diff options
Diffstat (limited to 'v_windows/v/vlib/cli/help.v')
| -rw-r--r-- | v_windows/v/vlib/cli/help.v | 176 |
1 files changed, 176 insertions, 0 deletions
diff --git a/v_windows/v/vlib/cli/help.v b/v_windows/v/vlib/cli/help.v new file mode 100644 index 0000000..f47f90e --- /dev/null +++ b/v_windows/v/vlib/cli/help.v @@ -0,0 +1,176 @@ +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$cmd.description\n' + } + mut abbrev_len := 0 + mut name_len := cli.min_description_indent_len + if cmd.posix_mode { + for flag in cmd.flags { + if flag.abbrev != '' { + abbrev_len = max(abbrev_len, flag.abbrev.len + cli.spacing + 1) // + 1 for '-' in front + } + name_len = max(name_len, abbrev_len + flag.name.len + cli.spacing + 2) // + 2 for '--' in front + } + for command in cmd.commands { + name_len = max(name_len, command.name.len + cli.spacing) + } + } else { + for flag in cmd.flags { + if flag.abbrev != '' { + abbrev_len = max(abbrev_len, flag.abbrev.len + cli.spacing + 1) // + 1 for '-' in front + } + name_len = max(name_len, abbrev_len + flag.name.len + cli.spacing + 1) // + 1 for '-' in front + } + for command in cmd.commands { + name_len = max(name_len, command.name.len + cli.spacing) + } + } + if cmd.flags.len > 0 { + help += '\nFlags:\n' + for flag in cmd.flags { + mut flag_name := '' + prefix := if cmd.posix_mode { '--' } else { '-' } + if flag.abbrev != '' { + abbrev_indent := ' '.repeat(abbrev_len - flag.abbrev.len - 1) // - 1 for '-' in front + flag_name = '-$flag.abbrev$abbrev_indent$prefix$flag.name' + } else { + abbrev_indent := ' '.repeat(abbrev_len) + flag_name = '$abbrev_indent$prefix$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 +} |