Fix crash when scrolling too far up

It mostly just looked weird when the underline wasn't on the last row.

CMakeLists.txt

@@ -10,6 +10,14 @@ endif ()
 # For custom modules
 set (CMAKE_MODULE_PATH ${PROJECT_SOURCE_DIR}/liberty/cmake)
 
+# Collect important build toggles for our simple preprocessor
+# (cpp(1) isn't part of POSIX, otherwise we could reuse config.h)
+set (options)
+macro (add_option variable help value)
+	option (${ARGV})
+	list (APPEND options "${variable}=$<BOOL:${${variable}}>")
+endmacro ()
+
 # Dependencies
 find_package (Ncursesw REQUIRED)
 find_package (PkgConfig REQUIRED)
@@ -19,8 +27,8 @@ pkg_check_modules (curl REQUIRED libcurl)
 include (AddThreads)
 
 find_package (Termo QUIET NO_MODULE)
-option (USE_SYSTEM_TERMO
-	"Don't compile our own termo library, use the system one" ${Termo_FOUND})
+add_option (USE_SYSTEM_TERMO
+	"Don't compile our own termo library, use the system one" "${Termo_FOUND}")
 if (USE_SYSTEM_TERMO)
 	if (NOT Termo_FOUND)
 		message (FATAL_ERROR "System termo library not found")
@@ -41,7 +49,8 @@ else ()
 endif ()
 
 pkg_check_modules (fftw fftw3 fftw3f)
-option (WITH_FFTW "Use FFTW to enable spectrum visualisation" ${fftw_FOUND})
+add_option (WITH_FFTW
+	"Use FFTW to enable spectrum visualisation" "${fftw_FOUND}")
 if (WITH_FFTW)
 	if (NOT fftw_FOUND)
 		message (FATAL_ERROR "FFTW not found")
@@ -50,7 +59,8 @@ if (WITH_FFTW)
 endif ()
 
 pkg_check_modules (libpulse libpulse)
-option (WITH_PULSE "Enable control of PulseAudio sink volume" ${libpulse_FOUND})
+add_option (WITH_PULSE
+	"Enable PulseAudio sink volume control" "${libpulse_FOUND}")
 if (WITH_PULSE)
 	if (NOT libpulse_FOUND)
 		message (FATAL_ERROR "libpulse not found")
@@ -59,7 +69,7 @@ if (WITH_PULSE)
 endif ()
 
 pkg_check_modules (x11 x11 xrender xft fontconfig)
-option (WITH_X11 "Use FFTW to enable spectrum visualisation" ${x11_FOUND})
+add_option (WITH_X11 "Use FFTW to enable spectrum visualisation" "${x11_FOUND}")
 if (WITH_X11)
 	if (NOT x11_FOUND)
 		message (FATAL_ERROR "Some X11 libraries were not found")
@@ -95,24 +105,18 @@ foreach (extra m)
 endforeach ()
 
 # Generate a configuration file
+include (GNUInstallDirs)
 configure_file (${PROJECT_SOURCE_DIR}/config.h.in
 	${PROJECT_BINARY_DIR}/config.h)
 include_directories (${PROJECT_SOURCE_DIR} ${PROJECT_BINARY_DIR})
 
-# Assuming a Unix-compatible system with a standalone preprocessor
 set (actions_list ${PROJECT_SOURCE_DIR}/nncmpp.actions)
+set (actions_awk ${PROJECT_SOURCE_DIR}/nncmpp.actions.awk)
 set (actions ${PROJECT_BINARY_DIR}/nncmpp-actions.h)
 add_custom_command (OUTPUT ${actions}
-	COMMAND cpp -I${PROJECT_BINARY_DIR} -P ${actions_list}
-		| grep . | tr [[\n]] ^ | sed -ne [[h; s/,[^^]*/,/g]] -e [[s/$/COUNT/]]
-			-e [[s/[^^]*/\tACTION_&/g]] -e [[s/.*/enum action {\n&\n};\n/p]]
-			-e [[g; s/,[^^]*//g; y/_/-/]] -e [[s/[^^]\{1,\}/\t"&",/g]]
-			-e [[s/.*/static const char *g_action_names[] = {\n&};\n/p]]
-			-e [[g; s/[^^]*, *//g;]] -e [[s/[^^]\{1,\}/\t"&",/g]]
-			-e [[s/.*/static const char *g_action_descriptions[] = {\n&};/p]]
-		| tr ^ [[\n]] > ${actions}
-	COMMAND test -s ${actions}
-	DEPENDS ${actions_list} ${PROJECT_BINARY_DIR}/config.h VERBATIM)
+	COMMAND env LC_ALL=C ${options}
+		awk -f ${actions_awk} ${actions_list} > ${actions}
+	DEPENDS ${actions_awk} ${actions_list} VERBATIM)
 
 # Build the main executable and link it
 add_executable (${PROJECT_NAME} ${PROJECT_NAME}.c ${actions})
@@ -121,16 +125,17 @@ target_link_libraries (${PROJECT_NAME} ${Unistring_LIBRARIES}
 add_threads (${PROJECT_NAME})
 
 # Installation
-include (GNUInstallDirs)
 install (TARGETS ${PROJECT_NAME} DESTINATION ${CMAKE_INSTALL_BINDIR})
 install (FILES LICENSE DESTINATION ${CMAKE_INSTALL_DOCDIR})
 install (DIRECTORY contrib DESTINATION ${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME})
+install (DIRECTORY info DESTINATION ${CMAKE_INSTALL_DATADIR}/${PROJECT_NAME})
 
 # Generate documentation from text markup
 find_program (ASCIIDOCTOR_EXECUTABLE asciidoctor)
 find_program (A2X_EXECUTABLE a2x)
 if (NOT ASCIIDOCTOR_EXECUTABLE AND NOT A2X_EXECUTABLE)
-	message (FATAL_ERROR "Neither asciidoctor nor a2x were found")
+	message (WARNING "Neither asciidoctor nor a2x were found, "
+		"falling back to a substandard manual page generator")
 endif ()
 
 foreach (page ${PROJECT_NAME})
@@ -152,6 +157,14 @@ foreach (page ${PROJECT_NAME})
 				"${PROJECT_SOURCE_DIR}/${page}.adoc"
 			DEPENDS ${page}.adoc
 			COMMENT "Generating man page for ${page}" VERBATIM)
+	else ()
+		set (ASCIIMAN ${PROJECT_SOURCE_DIR}/liberty/tools/asciiman.awk)
+		add_custom_command (OUTPUT ${page_output}
+			COMMAND env LC_ALL=C asciidoc-release-version=${PROJECT_VERSION}
+				awk -f ${ASCIIMAN} "${PROJECT_SOURCE_DIR}/${page}.adoc"
+				> ${page_output}
+			DEPENDS ${page}.adoc ${ASCIIMAN}
+			COMMENT "Generating man page for ${page}" VERBATIM)
 	endif ()
 endforeach ()
 

LICENSE

@@ -1,4 +1,4 @@
-Copyright (c) 2016 - 2022, Přemysl Eric Janouch <p@janouch.name>
+Copyright (c) 2016 - 2023, Přemysl Eric Janouch <p@janouch.name>
 
 Permission to use, copy, modify, and/or distribute this software for any
 purpose with or without fee is hereby granted.

NEWS

@@ -1,3 +1,23 @@
+Unreleased
+
+ * Added ability to look up song lyrics,
+   using a new scriptable extension interface for the Info tab
+
+ * Improved song information shown in the window header
+
+ * Escape no longer quits the program
+
+ * X11: added support for font fallbacks and italic fonts
+
+ * X11: fixed rendering of overflowing, partially visible list items
+
+ * Added a "o" binding to select the currently playing song
+
+ * Added Readline-like M-u, M-l, M-c editor bindings
+
+ * Changed volume adjustment bindings to use +/- keys
+
+
 2.0.0 (2022-09-03)
 
  * Added an optional X11 user interface

README.adoc

@@ -18,6 +18,7 @@ Features
 Most stuff is there.  I've been using the program exclusively for many years.
 Among other things, it can display and change PulseAudio volume directly
 to cover the use case of remote control, it has a fast spectrum visualiser,
+it can be extended with plugins to fetch lyrics or other song-related info,
 and both its appearance and key bindings can be customized.
 
 Note that currently only the filesystem browsing mode is implemented,
@@ -37,10 +38,10 @@ The rest of this README will concern itself with externalities.
 
 Building
 --------
-Build dependencies: CMake, pkg-config, asciidoctor or asciidoc,
-                    liberty (included), termo (included) +
+Build dependencies: CMake, pkg-config, awk, liberty (included),
+ termo (included), asciidoctor or asciidoc (recommended but optional) +
 Runtime dependencies: ncursesw, libunistring, cURL +
-Optional runtime dependencies: fftw3, libpulse, x11, xft
+Optional runtime dependencies: fftw3, libpulse, x11, xft, Perl + cURL (lyrics)
 
  $ git clone --recursive https://git.janouch.name/p/nncmpp.git
  $ mkdir nncmpp/build

config.h.in

@@ -4,6 +4,9 @@
 #define PROGRAM_NAME "${PROJECT_NAME}"
 #define PROGRAM_VERSION "${PROJECT_VERSION}"
 
+// We use the XDG Base Directory Specification, but may be installed anywhere.
+#define PROJECT_DATADIR "${CMAKE_INSTALL_FULL_DATADIR}"
+
 #cmakedefine HAVE_RESIZETERM
 #cmakedefine WITH_FFTW
 #cmakedefine WITH_PULSE

info/10-azlyrics.pl

@@ -0,0 +1,43 @@
+#!/usr/bin/env perl
+# 10-azlyrics.pl: nncmpp info plugin to fetch song lyrics on AZLyrics
+#
+# Copyright (c) 2022, Přemysl Eric Janouch <p@janouch.name>
+# SPDX-License-Identifier: 0BSD
+#
+# Inspired by a similar ncmpc plugin.
+
+use warnings;
+use strict;
+use utf8;
+use open ':std', ':utf8';
+unless (@ARGV) {
+	print "Look up on AZLyrics\n";
+	exit;
+}
+
+use Encode;
+my ($title, $artist, $album) = map {decode_utf8($_)} @ARGV;
+
+# TODO: An upgrade would be transliteration with, e.g., Text::Unidecode.
+use Unicode::Normalize;
+$artist = lc(NFD($artist)) =~ s/^the\s+//ir =~ s/[^a-z0-9]//gr;
+$title  = lc(NFD($title))  =~ s/\(.*?\)//gr =~ s/[^a-z0-9]//gr;
+
+# TODO: Consider caching the results in a location like
+# $XDG_CACHE_HOME/nncmpp/info/azlyrics/$artist-$title
+my $found = 0;
+if ($title ne '') {
+	open(my $curl, '-|', 'curl', '-sA', 'nncmpp/2.0',
+		"https://www.azlyrics.com/lyrics/$artist/$title.html") or die $!;
+	while (<$curl>) {
+		next unless /^<div>/ .. /^<\/div>/; s/<!--.*?-->//g; s/\s+$//gs;
+
+		$found = 1;
+		s/<\/?b>/\x01/g; s/<\/?i>/\x02/g; s/<br>/\n/; s/<.+?>//g;
+		s/&lt;/</g; s/&gt;/>/g; s/&quot;/"/g; s/&apos;/'/g; s/&amp;/&/g;
+		print;
+	}
+	close($curl) or die $?;
+}
+
+print "No lyrics have been found.\n" unless $found;

line-editor.c

@@ -1,7 +1,7 @@
 /*
  * line-editor.c: a line editor component for the TUI part of liberty
  *
- * Copyright (c) 2017 - 2018, Přemysl Eric Janouch <p@janouch.name>
+ * Copyright (c) 2017 - 2022, Přemysl Eric Janouch <p@janouch.name>
  *
  * Permission to use, copy, modify, and/or distribute this software for any
  * purpose with or without fee is hereby granted.
@@ -48,6 +48,10 @@ enum line_editor_action
 	LINE_EDITOR_HOME,                   ///< Go to start of line
 	LINE_EDITOR_END,                    ///< Go to end of line
 
+	LINE_EDITOR_UPCASE_WORD,            ///< Convert word to uppercase
+	LINE_EDITOR_DOWNCASE_WORD,          ///< Convert word to lowercase
+	LINE_EDITOR_CAPITALIZE_WORD,        ///< Capitalize word
+
 	LINE_EDITOR_B_DELETE,               ///< Delete last character
 	LINE_EDITOR_F_DELETE,               ///< Delete next character
 	LINE_EDITOR_B_KILL_WORD,            ///< Delete last word
@@ -185,8 +189,8 @@ line_editor_action (struct line_editor *self, enum line_editor_action action)
 		if (self->point + 1 > (int) self->len)
 			return false;
 		int i = self->point;
-		while (i < (int) self->len && self->line[i] != ' ') i++;
 		while (i < (int) self->len && self->line[i] == ' ') i++;
+		while (i < (int) self->len && self->line[i] != ' ') i++;
 		self->point = i;
 		return true;
 	}
@@ -197,6 +201,41 @@ line_editor_action (struct line_editor *self, enum line_editor_action action)
 		self->point = self->len;
 		return true;
 
+	case LINE_EDITOR_UPCASE_WORD:
+	{
+		int i = self->point;
+		for (; i < (int) self->len && self->line[i] == ' '; i++);
+		for (; i < (int) self->len && self->line[i] != ' '; i++)
+			self->line[i] = uc_toupper (self->line[i]);
+		self->point = i;
+		line_editor_changed (self);
+		return true;
+	}
+	case LINE_EDITOR_DOWNCASE_WORD:
+	{
+		int i = self->point;
+		for (; i < (int) self->len && self->line[i] == ' '; i++);
+		for (; i < (int) self->len && self->line[i] != ' '; i++)
+			self->line[i] = uc_tolower (self->line[i]);
+		self->point = i;
+		line_editor_changed (self);
+		return true;
+	}
+	case LINE_EDITOR_CAPITALIZE_WORD:
+	{
+		int i = self->point;
+		ucs4_t (*converter) (ucs4_t) = uc_totitle;
+		for (; i < (int) self->len && self->line[i] == ' '; i++);
+		for (; i < (int) self->len && self->line[i] != ' '; i++)
+		{
+			self->line[i] = converter (self->line[i]);
+			converter = uc_tolower;
+		}
+		self->point = i;
+		line_editor_changed (self);
+		return true;
+	}
+
 	case LINE_EDITOR_B_DELETE:
 	{
 		if (self->point < 1)

nncmpp.actions

@@ -1,9 +1,8 @@
-#include "config.h"
-
 NONE,               Do nothing
 
 QUIT,               Quit
 REDRAW,             Redraw screen
+ABORT,              Abort
 TAB_HELP,           Switch to help tab
 TAB_LAST,           Switch to last tab
 TAB_PREVIOUS,       Switch to previous tab
@@ -28,11 +27,11 @@ MPD_CONSUME,        Toggle consume
 MPD_UPDATE_DB,      Update MPD database
 MPD_COMMAND,        Send raw command to MPD
 
-#ifdef WITH_PULSE
+.ifdef WITH_PULSE
 PULSE_VOLUME_UP,    Increase PulseAudio volume
 PULSE_VOLUME_DOWN,  Decrease PulseAudio volume
 PULSE_MUTE,         Toggle PulseAudio sink mute
-#endif
+.endif
 
 CHOOSE,             Choose item
 DELETE,             Delete item
@@ -47,6 +46,8 @@ CENTER_CURSOR,      Center the cursor
 MOVE_UP,            Move selection up
 MOVE_DOWN,          Move selection down
 
+GOTO_PLAYING,       Go to playing song
+
 GOTO_TOP,           Go to top
 GOTO_BOTTOM,        Go to bottom
 GOTO_ITEM_PREVIOUS, Go to previous item
@@ -67,6 +68,10 @@ EDITOR_F_WORD,      Go forward a word
 EDITOR_HOME,        Go to start of line
 EDITOR_END,         Go to end of line
 
+EDITOR_UPCASE_WORD,     Convert word to uppercase
+EDITOR_DOWNCASE_WORD,   Convert word to lowercase
+EDITOR_CAPITALIZE_WORD, Capitalize word
+
 EDITOR_B_DELETE,    Delete last character
 EDITOR_F_DELETE,    Delete next character
 EDITOR_B_KILL_WORD, Delete last word

nncmpp.actions.awk

@@ -0,0 +1,106 @@
+# nncmpp.actions.awk: produce C code for a list of user actions
+#
+# Copyright (c) 2022, Přemysl Eric Janouch <p@janouch.name>
+# SPDX-License-Identifier: 0BSD
+#
+# Usage: env LC_ALL=C A=0 B=1 awk -f nncmpp.actions.awk \
+#  nncmpp.actions > nncmpp-actions.h
+
+# --- Preprocessor -------------------------------------------------------------
+
+function fatal(message) {
+	print "// " FILENAME ":" FNR ": fatal error: " message
+	print FILENAME ":" FNR ": fatal error: " message > "/dev/stderr"
+	exit 1
+}
+
+function condition(pass,    passing, a, i) {
+	split(substr($0, RSTART + RLENGTH), a, /[[:space:]]+/)
+	if (!(1 in a))
+		fatal("missing condition")
+
+	passing = 0
+	for (i in a)
+		if (a[i] && !pass == !ENVIRON[a[i]])
+			passing = 1
+
+	while (getline > 0) {
+		if (match($0, /^[[:space:]]*[.]endif[[:space:]]*$/))
+			return 1
+
+		if (match($0, /^[[:space:]]*[.]else[[:space:]]*$/))
+			passing = !passing
+		else if (!directive() && passing)
+			process()
+	}
+
+	fatal("unterminated condition body")
+}
+
+# Multiple arguments mean logical OR, multiple directives mean logical AND.
+# Similar syntax is also used by Exim, BSD make, or various assemblers.
+#
+# Looking at what others have picked for their preprocessor syntax:
+# {OpenGL, FreeBASIC} reuse #ifdef, which would be confusing with C code around,
+# {Mental Ray, RapidQ and UniVerse BASIC} use $ifdef, NSIS has !ifdef,
+# and Verilog went for `ifdef.  Not much more can be easily found.
+function directive() {
+	sub(/#.*/, "")
+	if (match($0, /^[[:space:]]*[.]ifdef[[:space:]]+/))
+		return condition(1)
+	if (match($0, /^[[:space:]]*[.]ifndef[[:space:]]+/))
+		return condition(0)
+	if (/^[[:space:]]*[.]/)
+		fatal("unexpected or unsupported directive")
+	return 0
+}
+
+!directive() {
+	process()
+}
+
+# --- Postprocessor ------------------------------------------------------------
+
+function strip(string) {
+	gsub(/^[[:space:]]*|[[:space:]]*$/, "", string)
+	return string
+}
+
+function process(    constant, name, description) {
+	if (match($0, /,/)) {
+		constant = name = strip(substr($0, 1, RSTART - 1))
+		description = strip(substr($0, RSTART + RLENGTH))
+		gsub(/_/, "-", name)
+
+		N++
+		Constants[N] = constant
+		Names[N] = tolower(name)
+		Descriptions[N] = description
+	} else if (/[^[:space:]]/) {
+		fatal("invalid action definition syntax")
+	}
+}
+
+function tocstring(string) {
+	gsub(/\\/, "\\\\", string)
+	gsub(/"/, "\\\"", string)
+	return "\"" string "\""
+}
+
+END {
+	print "enum action {"
+	for (i in Constants)
+		print "\t" "ACTION_" Constants[i] ","
+	print "\t" "ACTION_COUNT"
+	print "};"
+	print ""
+	print "static const char *g_action_names[] = {"
+	for (i in Names)
+		print "\t" tocstring(Names[i]) ","
+	print "};"
+	print ""
+	print "static const char *g_action_descriptions[] = {"
+	for (i in Descriptions)
+		print "\t" tocstring(Descriptions[i]) ","
+	print "};"
+}

nncmpp.adoc

@@ -81,6 +81,10 @@ The distribution contains example colour schemes in the _contrib_ directory.
 // TODO: it seems like liberty should contain an includable snippet about
 //   the format, which could form a part of nncmpp.conf(5).
 
+To adjust key bindings, put them within a *normal* or *editor* object.
+Run *nncmpp* with the *--debug* option to find out key combinations names.
+Press *?* in the help tab to learn the action identifiers to use.
+
 Spectrum visualiser
 -------------------
 When built against the FFTW library, *nncmpp* can make use of MPD's "fifo"
@@ -113,8 +117,8 @@ as in the snippet above.  To replace the default volume control bindings, use:
 
 ....
 normal = {
-  "M-PageUp" = "pulse-volume-up"
-  "M-PageDown" = "pulse-volume-down"
+  "+" = "pulse-volume-up"
+  "-" = "pulse-volume-down"
 }
 ....
 
@@ -124,6 +128,19 @@ For this to work, *nncmpp* needs to access the right PulseAudio daemon--in case
 your setup is unusual, consult the list of environment variables in
 *pulseaudio*(1).  MPD-compatibles are currently unsupported.
 
+Info plugins
+------------
+You can invoke various plugins from the Info tab, for example to look up
+song lyrics.
+
+Plugins can be arbitrary scripts or binaries.  When run without command line
+arguments, a plugin outputs a user interface description of what it does.
+When invoked by a user, it receives the following self-explanatory arguments:
+_TITLE_ _ARTIST_ [_ALBUM_], and anything it writes to its standard output
+or standard error stream is presented back to the user.  Here, bold and italic
+formatting can be toggled with ASCII control characters 1 (SOH) and 2 (STX),
+respectively.  Otherwise, all input and output makes use of the UTF-8 encoding.
+
 Files
 -----
 *nncmpp* follows the XDG Base Directory Specification.
@@ -131,6 +148,14 @@ Files
 _~/.config/nncmpp/nncmpp.conf_::
 	The configuration file.
 
+_~/.local/share/nncmpp/info/_::
+_/usr/local/share/nncmpp/info/_::
+_/usr/share/nncmpp/info/_::
+	Info plugins are loaded from these directories, in order,
+	then listed lexicographically.
+	Only the first occurence of a particular filename is used,
+	and empty files act as silent disablers.
+
 Reporting bugs
 --------------
 Use https://git.janouch.name/p/nncmpp to report bugs, request features,