Refactor into packages

.gitignore

@@ -1,2 +1,2 @@
-dl
+/dl
 *.part*

Makefile

@@ -24,7 +24,7 @@ all: help
 .PHONY: build
 build:
 	@echo "Building $(BINARY_NAME)..."
-	@$(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME) .
+	@$(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME) ./cmd/dl
 
 # Build for all platforms
 .PHONY: build-all
@@ -34,21 +34,21 @@ build-all: build-linux build-darwin build-windows
 .PHONY: build-linux
 build-linux:
 	@echo "Building for Linux..."
-	@GOOS=linux GOARCH=amd64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-linux-amd64 .
-	@GOOS=linux GOARCH=arm64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-linux-arm64 .
+	@GOOS=linux GOARCH=amd64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-linux-amd64 ./cmd/dl
+	@GOOS=linux GOARCH=arm64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-linux-arm64 ./cmd/dl
 
 # Build for macOS
 .PHONY: build-darwin
 build-darwin:
 	@echo "Building for macOS..."
-	@GOOS=darwin GOARCH=amd64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-darwin-amd64 .
-	@GOOS=darwin GOARCH=arm64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-darwin-arm64 .
+	@GOOS=darwin GOARCH=amd64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-darwin-amd64 ./cmd/dl
+	@GOOS=darwin GOARCH=arm64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-darwin-arm64 ./cmd/dl
 
 # Build for Windows
 .PHONY: build-windows
 build-windows:
 	@echo "Building for Windows..."
-	@GOOS=windows GOARCH=amd64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-windows-amd64.exe .
+	@GOOS=windows GOARCH=amd64 $(GO_BUILD) $(LDFLAGS) -o $(BINARY_NAME)-windows-amd64.exe ./cmd/dl
 
 # Run tests
 .PHONY: test
@@ -101,7 +101,7 @@ clean:
 .PHONY: install
 install:
 	@echo "Installing $(BINARY_NAME)..."
-	@$(GO) install $(LDFLAGS) .
+	@$(GO) install $(LDFLAGS) ./cmd/dl
 	@echo "Installed to $(shell go env GOPATH)/bin/$(BINARY_NAME)"
 	@if ! echo $$PATH | grep -q "$(shell go env GOPATH)/bin"; then \
 		echo ""; \
@@ -136,7 +136,7 @@ test-resume: build
 .PHONY: dev
 dev:
 	@echo "Building with race detector..."
-	@$(GO_BUILD) -race $(LDFLAGS) -o $(BINARY_NAME) .
+	@$(GO_BUILD) -race $(LDFLAGS) -o $(BINARY_NAME) ./cmd/dl
 	@echo "Ready for development testing"
 
 # Show help
@@ -158,4 +158,4 @@ help:
 	@echo "  make test-download  - Test download functionality"
 	@echo "  make test-resume    - Test resume functionality"
 	@echo "  make dev            - Build with race detector for development"
-	@echo "  make help           - Show this help message"
+	@echo "  make help           - Show this help message"

README.md

@@ -24,7 +24,7 @@ Requires Go 1.23+
 ```bash
 git clone https://github.com/mgomes/dl.git
 cd dl
-go build
+go build -o dl ./cmd/dl
 ```
 
 ## Usage
@@ -33,6 +33,44 @@ go build
 dl <url> [url2] [url3] ...
 ```
 
+## Library usage
+
+```go
+package main
+
+import (
+	"context"
+	"fmt"
+	"os"
+
+	"github.com/mgomes/dl"
+)
+
+func main() {
+	ctx := context.Background()
+	downloader := dl.Downloader{
+		URI:        "https://example.com/file.zip",
+		Context:    ctx,
+		WorkingDir: ".",
+		Boost:      4,
+		Retries:    3,
+		Resume:     true,
+	}
+
+	if err := downloader.FetchMetadata(); err != nil {
+		fmt.Printf("metadata error: %v\n", err)
+		os.Exit(1)
+	}
+
+	if err := downloader.Fetch(); err != nil {
+		fmt.Printf("download error: %v\n", err)
+		os.Exit(1)
+	}
+
+	fmt.Println("saved to", downloader.OutputPath())
+}
+```
+
 ### Options
 
 ```

main.go → cmd/dl/main.go

@@ -8,6 +8,8 @@ import (
 	"os"
 	"os/signal"
 	"syscall"
+
+	"github.com/mgomes/dl"
 )
 
 func main() {
@@ -52,54 +54,54 @@ func main() {
 	}()
 
 	for _, uri := range fileURIs {
-		var dl download
-		dl.uri = uri
-		dl.boost = *boostPtr
-		dl.retries = *retriesPtr
-		dl.resume = *resumePtr && !*noResumePtr
-		dl.bandwidthLimit = bandwidthLimit
-		dl.ctx = ctx
-
-		if err := dl.FetchMetadata(); err != nil {
+		downloader := dl.Downloader{
+			URI:            uri,
+			Boost:          *boostPtr,
+			Retries:        *retriesPtr,
+			Resume:         *resumePtr && !*noResumePtr,
+			BandwidthLimit: bandwidthLimit,
+			Context:        ctx,
+		}
+
+		if err := downloader.FetchMetadata(); err != nil {
 			fmt.Fprintf(os.Stderr, "Error fetching metadata for %s: %v\n", uri, err)
 			os.Exit(1)
 		}
 
 		if *filenamePtr != "" {
-			dl.filename = *filenamePtr
+			downloader.Filename = *filenamePtr
 		}
 
 		wd, err := os.Getwd()
 		if err != nil {
 			fmt.Fprintf(os.Stderr, "Error getting working directory: %v\n", err)
 			os.Exit(1)
 		}
-		dl.workingDir = wd
+		downloader.WorkingDir = wd
 
-		fmt.Println("Downloading:", dl.filename)
+		fmt.Println("Downloading:", downloader.Filename)
 
-		if !dl.supportsRange && dl.boost > 1 {
+		if !downloader.SupportsRange() && downloader.Boost > 1 {
 			fmt.Println("Server does not support partial content. Falling back to single-threaded download.")
-			dl.boost = 1
+			downloader.Boost = 1
 		}
 
-		if err := dl.Fetch(); err != nil {
+		downloader.Progress = newProgressBarReporter(downloader.FileSize())
+
+		if err := downloader.Fetch(); err != nil {
 			if errors.Is(err, context.Canceled) {
 				fmt.Println("\nDownload cancelled")
 				os.Exit(1)
 			}
 			fmt.Fprintf(os.Stderr, "Error while downloading: %v\n", err)
-			if dl.progress == nil {
-				_ = os.Remove(dl.outputPath())
-			}
 			os.Exit(1)
 		}
 
-		fmt.Println("Download completed:", dl.filename)
+		fmt.Println("Download completed:", downloader.Filename)
 
 		if *checksumPtr != "" {
 			fmt.Printf("Verifying checksum...")
-			if err := verifyChecksum(dl.outputPath(), *checksumPtr); err != nil {
+			if err := verifyChecksum(downloader.OutputPath(), *checksumPtr); err != nil {
 				fmt.Fprintf(os.Stderr, "\nChecksum verification failed: %v\n", err)
 				os.Exit(1)
 			}

cmd/dl/progress.go

@@ -0,0 +1,42 @@
+package main
+
+import "github.com/schollz/progressbar/v3"
+
+type progressBarReporter struct {
+	bar *progressbar.ProgressBar
+}
+
+func newProgressBarReporter(total uint64) *progressBarReporter {
+	return &progressBarReporter{
+		bar: progressbar.DefaultBytes(int64(total), "Downloading"),
+	}
+}
+
+func (p *progressBarReporter) SetTotal(total uint64) {
+	if p.bar == nil {
+		p.bar = progressbar.DefaultBytes(int64(total), "Downloading")
+		return
+	}
+	p.bar.ChangeMax64(int64(total))
+}
+
+func (p *progressBarReporter) SetDownloaded(downloaded uint64) {
+	if p.bar == nil {
+		return
+	}
+	_ = p.bar.Set64(int64(downloaded))
+}
+
+func (p *progressBarReporter) AddDownloaded(delta uint64) {
+	if p.bar == nil {
+		return
+	}
+	_ = p.bar.Add64(int64(delta))
+}
+
+func (p *progressBarReporter) Done() {
+	if p.bar == nil {
+		return
+	}
+	_ = p.bar.Finish()
+}