,
		windowSec: 1, prePercent: 20, mode: "single"})
	te.Arm()
	te.feed("src:sig", 1, []float64{0, 1}, []float64{0, 1})
	te.markTriggered(100)
	if te.dueRearm(200) {
		t.Error("single mode must not auto-rearm")
	}
}

func TestStoppedSuppressesRearm(t *testing.T) {
	te := armed("src:sig", "rising", 0.5)
	te.feed("src:sig", 1, []float64{0, 1}, []float64{0, 1})
	te.SetStopped(true)
	te.markTriggered(100)
	if te.dueRearm(200) {
		t.Error("stopped engine must not rearm")
	}
}

func TestSetConfigClamps(t *testing.T) {
	te := newTriggerEngine()
	te.SetConfig(trigConfig{signalKey: "s:x", windowSec: 100, prePercent: 500})
	if cfg := te.Config(); cfg.windowSec != 10 || cfg.prePercent != 100 {
		t.Errorf("upper clamp = %v/%v, want 10/100", cfg.windowSec, cfg.prePercent)
	}
	te.SetConfig(trigConfig{signalKey: "s:x", windowSec: 0, prePercent: -5})
	if cfg := te.Config(); cfg.windowSec != 1e-4 || cfg.prePercent != 0 {
		t.Errorf("lower clamp = %v/%v, want 1e-4/0", cfg.windowSec, cfg.prePercent)
	}
}

func TestActiveTracksConfiguredSignal(t *testing.T) {
	te := newTriggerEngine()
	if te.Active() {
		t.Error("a fresh engine must not be active")
	}
	te.SetConfig(trigConfig{signalKey: "src:sig", windowSec: 1})
	if !te.Active() {
		t.Error("engine must be active once a signal is configured")
	}
	// Rings must keep filling after a capture completes, not just while armed.
	te.Disarm()
	if !te.Active() {
		t.Error("engine must stay active after disarm while a signal is set")
	}
}