package emotion

import "testing"

// TestReactClassifiesTurns locks the turn reading the observer applies: anger and
// negative cues outrank positive ones, strong warmth outranks mild warmth, and a
// cue-free turn carries no signal (so the machine is left to decay, not jump).
func TestReactClassifiesTurns(t *testing.T) {
	t.Parallel()
	cases := []struct {
		name  string
		text  string
		state EmotionState
		delta int
		sig   bool
	}{
		{name: "empty", text: "", sig: false},
		{name: "plain task", text: "帮我把这个文件重命名一下", sig: false},
		{name: "mild warm", text: "今天谢谢你呀", state: Happy, delta: affectionUp, sig: true},
		{name: "greeting", text: "早上好", state: Happy, delta: affectionUp, sig: true},
		{name: "strong warm", text: "我太开心了，最喜欢你了", state: Excited, delta: affectionUp, sig: true},
		{name: "down", text: "今天有点难过", state: Sad, delta: affectionDown, sig: true},
		{name: "tired", text: "我好累", state: Sad, delta: affectionDown, sig: true},
		{name: "angry", text: "别烦我了", state: Angry, delta: affectionDown, sig: true},
		// "不开心" contains "开心": the negative reading must win, otherwise a
		// complaint would raise the mood.
		{name: "negated positive", text: "我不开心", state: Sad, delta: affectionDown, sig: true},
		{name: "ascii warm", text: "thanks, miss you", state: Happy, delta: affectionUp, sig: true},
	}
	for _, tc := range cases {
		t.Run(tc.name, func(t *testing.T) {
			t.Parallel()
			got := React(tc.text)
			if got.Signal != tc.sig {
				t.Fatalf("React(%q).Signal = %v, want %v", tc.text, got.Signal, tc.sig)
			}
			if !tc.sig {
				return
			}
			if got.State != tc.state || got.AffectionDelta != tc.delta {
				t.Fatalf("React(%q) = {%s, %d}, want {%s, %d}", tc.text, got.State, got.AffectionDelta, tc.state, tc.delta)
			}
		})
	}
}

// TestMachineMoveWalksTransitions verifies Move honors the installed transition
// table instead of forcing a state: an installed edge is taken directly, and an
// emotion two edges away is reached through the legal intermediate (the default
// table has no calm→angry or calm→excited edge).
func TestMachineMoveWalksTransitions(t *testing.T) {
	t.Parallel()
	m, err := NewMachine(Params{InitialState: Calm})
	if err != nil {
		t.Fatalf("NewMachine: %v", err)
	}

	if got := m.Move(Happy); got != Happy {
		t.Fatalf("calm → happy = %s, want direct happy", got)
	}
	m.Set(Calm)
	if got := m.Move(Angry); got != Sad {
		t.Fatalf("calm → angry = %s, want the legal intermediate sad", got)
	}
	if got := m.Move(Angry); got != Angry {
		t.Fatalf("sad → angry = %s, want direct angry", got)
	}
	m.Set(Calm)
	if got := m.Move(Excited); got != Happy {
		t.Fatalf("calm → excited = %s, want the legal intermediate happy", got)
	}
	// A target with no legal path leaves the machine where it was.
	p, err := NewMachine(Params{
		InitialState: Calm,
		Transitions:  map[EmotionState][]EmotionState{Calm: {Happy}},
	})
	if err != nil {
		t.Fatalf("NewMachine: %v", err)
	}
	if got := p.Move(Sad); got != Calm {
		t.Fatalf("unreachable move = %s, want calm unchanged", got)
	}
	if got := m.Move(""); got != m.Current() {
		t.Fatalf("empty target moved to %s, want unchanged", got)
	}
}

// TestMachineMoveHonorsCustomTable verifies a persona's own transition table wins:
// a custom edge that skips the built-in intermediate is taken directly.
func TestMachineMoveHonorsCustomTable(t *testing.T) {
	t.Parallel()
	m, err := NewMachine(Params{
		InitialState: Calm,
		Transitions: map[EmotionState][]EmotionState{
			Calm:    {Excited},
			Excited: {Calm},
		},
	})
	if err != nil {
		t.Fatalf("NewMachine: %v", err)
	}
	if got := m.Move(Excited); got != Excited {
		t.Fatalf("custom calm → excited = %s, want direct excited", got)
	}
}