1 files changed, 58 insertions, 0 deletions
diff --git a/command.go b/command.go
new file mode 100644
index 0000000..48dece3
--- /dev/null
+++ b/command.go
@@ -0,0 +1,58 @@
+package complete
+
+type Command struct {
+	Sub   map[string]Command
+	Flags map[string]FlagOptions
+}
+
+// options returns all available complete options for the given command
+// args are all except the last command line arguments relevant to the command
+func (c *Command) options(args []string) (options []string, only bool) {
+
+	// remove the first argument, which is the command name
+	args = args[1:]
+
+	// if prev has something that needs to follow it,
+	// it is the most relevant completion
+	if options, ok := c.Flags[last(args)]; ok && options.HasFollow {
+		return options.FollowsOptions, true
+	}
+
+	sub, options, only := c.searchSub(args)
+	if only {
+		return
+	}
+
+	// if no subcommand was entered in any of the args, add the
+	// subcommands as complete options.
+	if sub == "" {
+		options = append(options, c.subCommands()...)
+	}
+
+	// add global available complete options
+	for flag := range c.Flags {
+		options = append(options, flag)
+	}
+
+	return
+}
+
+func (c *Command) searchSub(args []string) (sub string, all []string, only bool) {
+	for i, arg := range args {
+		if cmd, ok := c.Sub[arg]; ok {
+			sub = arg
+			all, only = cmd.options(args[i:])
+			return
+		}
+	}
+	return "", nil, false
+}
+
+func (c *Command) subCommands() []string {
+	subs := make([]string, 0, len(c.Sub))
+	for sub := range c.Sub {
+		subs = append(subs, sub)
+	}
+	return subs
+}
+