1// Copyright 2010 The Kyua Authors.
2// All rights reserved.
3//
4// Redistribution and use in source and binary forms, with or without
5// modification, are permitted provided that the following conditions are
6// met:
7//
8// * Redistributions of source code must retain the above copyright
9//   notice, this list of conditions and the following disclaimer.
10// * Redistributions in binary form must reproduce the above copyright
11//   notice, this list of conditions and the following disclaimer in the
12//   documentation and/or other materials provided with the distribution.
13// * Neither the name of Google Inc. nor the names of its contributors
14//   may be used to endorse or promote products derived from this software
15//   without specific prior written permission.
16//
17// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
18// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
19// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
20// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
21// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
22// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
23// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
24// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
28
29#include "cli/cmd_help.hpp"
30
31#include <algorithm>
32#include <cstdlib>
33
34#include "cli/common.ipp"
35#include "utils/cmdline/commands_map.ipp"
36#include "utils/cmdline/exceptions.hpp"
37#include "utils/cmdline/globals.hpp"
38#include "utils/cmdline/options.hpp"
39#include "utils/cmdline/parser.hpp"
40#include "utils/cmdline/ui.hpp"
41#include "utils/defs.hpp"
42#include "utils/format/macros.hpp"
43#include "utils/sanity.hpp"
44#include "utils/text/table.hpp"
45
46namespace cmdline = utils::cmdline;
47namespace config = utils::config;
48namespace text = utils::text;
49
50using cli::cmd_help;
51
52
53namespace {
54
55
56/// Creates a table with the help of a set of options.
57///
58/// \param options The set of options to describe.  May be empty.
59///
60/// \return A 2-column wide table with the description of the options.
61static text::table
62options_help(const cmdline::options_vector& options)
63{
64    text::table table(2);
65
66    for (cmdline::options_vector::const_iterator iter = options.begin();
67         iter != options.end(); iter++) {
68        const cmdline::base_option* option = *iter;
69
70        std::string description = option->description();
71        if (option->needs_arg() && option->has_default_value())
72            description += F(" (default: %s)") % option->default_value();
73
74        text::table_row row;
75
76        if (option->has_short_name())
77            row.push_back(F("%s, %s") % option->format_short_name() %
78                          option->format_long_name());
79        else
80            row.push_back(F("%s") % option->format_long_name());
81        row.push_back(F("%s.") % description);
82
83        table.add_row(row);
84    }
85
86    return table;
87}
88
89
90/// Prints the summary of commands and generic options.
91///
92/// \param ui Object to interact with the I/O of the program.
93/// \param options The set of program-wide options for which to print help.
94/// \param commands The set of commands for which to print help.
95static void
96general_help(cmdline::ui* ui, const cmdline::options_vector* options,
97             const cmdline::commands_map< cli::cli_command >* commands)
98{
99    PRE(!commands->empty());
100
101    cli::write_version_header(ui);
102    ui->out("");
103    ui->out_tag_wrap(
104        "Usage: ",
105        F("%s [general_options] command [command_options] [args]") %
106        cmdline::progname(), false);
107
108    const text::table options_table = options_help(*options);
109    text::widths_vector::value_type first_width =
110        options_table.column_width(0);
111
112    std::map< std::string, text::table > command_tables;
113
114    for (cmdline::commands_map< cli::cli_command >::const_iterator
115         iter = commands->begin(); iter != commands->end(); iter++) {
116        const std::string& category = (*iter).first;
117        const std::set< std::string >& command_names = (*iter).second;
118
119        command_tables.insert(std::map< std::string, text::table >::value_type(
120            category, text::table(2)));
121        text::table& table = command_tables.find(category)->second;
122
123        for (std::set< std::string >::const_iterator i2 = command_names.begin();
124             i2 != command_names.end(); i2++) {
125            const cli::cli_command* command = commands->find(*i2);
126            text::table_row row;
127            row.push_back(command->name());
128            row.push_back(F("%s.") % command->short_description());
129            table.add_row(row);
130        }
131
132        if (table.column_width(0) > first_width)
133            first_width = table.column_width(0);
134    }
135
136    text::table_formatter formatter;
137    formatter.set_column_width(0, first_width);
138    formatter.set_column_width(1, text::table_formatter::width_refill);
139    formatter.set_separator("  ");
140
141    if (!options_table.empty()) {
142        ui->out_wrap("");
143        ui->out_wrap("Available general options:");
144        ui->out_table(options_table, formatter, "  ");
145    }
146
147    // Iterate using the same loop as above to preserve ordering.
148    for (cmdline::commands_map< cli::cli_command >::const_iterator
149         iter = commands->begin(); iter != commands->end(); iter++) {
150        const std::string& category = (*iter).first;
151        ui->out_wrap("");
152        ui->out_wrap(F("%s commands:") %
153                (category.empty() ? "Generic" : category));
154        ui->out_table(command_tables.find(category)->second, formatter, "  ");
155    }
156
157    ui->out_wrap("");
158    ui->out_wrap("See kyua(1) for more details.");
159}
160
161
162/// Prints help for a particular subcommand.
163///
164/// \param ui Object to interact with the I/O of the program.
165/// \param general_options The options that apply to all commands.
166/// \param command Pointer to the command to describe.
167static void
168subcommand_help(cmdline::ui* ui,
169                const utils::cmdline::options_vector* general_options,
170                const cli::cli_command* command)
171{
172    cli::write_version_header(ui);
173    ui->out("");
174    ui->out_tag_wrap(
175        "Usage: ", F("%s [general_options] %s%s%s") %
176        cmdline::progname() % command->name() %
177        (command->options().empty() ? "" : " [command_options]") %
178        (command->arg_list().empty() ? "" : (" " + command->arg_list())),
179        false);
180    ui->out_wrap("");
181    ui->out_wrap(F("%s.") % command->short_description());
182
183    const text::table general_table = options_help(*general_options);
184    const text::table command_table = options_help(command->options());
185
186    const text::widths_vector::value_type first_width =
187        std::max(general_table.column_width(0), command_table.column_width(0));
188    text::table_formatter formatter;
189    formatter.set_column_width(0, first_width);
190    formatter.set_column_width(1, text::table_formatter::width_refill);
191    formatter.set_separator("  ");
192
193    if (!general_table.empty()) {
194        ui->out_wrap("");
195        ui->out_wrap("Available general options:");
196        ui->out_table(general_table, formatter, "  ");
197    }
198
199    if (!command_table.empty()) {
200        ui->out_wrap("");
201        ui->out_wrap("Available command options:");
202        ui->out_table(command_table, formatter, "  ");
203    }
204
205    ui->out_wrap("");
206    ui->out_wrap(F("See kyua-%s(1) for more details.") % command->name());
207}
208
209
210}  // anonymous namespace
211
212
213/// Default constructor for cmd_help.
214///
215/// \param options_ The set of program-wide options for which to provide help.
216/// \param commands_ The set of commands for which to provide help.
217cmd_help::cmd_help(const cmdline::options_vector* options_,
218                   const cmdline::commands_map< cli_command >* commands_) :
219    cli_command("help", "[subcommand]", 0, 1, "Shows usage information"),
220    _options(options_),
221    _commands(commands_)
222{
223}
224
225
226/// Entry point for the "help" subcommand.
227///
228/// \param ui Object to interact with the I/O of the program.
229/// \param cmdline Representation of the command line to the subcommand.
230///
231/// \return 0 to indicate success.
232int
233cmd_help::run(utils::cmdline::ui* ui, const cmdline::parsed_cmdline& cmdline,
234              const config::tree& /* user_config */)
235{
236    if (cmdline.arguments().empty()) {
237        general_help(ui, _options, _commands);
238    } else {
239        INV(cmdline.arguments().size() == 1);
240        const std::string& cmdname = cmdline.arguments()[0];
241        const cli::cli_command* command = _commands->find(cmdname);
242        if (command == NULL)
243            throw cmdline::usage_error(F("The command %s does not exist") %
244                                       cmdname);
245        else
246            subcommand_help(ui, _options, command);
247    }
248
249    return EXIT_SUCCESS;
250}
251