Add build and make scripts

.gitignore

@@ -0,0 +1,3 @@
+*.db
+.envrc
+build

Makefile

@@ -0,0 +1,38 @@
+# Makefile
+
+# Project name / binary name
+BINARY_NAME := cloudcover
+
+# Default target
+all: build
+
+# Run go app from CLI
+run:
+	go run .
+
+install-linux:
+	sudo apt install libopencv-dev
+
+install-macos:
+	brew install opencv
+
+# Build for the host system
+build:
+	go build -o build/$(BINARY_NAME) .
+
+# Cross-compile for macOS ARM64
+build-macos-arm64:
+	GOOS=darwin GOARCH=arm64 go build -o build/$(BINARY_NAME)-macos-arm64 .
+
+# Cross-compile for Linux AMD64
+build-linux-amd64:
+	GOOS=linux GOARCH=amd64 go build -o build/$(BINARY_NAME)-linux-amd64 .
+
+# Build all targets
+build-all: build-macos-arm64 build-linux-amd64
+
+# Clean build artifacts
+clean:
+	rm -rf build
+
+.PHONY: all build build-macos-arm64 build-linux-amd64 build-all clean

envrc.example

@@ -1,2 +1,3 @@
 export CLOUD_IMAGE_URL="http://clouds.local:8082/snapshot"
 example CLOUD_REFRESH_SECONDS=60
+export CLOUD_DB_PATH="./clouds.db"

go.mod

@@ -3,3 +3,17 @@ module cloudcover
 go 1.24.4
 
 require gocv.io/x/gocv v0.42.0
+
+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/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
+	golang.org/x/sys v0.36.0 // indirect
+	modernc.org/libc v1.66.10 // indirect
+	modernc.org/mathutil v1.7.1 // indirect
+	modernc.org/memory v1.11.0 // indirect
+	modernc.org/sqlite v1.39.1 // indirect
+)

go.sum

@@ -1,2 +1,25 @@
+github.com/dustin/go-humanize v1.0.1 h1:GzkhY7T5VNhEkwH0PVJgjz+fX1rhBrR7pRT3mDkpeCY=
+github.com/dustin/go-humanize v1.0.1/go.mod h1:Mu1zIs6XwVuF/gI1OepvI0qD18qycQx+mFykh5fBlto=
+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/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=
+github.com/remyoudompheng/bigfft v0.0.0-20230129092748-24d4a6f8daec/go.mod h1:qqbHyh8v60DhA7CoWK5oRCqLrMHRGoxYCSS9EjAz6Eo=
 gocv.io/x/gocv v0.42.0 h1:AAsrFJH2aIsQHukkCovWqj0MCGZleQpVyf5gNVRXjQI=
 gocv.io/x/gocv v0.42.0/go.mod h1:zYdWMj29WAEznM3Y8NsU3A0TRq/wR/cy75jeUypThqU=
+golang.org/x/exp v0.0.0-20250620022241-b7579e27df2b h1:M2rDM6z3Fhozi9O7NWsxAkg/yqS/lQJ6PmkyIV3YP+o=
+golang.org/x/exp v0.0.0-20250620022241-b7579e27df2b/go.mod h1:3//PLf8L/X+8b4vuAfHzxeRUl04Adcb341+IGKfnqS8=
+golang.org/x/sys v0.6.0/go.mod h1:oPkhp1MJrh7nUepCBck5+mAzfO9JrbApNNgaTdGDITg=
+golang.org/x/sys v0.36.0 h1:KVRy2GtZBrk1cBYA7MKu5bEZFxQk4NIDV6RLVcC8o0k=
+golang.org/x/sys v0.36.0/go.mod h1:OgkHotnGiDImocRcuBABYBEXf8A9a87e/uXjp9XT3ks=
+modernc.org/libc v1.66.10 h1:yZkb3YeLx4oynyR+iUsXsybsX4Ubx7MQlSYEw4yj59A=
+modernc.org/libc v1.66.10/go.mod h1:8vGSEwvoUoltr4dlywvHqjtAqHBaw0j1jI7iFBTAr2I=
+modernc.org/mathutil v1.7.1 h1:GCZVGXdaN8gTqB1Mf/usp1Y/hSqgI2vAGGP4jZMCxOU=
+modernc.org/mathutil v1.7.1/go.mod h1:4p5IwJITfppl0G4sUEDtCr4DthTaT47/N3aT6MhfgJg=
+modernc.org/memory v1.11.0 h1:o4QC8aMQzmcwCK3t3Ux/ZHmwFPzE6hf2Y5LbkRs+hbI=
+modernc.org/memory v1.11.0/go.mod h1:/JP4VbVC+K5sU2wZi9bHoq2MAkCnrt2r98UGeSK7Mjw=
+modernc.org/sqlite v1.39.1 h1:H+/wGFzuSCIEVCvXYVHX5RQglwhMOvtHSv+VtidL2r4=
+modernc.org/sqlite v1.39.1/go.mod h1:9fjQZ0mB1LLP0GYrp39oOJXx/I2sxEnZtzCmEQIKvGE=

main.go

@@ -1,6 +1,7 @@
 package main
 
 import (
+	"database/sql"
 	"encoding/json"
 	"fmt"
 	"io"
@@ -11,22 +12,39 @@ import (
 	"sync"
 	"time"
 
+	_ "modernc.org/sqlite" // lightweight pure-Go SQLite driver
 	"gocv.io/x/gocv"
 )
 
 type CloudResult struct {
+	ID         int       `json:"id"`
 	Timestamp  time.Time `json:"timestamp"`
 	CloudCover float64   `json:"cloud_cover"`
 	Error      string    `json:"error,omitempty"`
 }
 
 var (
-	imageURL     = getEnv("CLOUD_IMAGE_URL", "http://clouds.local:8082/snapshot")
+	imageURL    = getEnv("CLOUD_IMAGE_URL", "http://clouds.local:8082/snapshot")
-	refreshSecs  = getEnvInt("CLOUD_REFRESH_SECONDS", 30)
+	refreshSecs = getEnvInt("CLOUD_REFRESH_SECONDS", 30)
-	trendHistory []CloudResult
+	dbPath      = getEnv("CLOUD_DB_PATH", "clouds.db")
-	trendLock    sync.Mutex
+
+	db   *sql.DB
+	lock sync.Mutex
 )
 
+func main() {
+	initDB()
+	go backgroundCollector()
+
+	http.HandleFunc("/", dashboardHandler)
+	http.HandleFunc("/cloudcover", handleLatest)
+	http.HandleFunc("/cloudtrend", handleTrend)
+
+	fmt.Printf("☁️  Cloud cover API started at http://localhost:8080\n")
+	fmt.Printf("🔁 Refresh every %ds | Source: %s | DB: %s\n", refreshSecs, imageURL, dbPath)
+	log.Fatal(http.ListenAndServe(":8080", nil))
+}
+
 func estimateCloudCover(url string) (float64, error) {
 	resp, err := http.Get(url)
 	if err != nil {
@@ -64,7 +82,6 @@ func estimateCloudCover(url string) (float64, error) {
 	defer valMask.Close()
 	defer cloudMask.Close()
 
-	// Low saturation, high brightness = likely clouds
 	gocv.InRangeWithScalar(s, gocv.NewScalar(0, 0, 0, 0), gocv.NewScalar(60, 0, 0, 0), &satMask)
 	gocv.InRangeWithScalar(v, gocv.NewScalar(120, 0, 0, 0), gocv.NewScalar(255, 0, 0, 0), &valMask)
 	gocv.BitwiseAnd(satMask, valMask, &cloudMask)
@@ -88,64 +105,96 @@ func backgroundCollector() {
 			result.Error = err.Error()
 		}
 
-		trendLock.Lock()
+		storeResult(result)
-		trendHistory = append(trendHistory, result)
-		if len(trendHistory) > 200 {
-			trendHistory = trendHistory[len(trendHistory)-200:]
-		}
-		trendLock.Unlock()
-
 		fmt.Printf("[%s] Cloud cover: %.2f%%\n", result.Timestamp.Format("15:04:05"), result.CloudCover)
 		time.Sleep(time.Duration(refreshSecs) * time.Second)
 	}
 }
 
-func getEnv(key, def string) string {
+func initDB() {
-	if v, ok := os.LookupEnv(key); ok {
+	var err error
-		return v
+	db, err = sql.Open("sqlite", dbPath)
+	if err != nil {
+		log.Fatalf("failed to open database: %v", err)
+	}
+	_, err = db.Exec(`
+		CREATE TABLE IF NOT EXISTS cloud_trend (
+			id INTEGER PRIMARY KEY AUTOINCREMENT,
+			timestamp DATETIME,
+			cloud_cover REAL,
+			error TEXT
+		)
+	`)
+	if err != nil {
+		log.Fatalf("failed to create table: %v", err)
 	}
-	return def
 }
 
-func getEnvInt(key string, def int) int {
+func storeResult(r CloudResult) {
-	if v, ok := os.LookupEnv(key); ok {
+	lock.Lock()
-		if i, err := strconv.Atoi(v); err == nil {
+	defer lock.Unlock()
-			return i
+
+	_, err := db.Exec(`INSERT INTO cloud_trend (timestamp, cloud_cover, error) VALUES (?, ?, ?)`,
+		r.Timestamp.Format(time.RFC3339), r.CloudCover, r.Error)
+	if err != nil {
+		log.Printf("failed to insert record: %v", err)
+	}
+}
+
+func getLatest() (*CloudResult, error) {
+	row := db.QueryRow(`SELECT id, timestamp, cloud_cover, error FROM cloud_trend ORDER BY id DESC LIMIT 1`)
+	var r CloudResult
+	var ts string
+	if err := row.Scan(&r.ID, &ts, &r.CloudCover, &r.Error); err != nil {
+		return nil, err
+	}
+	r.Timestamp, _ = time.Parse(time.RFC3339, ts)
+	return &r, nil
+}
+
+func getAll(limit int) ([]CloudResult, error) {
+	rows, err := db.Query(`SELECT id, timestamp, cloud_cover, error FROM cloud_trend ORDER BY id DESC LIMIT ?`, limit)
+	if err != nil {
+		return nil, err
+	}
+	defer rows.Close()
+
+	var results []CloudResult
+	for rows.Next() {
+		var r CloudResult
+		var ts string
+		if err := rows.Scan(&r.ID, &ts, &r.CloudCover, &r.Error); err != nil {
+			return nil, err
 		}
+		r.Timestamp, _ = time.Parse(time.RFC3339, ts)
+		results = append(results, r)
 	}
-	return def
-}
 
-func main() {
+	// Reverse to chronological order
-	go backgroundCollector()
+	for i, j := 0, len(results)-1; i < j; i, j = i+1, j-1 {
-
+		results[i], results[j] = results[j], results[i]
-	http.HandleFunc("/", dashboardHandler)
+	}
-	http.HandleFunc("/cloudcover", handleLatest)
+	return results, nil
-	http.HandleFunc("/cloudtrend", handleTrend)
-
-	fmt.Printf("☁️ Cloud cover API started at http://localhost:8080\n")
-	fmt.Printf("🔁 Refresh interval: %ds | Source: %s\n", refreshSecs, imageURL)
-	log.Fatal(http.ListenAndServe(":8080", nil))
 }
 
 func handleLatest(w http.ResponseWriter, r *http.Request) {
-	trendLock.Lock()
+	result, err := getLatest()
-	defer trendLock.Unlock()
+	if err != nil {
-
+		http.Error(w, "no data yet", http.StatusServiceUnavailable)
-	if len(trendHistory) == 0 {
-		http.Error(w, "No data collected yet", http.StatusServiceUnavailable)
 		return
 	}
-	latest := trendHistory[len(trendHistory)-1]
 	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(latest)
+	json.NewEncoder(w).Encode(result)
 }
 
 func handleTrend(w http.ResponseWriter, r *http.Request) {
-	trendLock.Lock()
+	results, err := getAll(200)
-	defer trendLock.Unlock()
+	if err != nil {
+		http.Error(w, err.Error(), 500)
+		return
+	}
 	w.Header().Set("Content-Type", "application/json")
-	json.NewEncoder(w).Encode(trendHistory)
+	json.NewEncoder(w).Encode(results)
 }
 
 func dashboardHandler(w http.ResponseWriter, r *http.Request) {
@@ -163,7 +212,7 @@ func dashboardHandler(w http.ResponseWriter, r *http.Request) {
 </head>
 <body>
   <h1>☁️ Cloud Cover Trend</h1>
-  <p>Live view of sky cloudiness from <code>` + imageURL + `</code></p>
+  <p>Source: <code>` + imageURL + `</code></p>
   <canvas id="chart" width="800" height="400"></canvas>
 
   <script>
@@ -209,3 +258,19 @@ func dashboardHandler(w http.ResponseWriter, r *http.Request) {
 	w.Header().Set("Content-Type", "text/html")
 	w.Write([]byte(html))
 }
+
+func getEnv(key, def string) string {
+	if v, ok := os.LookupEnv(key); ok {
+		return v
+	}
+	return def
+}
+
+func getEnvInt(key string, def int) int {
+	if v, ok := os.LookupEnv(key); ok {
+		if i, err := strconv.Atoi(v); err == nil {
+			return i
+		}
+	}
+	return def
+}