package briefing

import (
	"time"

	"gitea.maximumdirect.net/eric/weatherreporter/internal/module"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/timeutil"
	"gitea.maximumdirect.net/eric/weatherreporter/internal/weatherdata"
)

type NarrativeForecastModule struct {
	Product          string                    `json:"product,omitempty"`
	IssuedAt         time.Time                 `json:"issued_at,omitempty"`
	UpdatedAt        *time.Time                `json:"updated_at,omitempty"`
	SourceLocation   string                    `json:"source_location,omitempty"`
	SourceLocationID string                    `json:"source_location_id,omitempty"`
	Periods          []NarrativeForecastPeriod `json:"periods,omitempty"`
}

type NarrativeForecastPeriod struct {
	Name                              string   `json:"name,omitempty"`
	PeriodBegins                      string   `json:"period_begins,omitempty"`
	PeriodEnds                        string   `json:"period_ends,omitempty"`
	IsDay                             *bool    `json:"is_day,omitempty"`
	TextDescription                   string   `json:"text_description,omitempty"`
	TemperatureC                      *float64 `json:"temperature_c,omitempty"`
	TemperatureF                      *float64 `json:"temperature_f,omitempty"`
	TemperatureCMin                   *float64 `json:"temperature_c_min,omitempty"`
	TemperatureFMin                   *float64 `json:"temperature_f_min,omitempty"`
	TemperatureCMax                   *float64 `json:"temperature_c_max,omitempty"`
	TemperatureFMax                   *float64 `json:"temperature_f_max,omitempty"`
	WindSpeedKmh                      *float64 `json:"wind_speed_kmh,omitempty"`
	WindSpeedMph                      *float64 `json:"wind_speed_mph,omitempty"`
	WindGustKmh                       *float64 `json:"wind_gust_kmh,omitempty"`
	WindGustMph                       *float64 `json:"wind_gust_mph,omitempty"`
	WindDirection                     string   `json:"wind_direction,omitempty"`
	ProbabilityOfPrecipitationPercent *float64 `json:"probability_of_precipitation_percent,omitempty"`
}

func buildNarrativeForecastModule(ctx ModuleContext, _ any) (*module.Output, error) {
	narrative := ctx.Collected.Narrative
	if narrative == nil || len(ctx.Derived.ValidPeriodNarrativePeriods) == 0 {
		return nil, nil
	}
	value := NarrativeForecastModule{
		Product:          narrative.Product,
		IssuedAt:         narrative.IssuedAt,
		UpdatedAt:        copyTime(narrative.UpdatedAt),
		SourceLocation:   narrative.LocationName,
		SourceLocationID: narrative.LocationID,
		Periods:          narrativeForecastPeriods(ctx.Derived.ValidPeriodNarrativePeriods, ctx.Timezone),
	}
	if value.isEmpty() {
		return nil, nil
	}
	return &module.Output{ID: module.NarrativeForecast, StanzaName: "narrative_forecast", Value: value}, nil
}

func narrativeForecastPeriods(periods []weatherdata.ForecastPeriod, timezone string) []NarrativeForecastPeriod {
	out := make([]NarrativeForecastPeriod, 0, len(periods))
	for _, period := range periods {
		validPeriod := timeutil.Period{Start: period.StartTime, End: period.EndTime}
		out = append(out, NarrativeForecastPeriod{
			Name:                              period.Name,
			PeriodBegins:                      friendlyPeriodBeginsLabel(validPeriod, timezone),
			PeriodEnds:                        friendlyPeriodEndsLabel(validPeriod, timezone),
			IsDay:                             copyBool(period.IsDay),
			TextDescription:                   period.TextDescription,
			TemperatureC:                      copyFloat(period.TemperatureC),
			TemperatureF:                      copyFloat(period.TemperatureF),
			TemperatureCMin:                   copyFloat(period.TemperatureCMin),
			TemperatureFMin:                   copyFloat(period.TemperatureFMin),
			TemperatureCMax:                   copyFloat(period.TemperatureCMax),
			TemperatureFMax:                   copyFloat(period.TemperatureFMax),
			WindSpeedKmh:                      copyFloat(period.WindSpeedKmh),
			WindSpeedMph:                      copyFloat(period.WindSpeedMph),
			WindGustKmh:                       copyFloat(period.WindGustKmh),
			WindGustMph:                       copyFloat(period.WindGustMph),
			WindDirection:                     windDirectionLabel(period.WindDirectionDegrees),
			ProbabilityOfPrecipitationPercent: copyFloat(period.ProbabilityOfPrecipitationPercent),
		})
	}
	return out
}

func (v NarrativeForecastModule) isEmpty() bool {
	return v.Product == "" &&
		v.IssuedAt.IsZero() &&
		v.UpdatedAt == nil &&
		v.SourceLocation == "" &&
		v.SourceLocationID == "" &&
		len(v.Periods) == 0
}