refactor daemons + mpd + documentation

3 files changed, 159 insertions, 42 deletions

diff --git a/daemons/mpd.c b/daemons/mpd.c
new file mode 100644
index 0000000..f8dbb64
--- /dev/null
+++ b/daemons/mpd.c
@@ -0,0 +1,156 @@
+// mpd — MPD (Music Player Daemon) daemon for bar
+//
+// Connects to MPD via TCP and uses the `idle` command to block until
+// the player state or playlist changes. When it does, posts a Darwin
+// notification. No polling, no special permissions — just a TCP socket.
+//
+// MPD_HOST and MPD_PORT environment variables are respected (same as
+// mpc's convention). Defaults: localhost:6600.
+//
+// Compile:
+//   cc -o bar-mpd daemons/mpd.c
+
+#include <notify.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <netdb.h>
+#include <sys/socket.h>
+#include <errno.h>
+
+static volatile int keep_running = 1;
+
+static void handle_signal(int sig) {
+	(void)sig;
+	keep_running = 0;
+}
+
+// ── MPD helpers ──────────────────────────────────────────────────────
+
+/// Read a line from the MPD socket (up to newline). Returns the number
+/// of bytes read, or -1 on error. The line is null-terminated.
+static int read_line(int fd, char *buf, size_t size) {
+	size_t i = 0;
+	while (i < size - 1) {
+		ssize_t n = read(fd, &buf[i], 1);
+		if (n <= 0) return -1;
+		if (buf[i] == '\n') break;
+		i++;
+	}
+	buf[i] = '\0';
+	return (int)i;
+}
+
+/// Connect to MPD. Returns a socket fd, or -1 on failure.
+static int connect_mpd(const char *host, int port) {
+	struct addrinfo hints = {0}, *ai = NULL;
+	hints.ai_family = AF_UNSPEC;
+	hints.ai_socktype = SOCK_STREAM;
+
+	char port_str[16];
+	snprintf(port_str, sizeof(port_str), "%d", port);
+
+	int err = getaddrinfo(host, port_str, &hints, &ai);
+	if (err) return -1;
+
+	int fd = -1;
+	for (struct addrinfo *rp = ai; rp; rp = rp->ai_next) {
+		fd = socket(rp->ai_family, rp->ai_socktype, rp->ai_protocol);
+		if (fd < 0) continue;
+		if (connect(fd, rp->ai_addr, rp->ai_addrlen) == 0) break;
+		close(fd);
+		fd = -1;
+	}
+	freeaddrinfo(ai);
+
+	if (fd < 0) return -1;
+
+	// Read the MPD greeting line (e.g. "OK MPD 0.23.0")
+	char buf[256];
+	if (read_line(fd, buf, sizeof(buf)) < 0) {
+		close(fd);
+		return -1;
+	}
+
+	return fd;
+}
+
+/// Send a command to MPD and read the response. Returns 0 on success.
+static int mpd_command(int fd, const char *cmd) {
+	char buf[1024];
+	snprintf(buf, sizeof(buf), "%s\n", cmd);
+	ssize_t len = strlen(buf);
+
+	if (write(fd, buf, len) != len) return -1;
+
+	// Read until we see "OK" or "ACK"
+	while (1) {
+		int n = read_line(fd, buf, sizeof(buf));
+		if (n < 0) return -1;
+		if (strcmp(buf, "OK") == 0) return 0;
+		if (strncmp(buf, "ACK", 3) == 0) return -1;
+		// ignore other response lines (e.g. "changed: player")
+	}
+}
+
+// ── Main ─────────────────────────────────────────────────────────────
+
+int main(void) {
+	// Use sigaction so that read() is NOT restarted after a signal
+	// (macOS's signal() enables SA_RESTART by default, which would
+	//  cause the program to ignore Ctrl+C while blocked on read).
+	struct sigaction sa = {0};
+	sa.sa_handler = handle_signal;
+	sigemptyset(&sa.sa_mask);
+	sa.sa_flags = 0;  // no SA_RESTART → read() returns EINTR
+	sigaction(SIGINT, &sa, NULL);
+	sigaction(SIGTERM, &sa, NULL);
+
+	// Read MPD host/port from environment (same convention as mpc)
+	const char *mpd_host = getenv("MPD_HOST");
+	if (!mpd_host || !*mpd_host) mpd_host = "localhost";
+
+	int mpd_port = 6600;
+	const char *port_env = getenv("MPD_PORT");
+	if (port_env && *port_env) mpd_port = atoi(port_env);
+
+	while (keep_running) {
+		int fd = connect_mpd(mpd_host, mpd_port);
+		if (fd < 0) {
+			// MPD not running yet — wait and retry
+			for (int i = 0; i < 10 && keep_running; i++) sleep(1);
+			continue;
+		}
+
+		// Enter idle mode — blocks until something changes
+		while (keep_running) {
+			const char *idle_cmd = "idle player playlist options\n";
+			ssize_t len = strlen(idle_cmd);
+
+			if (write(fd, idle_cmd, len) != len) break;
+
+			// Read response — will block until MPD sends something
+			char buf[256];
+			int n = read_line(fd, buf, sizeof(buf));
+			if (n < 0) break;
+
+			// Drain the rest of the response
+			while (1) {
+				n = read_line(fd, buf, sizeof(buf));
+				if (n < 0) break;
+				if (strcmp(buf, "OK") == 0) break;
+			}
+
+			notify_post("bar.touch.<block-name>");
+		}
+
+		close(fd);
+
+		// Brief pause before reconnecting
+		if (keep_running) sleep(1);
+	}
+
+	return 0;
+}
diff --git a/daemons/volume/house.panini.bar.volumed.plist b/daemons/volume/house.panini.bar.volumed.plist
deleted file mode 100644
index 09e1084..0000000
--- a/daemons/volume/house.panini.bar.volumed.plist
+++ /dev/null
@@ -1,25 +0,0 @@
-<?xml version="1.0" encoding="UTF-8"?>
-<!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
-<plist version="1.0">
-<dict>
-	<key>Label</key>
-	<string>house.panini.bar.volumed</string>
-
-	<key>ProgramArguments</key>
-	<array>
-		<string>/Users/your-username/.local/bin/bar-volumed</string>
-	</array>
-
-	<key>RunAtLoad</key>
-	<true/>
-
-	<key>KeepAlive</key>
-	<true/>
-
-	<key>StandardOutPath</key>
-	<string>/tmp/bar/volumed.log</string>
-
-	<key>StandardErrorPath</key>
-	<string>/tmp/bar/volumed.log</string>
-</dict>
-</plist>
diff --git a/daemons/volume/volumed.c b/daemons/volumed.c
index 3681b60..ca6afa8 100644
--- a/daemons/volume/volumed.c
+++ b/daemons/volumed.c
@@ -1,4 +1,4 @@
-// bar-volumed — volume daemon for bar (no permissions needed)
+// volumed — volume daemon for bar
 //
 // Uses CoreAudio to listen for system volume/mute changes instead of
 // a CGEvent tap, so no Accessibility permission is required.
@@ -6,22 +6,8 @@
 // When the volume changes, it posts a Darwin notification that tells
 // bar to refresh the "volume" block.
 //
-// ── Setup ──
-//
-// 1. Add a volume block to Config (no interval needed):
-//      Block(name: "volume", placement: .right, command: "<your-volume-script>")
-//
-// 2. Compile and run the daemon:
-//      cc -o ~/.local/bin/bar-volumed daemons/volume/volumed.c -framework CoreAudio
-//      ~/.local/bin/bar-volumed &
-//
-// 3. Or install as a luanch agent:
-//      cp daemons/volume/house.panini.bar.volumed.plist ~/Library/LaunchAgents/
-//      # Make sure to update the ProgramArguments with the correct path to the program
-//      launchctl load ~/Library/LaunchAgents/house.panini.bar.volumed.plist
-//
 // Compile:
-//   cc -o bar-volumed daemons/volume/volumed.c -framework CoreAudio
+//   cc -o bar-volumed daemons/volumed.c -framework CoreAudio
 
 #include <CoreAudio/CoreAudio.h>
 #include <notify.h>
@@ -46,7 +32,7 @@ static OSStatus volume_changed(
 	void *context
 ) {
 	(void)object; (void)num_addresses; (void)addresses; (void)context;
-	notify_post("bar.touch.volume");
+	notify_post("bar.touch.<block-name>");
 	return noErr;
 }