Work on code to run shells from a kitten with shell integration

tools/tui/shell_integration/api.go

@@ -0,0 +1,71 @@
+// License: GPLv3 Copyright: 2023, Kovid Goyal, <kovid at kovidgoyal.net>
+
+package shell_integration
+
+import (
+	"archive/tar"
+	"fmt"
+	"os"
+	"path/filepath"
+)
+
+var _ = fmt.Print
+
+type integration_setup_func = func(argv []string, env map[string]string) ([]string, map[string]string, error)
+
+func extract_shell_integration_for(shell_name string, dest_dir string) (err error) {
+	d := Data()
+	for _, fname := range d.FilesMatching("shell-integration/" + shell_name + "/") {
+		entry := d[fname]
+		dest := filepath.Join(dest_dir, fname)
+		ddir := filepath.Dir(dest)
+		if err = os.MkdirAll(ddir, 0o755); err != nil {
+			return
+		}
+		switch entry.Metadata.Typeflag {
+		case tar.TypeDir:
+			if err = os.MkdirAll(dest, 0o755); err != nil {
+				return
+			}
+		case tar.TypeSymlink:
+			if err = os.Symlink(entry.Metadata.Linkname, dest); err != nil {
+				return
+			}
+		case tar.TypeReg:
+			if err = os.WriteFile(dest, entry.Data, 0o644); err != nil {
+				return
+			}
+		}
+	}
+	return
+}
+
+func zsh_setup_func(argv []string, env map[string]string) (final_argv []string, final_env map[string]string, err error) {
+	return
+}
+
+func fish_setup_func(argv []string, env map[string]string) (final_argv []string, final_env map[string]string, err error) {
+	return
+}
+
+func bash_setup_func(argv []string, env map[string]string) (final_argv []string, final_env map[string]string, err error) {
+	return
+}
+
+func setup_func_for_shell(shell_name string) integration_setup_func {
+	switch shell_name {
+	case "zsh":
+		return zsh_setup_func
+	case "fish":
+		return fish_setup_func
+	case "bash":
+		return bash_setup_func
+	}
+	return nil
+}
+
+func IsSupportedShell(shell_name string) bool { return setup_func_for_shell(shell_name) != nil }
+
+func Setup(shell_name string, argv []string, env map[string]string) ([]string, map[string]string, error) {
+	return setup_func_for_shell(shell_name)(argv, env)
+}