package nws

import (
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"gitea.maximumdirect.net/ejr/feedkit/config"
	"gitea.maximumdirect.net/ejr/feedkit/event"
	"gitea.maximumdirect.net/ejr/weatherfeeder/standards"
)

type forecastPoller interface {
	Poll(ctx context.Context) ([]event.Event, error)
}

func TestForecastSourcesEmitExpectedSchemaAndPreferGeneratedAt(t *testing.T) {
	tests := []struct {
		name       string
		driver     string
		wantSchema string
		newSource  func(config.SourceConfig) (forecastPoller, error)
	}{
		{
			name:       "hourly",
			driver:     "nws_forecast_hourly",
			wantSchema: standards.SchemaRawNWSHourlyForecastV1,
			newSource: func(cfg config.SourceConfig) (forecastPoller, error) {
				return NewHourlyForecastSource(cfg)
			},
		},
		{
			name:       "narrative",
			driver:     "nws_forecast_narrative",
			wantSchema: standards.SchemaRawNWSNarrativeForecastV1,
			newSource: func(cfg config.SourceConfig) (forecastPoller, error) {
				return NewNarrativeForecastSource(cfg)
			},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				_, _ = w.Write([]byte(`{"properties":{"generatedAt":"2026-03-28T12:00:00Z","updateTime":"2026-03-28T11:00:00Z"}}`))
			}))
			defer srv.Close()

			src, err := tt.newSource(forecastSourceConfig(tt.driver, srv.URL))
			if err != nil {
				t.Fatalf("newSource() error = %v", err)
			}
			if ks, ok := src.(interface{ Kinds() []event.Kind }); !ok {
				t.Fatalf("source does not implement Kinds()")
			} else if gotKinds := ks.Kinds(); len(gotKinds) != 1 || gotKinds[0] != event.Kind("forecast") {
				t.Fatalf("Kinds() = %#v, want [forecast]", gotKinds)
			}

			got, err := src.Poll(context.Background())
			if err != nil {
				t.Fatalf("Poll() error = %v", err)
			}
			if len(got) != 1 {
				t.Fatalf("Poll() len = %d, want 1", len(got))
			}
			if got[0].Schema != tt.wantSchema {
				t.Fatalf("Poll() schema = %q, want %q", got[0].Schema, tt.wantSchema)
			}
			if got[0].Kind != event.Kind("forecast") {
				t.Fatalf("Poll() kind = %q, want forecast", got[0].Kind)
			}

			wantEffectiveAt := time.Date(2026, 3, 28, 12, 0, 0, 0, time.UTC)
			if got[0].EffectiveAt == nil || !got[0].EffectiveAt.Equal(wantEffectiveAt) {
				t.Fatalf("Poll() effectiveAt = %v, want %s", got[0].EffectiveAt, wantEffectiveAt)
			}
		})
	}
}

func TestForecastSourcePollEffectiveAtFallbackOrder(t *testing.T) {
	tests := []struct {
		name            string
		body            string
		wantEffectiveAt *time.Time
	}{
		{
			name: "updateTime fallback",
			body: `{"properties":{"updateTime":"2026-03-28T11:00:00Z"}}`,
			wantEffectiveAt: func() *time.Time {
				t := time.Date(2026, 3, 28, 11, 0, 0, 0, time.UTC)
				return &t
			}(),
		},
		{
			name: "updated fallback",
			body: `{"properties":{"updated":"2026-03-28T10:00:00Z"}}`,
			wantEffectiveAt: func() *time.Time {
				t := time.Date(2026, 3, 28, 10, 0, 0, 0, time.UTC)
				return &t
			}(),
		},
		{
			name:            "omitted when metadata lacks timestamps",
			body:            `{"properties":{}}`,
			wantEffectiveAt: nil,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
				_, _ = w.Write([]byte(tt.body))
			}))
			defer srv.Close()

			src, err := NewHourlyForecastSource(forecastSourceConfig("nws_forecast_hourly", srv.URL))
			if err != nil {
				t.Fatalf("NewHourlyForecastSource() error = %v", err)
			}

			got, err := src.Poll(context.Background())
			if err != nil {
				t.Fatalf("Poll() error = %v", err)
			}
			if len(got) != 1 {
				t.Fatalf("Poll() len = %d, want 1", len(got))
			}
			if tt.wantEffectiveAt == nil {
				if got[0].EffectiveAt != nil {
					t.Fatalf("Poll() effectiveAt = %v, want nil", got[0].EffectiveAt)
				}
				return
			}
			if got[0].EffectiveAt == nil || !got[0].EffectiveAt.Equal(*tt.wantEffectiveAt) {
				t.Fatalf("Poll() effectiveAt = %v, want %s", got[0].EffectiveAt, *tt.wantEffectiveAt)
			}
		})
	}
}

func TestForecastSourcePollMetadataDecodeFailureStillEmitsRawEvent(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_, _ = w.Write([]byte(`not-json`))
	}))
	defer srv.Close()

	src, err := NewNarrativeForecastSource(forecastSourceConfig("nws_forecast_narrative", srv.URL))
	if err != nil {
		t.Fatalf("NewNarrativeForecastSource() error = %v", err)
	}

	got, err := src.Poll(context.Background())
	if err != nil {
		t.Fatalf("Poll() error = %v", err)
	}
	if len(got) != 1 {
		t.Fatalf("Poll() len = %d, want 1", len(got))
	}
	if got[0].EffectiveAt != nil {
		t.Fatalf("Poll() effectiveAt = %v, want nil", got[0].EffectiveAt)
	}
	if got[0].Schema != standards.SchemaRawNWSNarrativeForecastV1 {
		t.Fatalf("Poll() schema = %q, want %q", got[0].Schema, standards.SchemaRawNWSNarrativeForecastV1)
	}

	raw, ok := got[0].Payload.(json.RawMessage)
	if !ok {
		t.Fatalf("Poll() payload type = %T, want json.RawMessage", got[0].Payload)
	}
	if string(raw) != "not-json" {
		t.Fatalf("Poll() payload = %q, want %q", string(raw), "not-json")
	}
}

func forecastSourceConfig(driver, url string) config.SourceConfig {
	return config.SourceConfig{
		Name:   "test-forecast-source",
		Driver: driver,
		Mode:   config.SourceModePoll,
		Params: map[string]any{
			"url":        url,
			"user_agent": "test-agent",
		},
	}
}