1 files changed, 172 insertions, 0 deletions
diff --git a/v_windows/v/old/vlib/cli/help.v b/v_windows/v/old/vlib/cli/help.v
new file mode 100644
index 0000000..6ce3e41
--- /dev/null
+++ b/v_windows/v/old/vlib/cli/help.v
@@ -0,0 +1,172 @@
+module cli
+
+import term
+import strings
+
+const (
+	base_indent_len            = 2
+	min_description_indent_len = 20
+	spacing                    = 2
+)
+
+fn help_flag(with_abbrev bool) Flag {
+	sabbrev := if with_abbrev { 'h' } else { '' }
+	return Flag{
+		flag: .bool
+		name: 'help'
+		abbrev: sabbrev
+		description: 'Prints help information.'
+	}
+}
+
+fn help_cmd() Command {
+	return Command{
+		name: 'help'
+		usage: '<command>'
+		description: 'Prints help information.'
+		execute: print_help_for_command
+	}
+}
+
+fn print_help_for_command(help_cmd Command) ? {
+	if help_cmd.args.len > 0 {
+		mut cmd := help_cmd.parent
+		for arg in help_cmd.args {
+			mut found := false
+			for sub_cmd in cmd.commands {
+				if sub_cmd.name == arg {
+					cmd = unsafe { &sub_cmd }
+					found = true
+					break
+				}
+			}
+			if !found {
+				args := help_cmd.args.join(' ')
+				println('Invalid command: $args')
+				return
+			}
+		}
+		print(cmd.help_message())
+	} else {
+		if help_cmd.parent != 0 {
+			print(help_cmd.parent.help_message())
+		}
+	}
+}
+
+fn (cmd Command) help_message() string {
+	mut help := ''
+	help += 'Usage: $cmd.full_name()'
+	if cmd.flags.len > 0 {
+		help += ' [flags]'
+	}
+	if cmd.commands.len > 0 {
+		help += ' [commands]'
+	}
+	if cmd.usage.len > 0 {
+		help += ' $cmd.usage'
+	} else {
+		for i in 0 .. cmd.required_args {
+			help += ' <arg$i>'
+		}
+	}
+	help += '\n'
+	if cmd.description != '' {
+		help += '\n$cmd.description\n'
+	}
+	mut abbrev_len := 0
+	mut name_len := cli.min_description_indent_len
+	if cmd.flags.have_abbrev() {
+		for flag in cmd.flags {
+			abbrev_len = max(abbrev_len, flag.abbrev.len + cli.spacing + 1) // + 1 for '-' in front
+			name_len = max(name_len, abbrev_len + flag.name.len + cli.spacing + 2) // + 2 for '--' in front
+		}
+		for command in cmd.commands {
+			name_len = max(name_len, command.name.len + cli.spacing)
+		}
+	} else {
+		for flag in cmd.flags {
+			name_len = max(name_len, abbrev_len + flag.name.len + cli.spacing + 1) // + 1 for '-' in front
+		}
+		for command in cmd.commands {
+			name_len = max(name_len, command.name.len + cli.spacing)
+		}
+	}
+	if cmd.flags.len > 0 {
+		help += '\nFlags:\n'
+		for flag in cmd.flags {
+			mut flag_name := ''
+			if flag.abbrev != '' && cmd.flags.have_abbrev() {
+				abbrev_indent := ' '.repeat(abbrev_len - flag.abbrev.len - 1) // - 1 for '-' in front
+				flag_name = '-$flag.abbrev$abbrev_indent--$flag.name'
+			} else if cmd.flags.have_abbrev() {
+				abbrev_indent := ' '.repeat(abbrev_len)
+				flag_name = '$abbrev_indent--$flag.name'
+			} else {
+				flag_name = '-$flag.name'
+			}
+			mut required := ''
+			if flag.required {
+				required = ' (required)'
+			}
+			base_indent := ' '.repeat(cli.base_indent_len)
+			description_indent := ' '.repeat(name_len - flag_name.len)
+			help += '$base_indent$flag_name$description_indent' +
+				pretty_description(flag.description + required, cli.base_indent_len + name_len) +
+				'\n'
+		}
+	}
+	if cmd.commands.len > 0 {
+		help += '\nCommands:\n'
+		for command in cmd.commands {
+			base_indent := ' '.repeat(cli.base_indent_len)
+			description_indent := ' '.repeat(name_len - command.name.len)
+			help += '$base_indent$command.name$description_indent' +
+				pretty_description(command.description, name_len) + '\n'
+		}
+	}
+	return help
+}
+
+// pretty_description resizes description text depending on terminal width.
+// Essentially, smart wrap-around
+fn pretty_description(s string, indent_len int) string {
+	width, _ := term.get_terminal_size()
+	// Don't prettify if the terminal is that small, it won't be pretty anyway.
+	if indent_len > width {
+		return s
+	}
+	indent := ' '.repeat(indent_len)
+	chars_per_line := width - indent_len
+	// Give us enough room, better a little bigger than smaller
+	mut acc := strings.new_builder(((s.len / chars_per_line) + 1) * (width + 1))
+	for k, line in s.split('\n') {
+		if k != 0 {
+			acc.write_string('\n$indent')
+		}
+		mut i := chars_per_line - 2
+		mut j := 0
+		for ; i < line.len; i += chars_per_line - 2 {
+			for line[i] != ` ` {
+				i--
+			}
+			// indent was already done the first iteration
+			if j != 0 {
+				acc.write_string(indent)
+			}
+			acc.writeln(line[j..i].trim_space())
+			j = i
+		}
+		// We need this even though it should never happen
+		if j != 0 {
+			acc.write_string(indent)
+		}
+		acc.write_string(line[j..].trim_space())
+	}
+	return acc.str()
+}
+
+fn max(a int, b int) int {
+	res := if a > b { a } else { b }
+	return res
+}