package providers

import (
	"context"
	"fmt"
	"log"
	"net/http"
	"net/url"
	"strconv"
	"time"
)

// WU PWS upload protocol endpoint. :contentReference[oaicite:1]{index=1}
const wuEndpoint = "https://rtupdate.wunderground.com/weatherstation/updateweatherstation.php"

type WundergroundClient struct {
	HTTP *http.Client
}

type WUUpload struct {
	StationID  string
	StationKey string

	// Units required by WU:
	// tempf (F), wind mph, baromin (inHg), rain inches.
	TempC      float64
	Humidity   float64
	WindDirDeg float64
	WindAvgMS  float64
	WindMaxMS  float64
	UVI        float64
	SolarWm2   *float64 // your payload is lux; leave nil unless you add W/m^2 later

	RainLastHourMM float64
	DailyRainMM    float64
	PressureHPA    *float64

	DateUTC string // "now" recommended
}

func (c *WundergroundClient) Upload(ctx context.Context, u WUUpload) (string, error) {
	if c.HTTP == nil {
		c.HTTP = &http.Client{Timeout: 10 * time.Second}
	}

	q := url.Values{}
	q.Set("ID", u.StationID)
	q.Set("PASSWORD", u.StationKey)
	q.Set("action", "updateraw")
	q.Set("dateutc", u.DateUTC) // "now" ok :contentReference[oaicite:2]{index=2}

	// Required-ish observation fields (only set what we have)
	q.Set("tempf", fmt.Sprintf("%.2f", cToF(u.TempC)))
	q.Set("humidity", fmt.Sprintf("%.0f", u.Humidity))

	q.Set("winddir", fmt.Sprintf("%.0f", u.WindDirDeg))
	q.Set("windspeedmph", fmt.Sprintf("%.2f", msToMph(u.WindAvgMS)))
	q.Set("windgustmph", fmt.Sprintf("%.2f", msToMph(u.WindMaxMS)))

	// Rain (inches)
	q.Set("rainin", fmt.Sprintf("%.4f", mmToIn(u.RainLastHourMM)))
	q.Set("dailyrainin", fmt.Sprintf("%.4f", mmToIn(u.DailyRainMM)))

	// UV index
	q.Set("UV", fmt.Sprintf("%.2f", u.UVI))

	// Barometric pressure (inHg)
	if u.PressureHPA != nil {
		q.Set("baromin", fmt.Sprintf("%.4f", hPaToInHg(*u.PressureHPA)))
	}

	// NOTE: your WS90 payload provides light in lux, not W/m^2.
	// WU expects solarradiation in W/m^2, so we omit it unless you add a conversion/actual sensor field.
	if u.SolarWm2 != nil {
		q.Set("solarradiation", fmt.Sprintf("%.2f", *u.SolarWm2))
	}

	// Optional: a software identifier
	q.Set("softwaretype", "go-weatherstation-go")

	// Log sanitized params so it's clear what we're sending.
	safe := url.Values{}
	for k, vals := range q {
		if k == "PASSWORD" {
			continue
		}
		for _, v := range vals {
			safe.Add(k, v)
		}
	}
	log.Printf("wunderground upload params %s", safe.Encode())

	reqURL := wuEndpoint + "?" + q.Encode()
	req, err := http.NewRequestWithContext(ctx, http.MethodGet, reqURL, nil)
	if err != nil {
		return "", err
	}

	resp, err := c.HTTP.Do(req)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()

	// WU typically returns plain text like "success"
	if resp.StatusCode/100 != 2 {
		return "", fmt.Errorf("wunderground upload HTTP %d", resp.StatusCode)
	}

	// Read small body
	buf := make([]byte, 2048)
	n, _ := resp.Body.Read(buf)
	return strconv.Quote(string(buf[:n])), nil
}

func cToF(c float64) float64     { return (c * 9.0 / 5.0) + 32.0 }
func msToMph(ms float64) float64 { return ms * 2.2369362920544 }
func mmToIn(mm float64) float64  { return mm / 25.4 }
func hPaToInHg(hpa float64) float64 {
	return hpa * 0.0295299830714
}