3 files changed, 224 insertions, 0 deletions
diff --git a/cmd/install/home.go b/cmd/install/home.go
new file mode 100644
index 0000000..2694e96
--- /dev/null
+++ b/cmd/install/home.go
@@ -0,0 +1,152 @@
+package install
+
+import (
+	"bufio"
+	"errors"
+	"fmt"
+	"io"
+	"io/ioutil"
+	"os"
+	"os/user"
+	"path/filepath"
+)
+
+type home struct{}
+
+func (home) Install(cmd, bin string) error {
+	bashRCFileName, err := bashRCFileName()
+	if err != nil {
+		return err
+	}
+	completeCmd := completeCmd(cmd, bin)
+	if isInFile(bashRCFileName, completeCmd) {
+		return errors.New("Already installed in ~/.bashrc")
+	}
+
+	bashRC, err := os.OpenFile(bashRCFileName, os.O_RDWR|os.O_APPEND, 0)
+	if err != nil {
+		return err
+	}
+	defer bashRC.Close()
+	_, err = bashRC.WriteString(fmt.Sprintf("\n%s\n", completeCmd))
+	return err
+}
+
+func (home) Uninstall(cmd, bin string) error {
+	bashRC, err := bashRCFileName()
+	if err != nil {
+		return err
+	}
+	backup := bashRC + ".bck"
+	err = copyFile(bashRC, backup)
+	if err != nil {
+		return err
+	}
+	completeCmd := completeCmd(cmd, bin)
+	if !isInFile(bashRC, completeCmd) {
+		return errors.New("Does not installed in ~/.bashrc")
+	}
+	temp, err := uninstallToTemp(bashRC, completeCmd)
+	if err != nil {
+		return err
+	}
+
+	err = copyFile(temp, bashRC)
+	if err != nil {
+		return err
+	}
+
+	return os.Remove(backup)
+}
+
+func completeCmd(cmd, bin string) string {
+	return fmt.Sprintf("complete -C %s %s", bin, cmd)
+}
+
+func bashRCFileName() (string, error) {
+	u, err := user.Current()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Join(u.HomeDir, ".bashrc"), nil
+}
+
+func isInFile(name string, lookFor string) bool {
+	f, err := os.Open(name)
+	if err != nil {
+		return false
+	}
+	defer f.Close()
+	r := bufio.NewReader(f)
+	prefix := []byte{}
+	for {
+		line, isPrefix, err := r.ReadLine()
+		if err == io.EOF {
+			return false
+		}
+		if err != nil {
+			return false
+		}
+		if isPrefix {
+			prefix = append(prefix, line...)
+			continue
+		}
+		line = append(prefix, line...)
+		if string(line) == lookFor {
+			return true
+		}
+		prefix = prefix[:0]
+	}
+}
+
+func uninstallToTemp(bashRCFileName, completeCmd string) (string, error) {
+	rf, err := os.Open(bashRCFileName)
+	if err != nil {
+		return "", err
+	}
+	defer rf.Close()
+	wf, err := ioutil.TempFile("/tmp", "bashrc-")
+	if err != nil {
+		return "", err
+	}
+	defer wf.Close()
+
+	r := bufio.NewReader(rf)
+	prefix := []byte{}
+	for {
+		line, isPrefix, err := r.ReadLine()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return "", err
+		}
+		if isPrefix {
+			prefix = append(prefix, line...)
+			continue
+		}
+		line = append(prefix, line...)
+		str := string(line)
+		if str == completeCmd {
+			continue
+		}
+		wf.WriteString(str + "\n")
+		prefix = prefix[:0]
+	}
+	return wf.Name(), nil
+}
+
+func copyFile(src string, dst string) error {
+	in, err := os.Open(src)
+	if err != nil {
+		return err
+	}
+	defer in.Close()
+	out, err := os.Create(dst)
+	if err != nil {
+		return err
+	}
+	defer out.Close()
+	_, err = io.Copy(out, in)
+	return err
+}
diff --git a/cmd/install/install.go b/cmd/install/install.go
new file mode 100644
index 0000000..cef11f0
--- /dev/null
+++ b/cmd/install/install.go
@@ -0,0 +1,43 @@
+package install
+
+import (
+	"os"
+	"path/filepath"
+)
+
+type installer interface {
+	Install(cmd, bin string) error
+	Uninstall(cmd, bin string) error
+}
+
+func Install(cmd string, asRoot bool) error {
+	bin, err := getBinaryPath()
+	if err != nil {
+		return err
+	}
+	return getInstaller(asRoot).Install(cmd, bin)
+}
+
+func Uninstall(cmd string, asRoot bool) error {
+	bin, err := getBinaryPath()
+	if err != nil {
+		return err
+	}
+	return getInstaller(asRoot).Uninstall(cmd, bin)
+}
+
+func getInstaller(asRoot bool) installer {
+	if asRoot {
+		return root{}
+	} else {
+		return home{}
+	}
+}
+
+func getBinaryPath() (string, error) {
+	bin, err := os.Executable()
+	if err != nil {
+		return "", err
+	}
+	return filepath.Abs(bin)
+}
diff --git a/cmd/install/root.go b/cmd/install/root.go
new file mode 100644
index 0000000..66e23b3
--- /dev/null
+++ b/cmd/install/root.go
@@ -0,0 +1,29 @@
+package install
+
+import "os"
+
+type root struct{}
+
+func (r root) Install(cmd string, bin string) error {
+	completeLink := getBashCompletionDLink(cmd)
+	err := r.Uninstall(cmd, bin)
+	if err != nil {
+		return err
+	}
+	return os.Symlink(bin, completeLink)
+}
+
+func (root) Uninstall(cmd string, bin string) error {
+	completeLink := getBashCompletionDLink(cmd)
+	if _, err := os.Stat(completeLink); err == nil {
+		err := os.Remove(completeLink)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+func getBashCompletionDLink(cmd string) string {
+	return "/etc/bash_completion.d/" + cmd
+}