add: merge command

2 files changed, 252 insertions, 0 deletions

diff --git a/internal/cli/commands.go b/internal/cli/commands.go
index f66ff62..fc620c6 100644
--- a/internal/cli/commands.go
+++ b/internal/cli/commands.go
@@ -30,6 +30,11 @@ func defaultCommands() []command {
 			run:  runGenerate,
 		},
 		{
+			name: "merge",
+			desc: "Back up the existing server and merge the generated files into it",
+			run:  runMerge,
+		},
+		{
 			name: "help",
 			desc: "Show available commands",
 			run: func(m *model) tea.Cmd {
diff --git a/internal/cli/merge.go b/internal/cli/merge.go
new file mode 100644
index 0000000..fbae597
--- /dev/null
+++ b/internal/cli/merge.go
@@ -0,0 +1,247 @@
+package cli
+
+import (
+	"archive/zip"
+	"bufio"
+	"compress/flate"
+	"io"
+	"io/fs"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"runtime"
+	"time"
+
+	tea "github.com/charmbracelet/bubbletea"
+
+	"github.com/hachem-wtf/benson/internal/config"
+)
+
+func runMerge(m *model) tea.Cmd {
+	m.busy = true
+	ch := make(chan tea.Msg, 256)
+	m.events = ch
+	cfg := m.cfg
+	go mergeWorker(cfg, ch)
+	return tea.Batch(m.spin.Tick, waitForEvent(ch))
+}
+
+func mergeWorker(cfg *config.Config, ch chan<- tea.Msg) {
+	emit := func(s string) { ch <- streamMsg{s} }
+	done := func(s string) { ch <- streamDoneMsg{s} }
+
+	if cfg.ServerLocation == "" || cfg.BackupLocation == "" {
+		done(errorStyle.Render("server_location and backup_location must be set in config."))
+		return
+	}
+	if _, err := os.Stat(serverDir); err != nil {
+		done(errorStyle.Render("No generated files found. Run 'generate' first."))
+		return
+	}
+
+	emit(headingStyle.Render("Merging generated server"))
+
+	if cfg.MergePreCommand != "" {
+		emit(mutedStyle.Render("Running pre-merge command…"))
+		if err := runShellCommand(cfg.MergePreCommand, emit); err != nil {
+			emit(warnStyle.Render("  pre-command exited: " + err.Error()))
+		}
+	}
+
+	if _, err := os.Stat(cfg.ServerLocation); err == nil {
+		emit(mutedStyle.Render("Backing up " + cfg.ServerLocation + "…"))
+		name, err := createBackup(cfg.ServerLocation, cfg.BackupLocation)
+		if err != nil {
+			done(errorStyle.Render("Failed to create backup: " + err.Error()))
+			return
+		}
+		emit("  " + successStyle.Render("✓ ") + name)
+	} else {
+		emit(mutedStyle.Render("Server location doesn't exist, creating it…"))
+		if err := os.MkdirAll(cfg.ServerLocation, 0o755); err != nil {
+			done(errorStyle.Render("Failed to create server location: " + err.Error()))
+			return
+		}
+	}
+
+	emit(mutedStyle.Render("Moving generated files into place…"))
+	entries, err := os.ReadDir(serverDir)
+	if err != nil {
+		done(errorStyle.Render("Failed to read generated directory: " + err.Error()))
+		return
+	}
+	for _, e := range entries {
+		src := filepath.Join(serverDir, e.Name())
+		dst := filepath.Join(cfg.ServerLocation, e.Name())
+
+		os.RemoveAll(dst)
+		if err := movePath(src, dst); err != nil {
+			done(errorStyle.Render("Failed to move " + e.Name() + ": " + err.Error()))
+			return
+		}
+		emit("  " + successStyle.Render("moved ") + e.Name())
+	}
+	os.RemoveAll(serverDir)
+	emit(successStyle.Render("Merge complete."))
+
+	if cfg.MergePostCommand != "" {
+		emit(mutedStyle.Render("Running post-merge command…"))
+		if err := runShellCommand(cfg.MergePostCommand, emit); err != nil {
+			emit(warnStyle.Render("  post-command exited: " + err.Error()))
+		}
+	}
+
+	done("")
+}
+
+func createBackup(sourceDir, backupDir string) (string, error) {
+	if err := os.MkdirAll(backupDir, 0o755); err != nil {
+		return "", err
+	}
+
+	name := "backup_" + time.Now().Format("2006-01-02_15-04-05") + ".zip"
+	f, err := os.Create(filepath.Join(backupDir, name))
+	if err != nil {
+		return "", err
+	}
+	defer f.Close()
+
+	zw := zip.NewWriter(f)
+	zw.RegisterCompressor(zip.Deflate, func(out io.Writer) (io.WriteCloser, error) {
+		return flate.NewWriter(out, flate.BestCompression)
+	})
+
+	walkErr := filepath.WalkDir(sourceDir, func(path string, d fs.DirEntry, err error) error {
+		if err != nil {
+			return err
+		}
+		if d.IsDir() {
+			return nil
+		}
+
+		rel, err := filepath.Rel(sourceDir, path)
+		if err != nil {
+			return err
+		}
+
+		w, err := zw.Create(filepath.ToSlash(rel))
+		if err != nil {
+			return err
+		}
+
+		src, err := os.Open(path)
+		if err != nil {
+			return err
+		}
+		defer src.Close()
+
+		_, err = io.Copy(w, src)
+		return err
+	})
+	if walkErr != nil {
+		zw.Close()
+		return "", walkErr
+	}
+
+	if err := zw.Close(); err != nil {
+		return "", err
+	}
+	return name, nil
+}
+
+func runShellCommand(command string, emit func(string)) error {
+	var cmd *exec.Cmd
+	if runtime.GOOS == "windows" {
+		cmd = exec.Command("cmd", "/C", command)
+	} else {
+		cmd = exec.Command("sh", "-c", command)
+	}
+
+	pr, pw, err := os.Pipe()
+	if err != nil {
+		return err
+	}
+	cmd.Stdout = pw
+	cmd.Stderr = pw
+
+	if err := cmd.Start(); err != nil {
+		pw.Close()
+		return err
+	}
+	pw.Close()
+
+	scanner := bufio.NewScanner(pr)
+	scanner.Buffer(make([]byte, 0, 64*1024), 1024*1024)
+	for scanner.Scan() {
+		emit(mutedStyle.Render("  │ " + scanner.Text()))
+	}
+	return cmd.Wait()
+}
+
+func movePath(src, dst string) error {
+	if err := os.Rename(src, dst); err == nil {
+		return nil
+	}
+
+	info, err := os.Stat(src)
+	if err != nil {
+		return err
+	}
+
+	if info.IsDir() {
+		if err := copyDir(src, dst); err != nil {
+			return err
+		}
+	} else if err := copyFile(src, dst, info.Mode()); err != nil {
+		return err
+	}
+	return os.RemoveAll(src)
+}
+
+func copyDir(src, dst string) error {
+	if err := os.MkdirAll(dst, 0o755); err != nil {
+		return err
+	}
+
+	entries, err := os.ReadDir(src)
+	if err != nil {
+		return err
+	}
+	for _, e := range entries {
+		s := filepath.Join(src, e.Name())
+		d := filepath.Join(dst, e.Name())
+
+		if e.IsDir() {
+			if err := copyDir(s, d); err != nil {
+				return err
+			}
+			continue
+		}
+
+		info, err := e.Info()
+		if err != nil {
+			return err
+		}
+		if err := copyFile(s, d, info.Mode()); err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func copyFile(src, dst string, mode os.FileMode) error {
+	in, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer in.Close()
+
+	out, err := os.OpenFile(dst, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, mode)
+	if err != nil {
+		return err
+	}
+	defer out.Close()
+
+	_, err = io.Copy(out, in)
+	return err
+}