Add night checking and clean up Makefile

Makefile

@@ -18,7 +18,9 @@ install-macos:
 
 # Build for the host system
 build:
-	go build -o build/$(BINARY_NAME) .
+	export CGO_CPPFLAGS="$(pkg-config --cflags opencv4)"
+	export CGO_LDFLAGS="$(pkg-config --libs opencv4 | sed 's/-lopencv_hdf//g' | sed 's/-lopencv_viz//g')"
+	go build -tags customenv -o build/$(BINARY_NAME) .
 
 # Cross-compile for macOS ARM64
 build-macos-arm64:

go.mod

@@ -8,6 +8,7 @@ require (
 	github.com/dustin/go-humanize v1.0.1 // indirect
 	github.com/google/uuid v1.6.0 // indirect
 	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/nathan-osman/go-sunrise v1.1.0 // indirect
 	github.com/ncruces/go-strftime v0.1.9 // indirect
 	github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec // indirect
 	golang.org/x/exp v0.0.0-20250620022241-b7579e27df2b // indirect

go.sum

@@ -4,6 +4,8 @@ github.com/google/uuid v1.6.0 h1:NIvaJDMOsjHA8n1jAhLSgzrAzy1Hgr+hNrb57e+94F0=
 github.com/google/uuid v1.6.0/go.mod h1:TIyPZe4MgqvfeYDBFedMoGGpEw/LqOeaOT+nhxU+yHo=
 github.com/mattn/go-isatty v0.0.20 h1:xfD0iDuEKnDkl03q4limB+vH+GxLEtL/jb4xVJSWWEY=
 github.com/mattn/go-isatty v0.0.20/go.mod h1:W+V8PltTTMOvKvAeJH7IuucS94S2C6jfK/D7dTCTo3Y=
+github.com/nathan-osman/go-sunrise v1.1.0 h1:ZqZmtmtzs8Os/DGQYi0YMHpuUqR/iRoJK+wDO0wTCw8=
+github.com/nathan-osman/go-sunrise v1.1.0/go.mod h1:RcWqhT+5ShCZDev79GuWLayetpJp78RSjSWxiDowmlM=
 github.com/ncruces/go-strftime v0.1.9 h1:bY0MQC28UADQmHmaF5dgpLmImcShSi2kHU9XLdhx/f4=
 github.com/ncruces/go-strftime v0.1.9/go.mod h1:Fwc5htZGVVkseilnfgOVb9mKy6w1naJmn9CehxcKcls=
 github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec h1:W09IVJc94icq4NjY3clb7Lk8O1qJ8BdBEF8z0ibU0rE=

main.go

@@ -11,6 +11,7 @@ import (
 	"strconv"
 	"sync"
 	"time"
+	"github.com/nathan-osman/go-sunrise"
 
 	_ "modernc.org/sqlite"
 	"gocv.io/x/gocv"
@@ -41,6 +42,12 @@ var (
 	lock sync.Mutex
 )
 
+func isNight(lat, lon float64) bool {
+	now := time.Now()
+	sunriseTime, sunsetTime := sunrise.SunriseSunset(lat, lon, now.Year(), now.Month(), now.Day())
+        return now.Before(sunriseTime) || now.After(sunsetTime)
+}
+
 func main() {
 	initDB()
 	go backgroundCollector()
@@ -108,14 +115,22 @@ func estimateCloudCover(url string) (float64, error) {
 }
 
 func backgroundCollector() {
+	lat, lon := 44.3897, -68.8040 // your location (New York example)
 	for {
 		cover, err := estimateCloudCover(imageURL)
 		result := CloudResult{Timestamp: time.Now(), CloudCover: cover}
 		if err != nil {
 			result.Error = err.Error()
 		}
-		storeResult(result)
+
-		fmt.Printf("[%s] Cloud cover: %.2f%%\n", result.Timestamp.Format("15:04:05"), result.CloudCover)
+
+                //lat, lon := 40.7128, -74.0060 // your location (New York example)
+	        if !isNight(lat, lon) {
+		    storeResult(result)
+		    fmt.Printf("[%s] Cloud cover: %.2f%%\n", result.Timestamp.Format("15:04:05"), result.CloudCover)
+                } else {
+	            fmt.Println("🌙 It's night — skipping cloud capture")
+		}
 		time.Sleep(time.Duration(refreshSecs) * time.Second)
 	}
 }