Add installer and startup update prompt

README.md

@@ -21,38 +21,22 @@ A neon-themed terminal dashboard that polls GitHub via the local `gh` CLI and sh
 
 ## Requirements
 
-- Go 1.25+ to build
 - [`gh`](https://cli.github.com/) CLI installed and authenticated (`gh auth login`)
+- Go 1.25+ only if building from source
 
 ## Install
 
-### From a release
+### Linux / macOS
 
-Pre-built binaries for Linux, macOS, and Windows are published on the [Releases](https://github.com/bluegardenproject/github-butler/releases) page. Grab the asset for your platform, mark it executable, and drop it on `$PATH`:
+Install the latest release with one command:
 
 ```bash
-curl -L -o github-butler https://github.com/bluegardenproject/github-butler/releases/latest/download/github-butler-darwin-arm64
-chmod +x github-butler
-mv github-butler /usr/local/bin/
+curl -fsSL https://raw.githubusercontent.com/bluegardenproject/github-butler/main/scripts/install.sh | bash
 ```
 
-(Replace `darwin-arm64` with `linux-amd64`, `linux-arm64`, `darwin-amd64`, or `windows-amd64.exe` as appropriate.)
+The installer downloads the matching release asset into `~/.github-butler/` and adds that directory to your shell `PATH` if needed.
 
-### From source
-
-Clone the repo and build a local binary:
-
-```bash
-git clone https://github.com/bluegardenproject/github-butler.git
-cd github-butler
-make build
-```
-
-Or install straight into `$GOBIN` (usually `~/go/bin`):
-
-```bash
-go install github.com/bluegardenproject/github-butler@latest
-```
+Pre-built binaries are also published on the [Releases](https://github.com/bluegardenproject/github-butler/releases) page.
 
 Verify with `github-butler --version`.
 
@@ -71,6 +55,14 @@ Then run the binary:
 github-butler
 ```
 
+If a newer release is available, `github-butler` prompts before opening the dashboard:
+
+```text
+There is a new version v0.3.0 available. Update now Y/N
+```
+
+Answer `Y` to rerun the same install script, replace the local binary, and restart `github-butler` automatically. Answer `N` to continue with the current version.
+
 ### First launch
 
 On the very first run there's no config file yet, so the dashboard opens empty. Add repos from inside the app:
@@ -176,6 +168,7 @@ cmd/root.go                # flag parsing + wiring, including --version
 internal/
   config/                  # YAML load/save/validate, defaults
   github/                  # gh CLI wrapper, GraphQL query, pure derivation logic
+  update/                  # latest-release check and install-script self-update
   ui/
     app.go                 # root Bubble Tea model + screen routing
     messages.go            # shared tea.Msg types
@@ -188,6 +181,8 @@ internal/
     settings.go            # settings list + interval editor
     theme/                 # neon palette, styles, gradient helper
     components/            # small reusable widgets (banner, countdown, toast, confirm)
+scripts/
+  install.sh               # curl | bash release installer
 ```
 
 ## Development

cmd/root.go

@@ -60,6 +60,12 @@ func Run(ctx context.Context, args []string) error {
 		_ = os.Setenv("NO_COLOR", "1")
 	}
 
+	if updated, err := maybePromptForUpdate(ctx); err != nil {
+		return fmt.Errorf("update github-butler: %w", err)
+	} else if updated {
+		return nil
+	}
+
 	if _, err := exec.LookPath("gh"); err != nil {
 		return fmt.Errorf("the GitHub CLI (`gh`) was not found in PATH; install it and run `gh auth login` first")
 	}

cmd/update_prompt.go

@@ -0,0 +1,62 @@
+package cmd
+
+import (
+	"bufio"
+	"context"
+	"fmt"
+	"os"
+	"strings"
+
+	"github.com/bluegardenproject/github-butler/internal/update"
+)
+
+func maybePromptForUpdate(ctx context.Context) (bool, error) {
+	if version == "dev" || version == "unknown" {
+		return false, nil
+	}
+	if os.Getenv("NO_UPDATE_NOTIFIER") != "" {
+		return false, nil
+	}
+	if !update.Supported() {
+		return false, nil
+	}
+	if !isTerminal(os.Stdin) || !isTerminal(os.Stdout) {
+		return false, nil
+	}
+
+	rel, err := update.LatestRelease(ctx)
+	if err != nil {
+		return false, nil
+	}
+	if update.Compare(version, rel.TagName) >= 0 {
+		return false, nil
+	}
+
+	fmt.Fprintf(os.Stdout, "There is a new version %s available. Update now Y/N ", rel.TagName)
+	answer, err := bufio.NewReader(os.Stdin).ReadString('\n')
+	if err != nil {
+		fmt.Fprintln(os.Stdout)
+		return false, nil
+	}
+
+	switch strings.ToLower(strings.TrimSpace(answer)) {
+	case "y", "yes":
+	default:
+		return false, nil
+	}
+
+	fmt.Fprintln(os.Stdout, "Updating github-butler...")
+	if err := update.Run(ctx); err != nil {
+		return true, err
+	}
+	fmt.Fprintf(os.Stdout, "Update complete. Restarting github-butler %s...\n", rel.TagName)
+	if err := update.Restart(os.Args[1:]); err != nil {
+		return true, err
+	}
+	return true, nil
+}
+
+func isTerminal(file *os.File) bool {
+	info, err := file.Stat()
+	return err == nil && (info.Mode()&os.ModeCharDevice) != 0
+}

internal/update/restart_unix.go

@@ -0,0 +1,17 @@
+//go:build !windows
+
+package update
+
+import (
+	"os"
+	"syscall"
+)
+
+// Restart replaces the current process with the installed github-butler binary.
+func Restart(args []string) error {
+	path, err := InstalledBinaryPath()
+	if err != nil {
+		return err
+	}
+	return syscall.Exec(path, append([]string{path}, args...), os.Environ())
+}

internal/update/restart_windows.go

@@ -0,0 +1,10 @@
+//go:build windows
+
+package update
+
+import "errors"
+
+// Restart is unsupported on Windows because the bundled installer is Unix-only.
+func Restart(args []string) error {
+	return errors.New("self-update restart is not supported on Windows")
+}

internal/update/update.go

@@ -0,0 +1,156 @@
+// Package update checks GitHub releases and reruns the installer when the
+// user accepts a self-update prompt.
+package update
+
+import (
+	"context"
+	"encoding/json"
+	"errors"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"strconv"
+	"strings"
+	"time"
+)
+
+// Repo is the GitHub repo queried for releases. Tests may point it at a stub.
+var Repo = "bluegardenproject/github-butler"
+
+// InstallScriptURL is the public one-line installer target.
+const InstallScriptURL = "https://raw.githubusercontent.com/bluegardenproject/github-butler/main/scripts/install.sh"
+
+const (
+	installDirName = ".github-butler"
+	binaryName     = "github-butler"
+)
+
+// Release is the subset of the GitHub releases API payload we need.
+type Release struct {
+	TagName string `json:"tag_name"`
+	Name    string `json:"name"`
+	HTMLURL string `json:"html_url"`
+}
+
+// LatestRelease fetches the latest published release.
+func LatestRelease(ctx context.Context) (*Release, error) {
+	url := fmt.Sprintf("https://api.github.com/repos/%s/releases/latest", Repo)
+
+	reqCtx, cancel := context.WithTimeout(ctx, 5*time.Second)
+	defer cancel()
+
+	req, err := http.NewRequestWithContext(reqCtx, http.MethodGet, url, nil)
+	if err != nil {
+		return nil, fmt.Errorf("build request: %w", err)
+	}
+	req.Header.Set("Accept", "application/vnd.github+json")
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return nil, fmt.Errorf("fetch latest release: %w", err)
+	}
+	defer resp.Body.Close()
+
+	if resp.StatusCode == http.StatusNotFound {
+		return nil, errors.New("no published releases found")
+	}
+	if resp.StatusCode/100 != 2 {
+		body, _ := io.ReadAll(io.LimitReader(resp.Body, 1024))
+		return nil, fmt.Errorf("github api %d: %s", resp.StatusCode, strings.TrimSpace(string(body)))
+	}
+
+	var rel Release
+	if err := json.NewDecoder(resp.Body).Decode(&rel); err != nil {
+		return nil, fmt.Errorf("decode release: %w", err)
+	}
+	return &rel, nil
+}
+
+// Compare returns -1, 0, or +1 like strings.Compare, treating both versions as
+// dot-separated numeric versions. A leading "v" is ignored.
+func Compare(a, b string) int {
+	if a == b {
+		return 0
+	}
+
+	aDev := isDev(a)
+	bDev := isDev(b)
+	switch {
+	case aDev && bDev:
+		return 0
+	case aDev:
+		return -1
+	case bDev:
+		return 1
+	}
+
+	aParts := strings.Split(strings.TrimPrefix(a, "v"), ".")
+	bParts := strings.Split(strings.TrimPrefix(b, "v"), ".")
+
+	n := len(aParts)
+	if len(bParts) > n {
+		n = len(bParts)
+	}
+	for len(aParts) < n {
+		aParts = append(aParts, "0")
+	}
+	for len(bParts) < n {
+		bParts = append(bParts, "0")
+	}
+
+	for i := 0; i < n; i++ {
+		ai, aErr := strconv.Atoi(aParts[i])
+		bi, bErr := strconv.Atoi(bParts[i])
+		if aErr == nil && bErr == nil {
+			switch {
+			case ai < bi:
+				return -1
+			case ai > bi:
+				return 1
+			}
+			continue
+		}
+		if c := strings.Compare(aParts[i], bParts[i]); c != 0 {
+			return c
+		}
+	}
+	return 0
+}
+
+func isDev(v string) bool {
+	v = strings.ToLower(strings.TrimSpace(v))
+	return v == "" || v == "dev" || v == "unknown"
+}
+
+// Supported reports whether the bundled installer can replace the current
+// platform's binary.
+func Supported() bool {
+	return runtime.GOOS != "windows"
+}
+
+// InstalledBinaryPath returns the location written by scripts/install.sh.
+func InstalledBinaryPath() (string, error) {
+	home, err := os.UserHomeDir()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(home, installDirName, binaryName), nil
+}
+
+// Run executes the install script for the current platform.
+func Run(ctx context.Context) error {
+	if !Supported() {
+		return errors.New("self-update is not supported on Windows")
+	}
+
+	cmd := exec.CommandContext(ctx, "bash", "-c",
+		fmt.Sprintf("curl -fsSL %s | bash", InstallScriptURL))
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	cmd.Stdin = os.Stdin
+	return cmd.Run()
+}