package app

import (
	"context"
	"errors"
	"reflect"
	"testing"
	"time"

	"gitea.nik4nao.com/nik/home-services/ha-gateway/internal/core/domain"
	"gitea.nik4nao.com/nik/home-services/ha-gateway/internal/core/ports/driven"
)

func TestSwitchAppRefresh(t *testing.T) {
	t.Run("filters non-switch entities and populates cache", func(t *testing.T) {
		ha := &mockHAClient{
			listStatesFunc: func(ctx context.Context) ([]*driven.HAState, error) {
				return []*driven.HAState{
					{
						EntityID: "switch.fan",
						State:    "on",
						Attributes: map[string]any{
							"friendly_name": "Fan",
							"device_class":  "switch",
						},
					},
					{
						EntityID: "light.kitchen",
						State:    "on",
					},
					{
						EntityID: "switch.heater",
						State:    "off",
						Attributes: map[string]any{
							"friendly_name": "Heater",
						},
					},
				}, nil
			},
		}

		app := NewSwitchApp(ha)
		if err := app.Refresh(context.Background()); err != nil {
			t.Fatalf("Refresh() error = %v", err)
		}

		got := app.cache
		want := []domain.Switch{
			{EntityID: "switch.fan", FriendlyName: "Fan", State: "on", DeviceClass: "switch"},
			{EntityID: "switch.heater", FriendlyName: "Heater", State: "off"},
		}
		if !reflect.DeepEqual(got, want) {
			t.Fatalf("cache = %#v, want %#v", got, want)
		}
	})
}

func TestSwitchAppListSwitches(t *testing.T) {
	t.Run("uses cache when populated", func(t *testing.T) {
		calls := 0
		app := NewSwitchApp(&mockHAClient{
			listStatesFunc: func(ctx context.Context) ([]*driven.HAState, error) {
				calls++
				return nil, nil
			},
		})
		app.cache = []domain.Switch{{EntityID: "switch.fan", State: "on"}}

		got, err := app.ListSwitches(context.Background())
		if err != nil {
			t.Fatalf("ListSwitches() error = %v", err)
		}
		if calls != 0 {
			t.Fatalf("ListStates() calls = %d, want 0", calls)
		}
		if !reflect.DeepEqual(got, app.cache) {
			t.Fatalf("ListSwitches() = %#v, want %#v", got, app.cache)
		}
	})

	t.Run("calls ListStates when cache is nil", func(t *testing.T) {
		calls := 0
		app := NewSwitchApp(&mockHAClient{
			listStatesFunc: func(ctx context.Context) ([]*driven.HAState, error) {
				calls++
				return []*driven.HAState{
					{EntityID: "switch.fan", State: "on"},
					{EntityID: "sensor.temp", State: "21"},
				}, nil
			},
		})

		got, err := app.ListSwitches(context.Background())
		if err != nil {
			t.Fatalf("ListSwitches() error = %v", err)
		}
		if calls != 1 {
			t.Fatalf("ListStates() calls = %d, want 1", calls)
		}
		want := []domain.Switch{{EntityID: "switch.fan", State: "on"}}
		if !reflect.DeepEqual(got, want) {
			t.Fatalf("ListSwitches() = %#v, want %#v", got, want)
		}
	})

	t.Run("propagates refresh error", func(t *testing.T) {
		wantErr := errors.New("list failed")
		app := NewSwitchApp(&mockHAClient{
			listStatesFunc: func(ctx context.Context) ([]*driven.HAState, error) {
				return nil, wantErr
			},
		})

		_, err := app.ListSwitches(context.Background())
		if !errors.Is(err, wantErr) {
			t.Fatalf("ListSwitches() error = %v, want %v", err, wantErr)
		}
	})
}

func TestSwitchAppTurnOn(t *testing.T) {
	now := time.Date(2026, 4, 9, 10, 0, 0, 0, time.UTC)
	callState := &driven.HAState{
		EntityID:    "switch.fan",
		State:       "on",
		Attributes:  map[string]any{"friendly_name": "Fan"},
		LastChanged: now,
		LastUpdated: now,
	}
	fallbackState := &driven.HAState{
		EntityID:    "switch.fan",
		State:       "on",
		Attributes:  map[string]any{"friendly_name": "Fan", "source": "fallback"},
		LastChanged: now,
		LastUpdated: now,
	}

	t.Run("happy path", func(t *testing.T) {
		app := NewSwitchApp(&mockHAClient{
			callServiceFunc: func(ctx context.Context, svcDomain, service string, payload map[string]any) ([]*driven.HAState, error) {
				if svcDomain != "switch" || service != "turn_on" {
					t.Fatalf("CallService() domain/service = %s/%s", svcDomain, service)
				}
				wantPayload := map[string]any{"entity_id": "switch.fan"}
				if !reflect.DeepEqual(payload, wantPayload) {
					t.Fatalf("payload = %#v, want %#v", payload, wantPayload)
				}
				return []*driven.HAState{callState}, nil
			},
		})

		got, err := app.TurnOn(context.Background(), "switch.fan")
		if err != nil {
			t.Fatalf("TurnOn() error = %v", err)
		}
		if !reflect.DeepEqual(got, haStateToDomain(callState)) {
			t.Fatalf("TurnOn() = %#v, want %#v", got, haStateToDomain(callState))
		}
	})

	t.Run("falls back to GetState when service returns empty list", func(t *testing.T) {
		getStateCalls := 0
		app := NewSwitchApp(&mockHAClient{
			callServiceFunc: func(ctx context.Context, svcDomain, service string, payload map[string]any) ([]*driven.HAState, error) {
				return []*driven.HAState{}, nil
			},
			getStateFunc: func(ctx context.Context, entityID string) (*driven.HAState, error) {
				getStateCalls++
				if entityID != "switch.fan" {
					t.Fatalf("GetState() entityID = %q, want %q", entityID, "switch.fan")
				}
				return fallbackState, nil
			},
		})

		got, err := app.TurnOn(context.Background(), "switch.fan")
		if err != nil {
			t.Fatalf("TurnOn() error = %v", err)
		}
		if getStateCalls != 1 {
			t.Fatalf("GetState() calls = %d, want 1", getStateCalls)
		}
		if !reflect.DeepEqual(got, haStateToDomain(fallbackState)) {
			t.Fatalf("TurnOn() = %#v, want %#v", got, haStateToDomain(fallbackState))
		}
	})

	t.Run("returns CallService error", func(t *testing.T) {
		wantErr := errors.New("call failed")
		app := NewSwitchApp(&mockHAClient{
			callServiceFunc: func(ctx context.Context, svcDomain, service string, payload map[string]any) ([]*driven.HAState, error) {
				return nil, wantErr
			},
		})

		_, err := app.TurnOn(context.Background(), "switch.fan")
		if !errors.Is(err, wantErr) {
			t.Fatalf("TurnOn() error = %v, want %v", err, wantErr)
		}
	})
}

func TestSwitchAppTurnOff(t *testing.T) {
	now := time.Date(2026, 4, 9, 10, 0, 0, 0, time.UTC)
	state := &driven.HAState{
		EntityID:    "switch.fan",
		State:       "off",
		Attributes:  map[string]any{"friendly_name": "Fan"},
		LastChanged: now,
		LastUpdated: now,
	}

	t.Run("happy path", func(t *testing.T) {
		app := NewSwitchApp(&mockHAClient{
			callServiceFunc: func(ctx context.Context, svcDomain, service string, payload map[string]any) ([]*driven.HAState, error) {
				if svcDomain != "switch" || service != "turn_off" {
					t.Fatalf("CallService() domain/service = %s/%s", svcDomain, service)
				}
				wantPayload := map[string]any{"entity_id": "switch.fan"}
				if !reflect.DeepEqual(payload, wantPayload) {
					t.Fatalf("payload = %#v, want %#v", payload, wantPayload)
				}
				return []*driven.HAState{state}, nil
			},
		})

		got, err := app.TurnOff(context.Background(), "switch.fan")
		if err != nil {
			t.Fatalf("TurnOff() error = %v", err)
		}
		if !reflect.DeepEqual(got, haStateToDomain(state)) {
			t.Fatalf("TurnOff() = %#v, want %#v", got, haStateToDomain(state))
		}
	})

	t.Run("error path", func(t *testing.T) {
		wantErr := errors.New("turn off failed")
		app := NewSwitchApp(&mockHAClient{
			callServiceFunc: func(ctx context.Context, svcDomain, service string, payload map[string]any) ([]*driven.HAState, error) {
				return nil, wantErr
			},
		})

		_, err := app.TurnOff(context.Background(), "switch.fan")
		if !errors.Is(err, wantErr) {
			t.Fatalf("TurnOff() error = %v, want %v", err, wantErr)
		}
	})
}

func TestSwitchAppToggle(t *testing.T) {
	now := time.Date(2026, 4, 9, 10, 0, 0, 0, time.UTC)
	state := &driven.HAState{
		EntityID:    "switch.fan",
		State:       "on",
		Attributes:  map[string]any{"friendly_name": "Fan"},
		LastChanged: now,
		LastUpdated: now,
	}

	t.Run("happy path", func(t *testing.T) {
		app := NewSwitchApp(&mockHAClient{
			callServiceFunc: func(ctx context.Context, svcDomain, service string, payload map[string]any) ([]*driven.HAState, error) {
				if svcDomain != "switch" || service != "toggle" {
					t.Fatalf("CallService() domain/service = %s/%s", svcDomain, service)
				}
				wantPayload := map[string]any{"entity_id": "switch.fan"}
				if !reflect.DeepEqual(payload, wantPayload) {
					t.Fatalf("payload = %#v, want %#v", payload, wantPayload)
				}
				return []*driven.HAState{state}, nil
			},
		})

		got, err := app.Toggle(context.Background(), "switch.fan")
		if err != nil {
			t.Fatalf("Toggle() error = %v", err)
		}
		if !reflect.DeepEqual(got, haStateToDomain(state)) {
			t.Fatalf("Toggle() = %#v, want %#v", got, haStateToDomain(state))
		}
	})

	t.Run("error path", func(t *testing.T) {
		wantErr := errors.New("toggle failed")
		app := NewSwitchApp(&mockHAClient{
			callServiceFunc: func(ctx context.Context, svcDomain, service string, payload map[string]any) ([]*driven.HAState, error) {
				return nil, wantErr
			},
		})

		_, err := app.Toggle(context.Background(), "switch.fan")
		if !errors.Is(err, wantErr) {
			t.Fatalf("Toggle() error = %v, want %v", err, wantErr)
		}
	})
}