Add infobar autocomplete

cmd/micro/buffer/autocomplete.go

@@ -0,0 +1,82 @@
+package buffer
+
+import (
+	"bytes"
+	"io/ioutil"
+	"os"
+	"strings"
+	"unicode/utf8"
+
+	"github.com/zyedidia/micro/cmd/micro/util"
+)
+
+type Completer func(*Buffer) (string, []string)
+
+func (b *Buffer) GetSuggestions() {
+
+}
+
+func (b *Buffer) Autocomplete(c Completer) {
+
+}
+
+// FileComplete autocompletes filenames
+func FileComplete(b *Buffer) (string, []string) {
+	c := b.GetActiveCursor()
+	l := b.LineBytes(c.Y)
+	l = util.SliceStart(l, c.X)
+
+	args := bytes.Split(l, []byte{' '})
+	input := string(args[len(args)-1])
+	argstart := 0
+	for i, a := range args {
+		if i == len(args)-1 {
+			break
+		}
+		argstart += utf8.RuneCount(a) + 1
+	}
+
+	sep := string(os.PathSeparator)
+	dirs := strings.Split(input, sep)
+
+	var files []os.FileInfo
+	var err error
+	if len(dirs) > 1 {
+		directories := strings.Join(dirs[:len(dirs)-1], sep) + sep
+
+		directories, _ = util.ReplaceHome(directories)
+		files, err = ioutil.ReadDir(directories)
+	} else {
+		files, err = ioutil.ReadDir(".")
+	}
+
+	var suggestions []string
+	if err != nil {
+		return "", suggestions
+	}
+	for _, f := range files {
+		name := f.Name()
+		if f.IsDir() {
+			name += sep
+		}
+		if strings.HasPrefix(name, dirs[len(dirs)-1]) {
+			suggestions = append(suggestions, name)
+		}
+	}
+
+	var chosen string
+	if len(suggestions) == 1 {
+		if len(dirs) > 1 {
+			chosen = strings.Join(dirs[:len(dirs)-1], sep) + sep + suggestions[0]
+		} else {
+			chosen = suggestions[0]
+		}
+	} else {
+		if len(dirs) > 1 {
+			chosen = strings.Join(dirs[:len(dirs)-1], sep) + sep
+		}
+	}
+	chosen = util.SliceEndStr(chosen, c.X-argstart)
+
+	return chosen, suggestions
+}