package forecasts

import (
	"context"
	"fmt"
	"time"

	"gitea.maximumdirect.net/ejr/weatherapi/internal/application/units"
	"gitea.maximumdirect.net/ejr/weatherapi/internal/core/ports"
	"gitea.maximumdirect.net/ejr/weatherapi/internal/platform/constants"
)

type Service struct {
	repo     ports.ForecastRepository
	registry *units.Registry
	limit    int
}

func NewService(repo ports.ForecastRepository, registry *units.Registry, limit int) *Service {
	return &Service{repo: repo, registry: registry, limit: limit}
}

type Response struct {
	Timestamp time.Time        `json:"timestamp"`
	Periods   []PeriodResponse `json:"periods"`
}

type PeriodResponse struct {
	PeriodIndex                       int       `json:"periodIndex"`
	StartTime                         time.Time `json:"startTime"`
	EndTime                           time.Time `json:"endTime"`
	Name                              *string   `json:"name,omitempty"`
	IsDay                             *bool     `json:"isDay,omitempty"`
	ConditionCode                     int       `json:"conditionCode"`
	ConditionText                     *string   `json:"conditionText,omitempty"`
	ProviderRawDescription            *string   `json:"providerRawDescription,omitempty"`
	TextDescription                   *string   `json:"textDescription,omitempty"`
	DetailedText                      *string   `json:"detailedText,omitempty"`
	IconURL                           *string   `json:"iconUrl,omitempty"`
	TemperatureC                      *float64  `json:"temperatureC,omitempty"`
	TemperatureF                      *float64  `json:"temperatureF,omitempty"`
	TemperatureCMin                   *float64  `json:"temperatureCMin,omitempty"`
	TemperatureFMin                   *float64  `json:"temperatureFMin,omitempty"`
	TemperatureCMax                   *float64  `json:"temperatureCMax,omitempty"`
	TemperatureFMax                   *float64  `json:"temperatureFMax,omitempty"`
	DewpointC                         *float64  `json:"dewpointC,omitempty"`
	DewpointF                         *float64  `json:"dewpointF,omitempty"`
	RelativeHumidityPercent           *float64  `json:"relativeHumidityPercent,omitempty"`
	WindDirectionDegrees              *float64  `json:"windDirectionDegrees,omitempty"`
	WindSpeedKmh                      *float64  `json:"windSpeedKmh,omitempty"`
	WindSpeedMph                      *float64  `json:"windSpeedMph,omitempty"`
	WindGustKmh                       *float64  `json:"windGustKmh,omitempty"`
	WindGustMph                       *float64  `json:"windGustMph,omitempty"`
	BarometricPressurePa              *float64  `json:"barometricPressurePa,omitempty"`
	VisibilityMeters                  *float64  `json:"visibilityMeters,omitempty"`
	ApparentTemperatureC              *float64  `json:"apparentTemperatureC,omitempty"`
	ApparentTemperatureF              *float64  `json:"apparentTemperatureF,omitempty"`
	CloudCoverPercent                 *float64  `json:"cloudCoverPercent,omitempty"`
	ProbabilityOfPrecipitationPercent *float64  `json:"probabilityOfPrecipitationPercent,omitempty"`
	PrecipitationAmountMm             *float64  `json:"precipitationAmountMm,omitempty"`
	SnowfallDepthMm                   *float64  `json:"snowfallDepthMm,omitempty"`
	UVIndex                           *float64  `json:"uvIndex,omitempty"`
}

func (s *Service) GetByTimestamp(ctx context.Context, ts time.Time, unitSystem string) (Response, error) {
	if s == nil {
		return Response{}, fmt.Errorf("forecasts service is nil")
	}

	converter, err := s.registry.Resolve(unitSystem)
	if err != nil {
		return Response{}, err
	}

	periodsMetric, err := s.repo.ListForecastPeriodsAt(ctx, ts, s.limit)
	if err != nil {
		return Response{}, err
	}

	periods := make([]PeriodResponse, 0, len(periodsMetric))
	for _, p := range periodsMetric {
		item := PeriodResponse{
			PeriodIndex:                       p.PeriodIndex,
			StartTime:                         p.StartTime,
			EndTime:                           p.EndTime,
			Name:                              p.Name,
			IsDay:                             p.IsDay,
			ConditionCode:                     p.ConditionCode,
			ConditionText:                     p.ConditionText,
			ProviderRawDescription:            p.ProviderRawDescription,
			TextDescription:                   p.TextDescription,
			DetailedText:                      p.DetailedText,
			IconURL:                           p.IconURL,
			RelativeHumidityPercent:           p.RelativeHumidityPercent,
			WindDirectionDegrees:              p.WindDirectionDegrees,
			BarometricPressurePa:              p.BarometricPressurePa,
			VisibilityMeters:                  p.VisibilityMeters,
			CloudCoverPercent:                 p.CloudCoverPercent,
			ProbabilityOfPrecipitationPercent: p.ProbabilityOfPrecipitationPercent,
			PrecipitationAmountMm:             p.PrecipitationAmountMm,
			SnowfallDepthMm:                   p.SnowfallDepthMm,
			UVIndex:                           p.UVIndex,
		}

		switch converter.System() {
		case constants.UnitSystemUS:
			item.TemperatureF = converter.TemperatureCToOutput(p.TemperatureC)
			item.TemperatureFMin = converter.TemperatureCToOutput(p.TemperatureCMin)
			item.TemperatureFMax = converter.TemperatureCToOutput(p.TemperatureCMax)
			item.DewpointF = converter.TemperatureCToOutput(p.DewpointC)
			item.WindSpeedMph = converter.SpeedKmhToOutput(p.WindSpeedKmh)
			item.WindGustMph = converter.SpeedKmhToOutput(p.WindGustKmh)
			item.ApparentTemperatureF = converter.TemperatureCToOutput(p.ApparentTemperatureC)
		default:
			item.TemperatureC = converter.TemperatureCToOutput(p.TemperatureC)
			item.TemperatureCMin = converter.TemperatureCToOutput(p.TemperatureCMin)
			item.TemperatureCMax = converter.TemperatureCToOutput(p.TemperatureCMax)
			item.DewpointC = converter.TemperatureCToOutput(p.DewpointC)
			item.WindSpeedKmh = converter.SpeedKmhToOutput(p.WindSpeedKmh)
			item.WindGustKmh = converter.SpeedKmhToOutput(p.WindGustKmh)
			item.ApparentTemperatureC = converter.TemperatureCToOutput(p.ApparentTemperatureC)
		}

		periods = append(periods, item)
	}

	return Response{
		Timestamp: ts,
		Periods:   periods,
	}, nil
}