package status

import (
	"reflect"
	"testing"
)

func TestEvaluate(t *testing.T) {
	valid := func(power float64) Sample { return Sample{Power: power, Valid: true} }
	for _, tt := range []struct {
		name    string
		samples []Sample
		state   string
		message string
	}{
		{"no samples", nil, "waiting", "Waiting for data..."},
		{"one sample", []Sample{valid(10)}, "waiting", "Waiting for data..."},
		{"two samples with gap", []Sample{valid(10), {}}, "waiting", "Waiting for data..."},
		{"all zero", []Sample{valid(0), valid(0), valid(0)}, "done", "Laundry done"},
		{"below threshold", []Sample{valid(2.99), valid(2.99), valid(2.99)}, "done", "Laundry done"},
		{"at threshold", []Sample{valid(0), valid(3), valid(0)}, "running", "Laundry not yet done"},
		{"mixed", []Sample{valid(47.7), valid(0), valid(2.99)}, "running", "Laundry not yet done"},
		{"gap overrides active", []Sample{valid(47.7), {}, valid(0)}, "incomplete", "Incomplete data"},
		{"all missing", []Sample{{}, {}, {}}, "incomplete", "Incomplete data"},
	} {
		t.Run(tt.name, func(t *testing.T) {
			got := Evaluate(tt.samples)
			if got.State != tt.state || got.Message != tt.message {
				t.Fatalf("Evaluate() = %q, %q; want %q, %q", got.State, got.Message, tt.state, tt.message)
			}
			if len(got.Readings) != len(tt.samples) || got.Readings == nil {
				t.Fatalf("readings = %#v; want non-nil slice of length %d", got.Readings, len(tt.samples))
			}
			for i, sample := range tt.samples {
				if got.Readings[i] != sample {
					t.Errorf("readings[%d] = %+v; want %+v", i, got.Readings[i], sample)
				}
			}
		})
	}
}

func TestWindowKeepsLastThreeOldestFirst(t *testing.T) {
	var window Window
	if got := window.Readings(); len(got) != 0 {
		t.Fatalf("new window = %v", got)
	}
	for i := range 7 {
		window.Add(Sample{Power: float64(i), Valid: true})
	}
	want := []Sample{{Power: 4, Valid: true}, {Power: 5, Valid: true}, {Power: 6, Valid: true}}
	if got := window.Readings(); !reflect.DeepEqual(got, want) {
		t.Fatalf("Readings() = %v; want %v", got, want)
	}
	snapshot := window.Readings()
	snapshot[0].Power = 999
	if got := window.Readings(); !reflect.DeepEqual(got, want) {
		t.Fatal("mutating a snapshot changed the window")
	}
	for range 3 {
		window.Add(Sample{Valid: true})
	}
	if got := Evaluate(window.Readings()); got.State != "done" {
		t.Fatalf("old active samples did not age out: %+v", got)
	}
	window.Add(Sample{})
	if got := Evaluate(window.Readings()); got.State != "incomplete" {
		t.Fatalf("missing sample was not recorded: %+v", got)
	}
}