improv: Separate components & merge plugins binary with launcher service

plugins/src/pulse/plugin.ron

@@ -0,0 +1,6 @@
+(
+    name: "PulseAudio Volume Control",
+    description: "Control PulseAudio devices and volume",
+    bin: (path: "pulse.js"),
+    icon: Name("multimedia-volume-control")
+)

plugins/src/pulse/pulse.js

@@ -0,0 +1,216 @@
+#!/usr/bin/gjs
+
+const { GLib, Gio } = imports.gi;
+
+const STDIN = new Gio.DataInputStream({ base_stream: new Gio.UnixInputStream({ fd: 0 }) })
+const STDOUT = new Gio.DataOutputStream({ base_stream: new Gio.UnixOutputStream({ fd: 1 }) })
+
+/**
+ * @typedef {Object} Sink
+ * @property {number} id
+ * @property {string} description
+ */
+
+/**
+ * @returns {null | Array<Sink>}
+ */
+function pactl_sinks() {
+    try {
+        const resp = async_process(["pactl", "list", "sinks"])
+        if (!resp) return null
+
+        const { proc, stdout } = resp
+
+        let sinks = new Array()
+        let sink = {}
+
+        while (true) {
+            const [bytes] = stdout.read_line(null)
+            if (bytes === null) break
+
+            const line = imports.byteArray.toString(bytes)
+            if (line.startsWith("Sink")) {
+                sink.id = line.substr(6)
+            } else if (line.includes("Description:")) {
+                sink.description = line.split(' ').slice(1).join(' ')
+                sinks.push({ ...sink })
+            }
+        }
+
+        return sinks
+    } catch (e) {
+        log(`error: ${e}`)
+        return null
+    }
+}
+
+class App {
+    constructor() {
+        this.last_query = ""
+        this.shell_only = false
+
+        this.default_selections = [
+            {
+                id: 0,
+                name: "Toggle Mute",
+                description: "Silence and unsilence the default audio sink",
+            },
+
+            {
+                id: 1,
+                name: "Volume Up",
+                description: "Raise volume 5%"
+            },
+
+            {
+                id: 2,
+                name: "Volume Down",
+                description: "Lower volume 5%"
+            }
+        ]
+    }
+
+    query(input) {
+        const selections = filter_selections(this.default_selections, input.toLowerCase());
+        for (const selection of selections) {
+            this.send({ "Append": selection})
+        }
+
+        this.send("Finished")
+    }
+
+    submit(id) {
+        let cmd = null
+
+        let sinks = pactl_sinks()
+
+        switch (id) {
+            case 0:
+                cmd = ["pactl set-sink-mute", "toggle"]
+                break
+            case 1:
+                cmd = ["pactl set-sink-volume", "+5%"]
+                break
+            case 2:
+                cmd = ["pactl set-sink-volume", "-5%"]
+        }
+
+        if (cmd) {
+            try {
+                for (const { id } of sinks) {
+                    GLib.spawn_command_line_async(`${cmd[0]} ${id} ${cmd[1]}`)
+                }
+
+            } catch (e) {
+                log(`session command '${cmd}' failed: ${e}`)
+            }
+        }
+    }
+
+    send(object) {
+        STDOUT.write_bytes(new GLib.Bytes(JSON.stringify(object) + "\n"), null)
+    }
+}
+
+function main() {
+    /** @type {null | ByteArray} */
+    let input_array
+
+    /** @type {string} */
+    let input_str
+
+    /** @type {null | LauncherRequest} */
+    let event
+
+    let app = new App()
+
+    mainloop:
+    while (true) {
+        try {
+            [input_array,] = STDIN.read_line(null)
+        } catch (e) {
+            break
+        }
+
+        input_str = imports.byteArray.toString(input_array)
+        if ((event = parse_event(input_str)) !== null) {
+            if ("Exit" === event) {
+                break mainloop
+            } else if ("Search" in event) {
+                app.query(event.Search)
+            } else if ("Activate" in event) {
+                app.submit(event.Activate)
+            }
+        }
+    }
+}
+
+/**
+ * Parses an IPC event received from STDIN
+ * @param {string} input
+ * @returns {null | LauncherRequest}
+ */
+function parse_event(input) {
+    try {
+        return JSON.parse(input)
+    } catch (e) {
+        log(`Input not valid JSON`)
+        return null
+    }
+}
+
+/**
+ *
+ * @param {Array<string>} argv
+ * @returns {null | Process}
+ */
+function async_process(argv) {
+    const { DataInputStream, SubprocessFlags, SubprocessLauncher } = Gio
+
+    try {
+        const launcher = new SubprocessLauncher({
+            flags: SubprocessFlags.STDIN_PIPE
+                | SubprocessFlags.STDOUT_PIPE
+        })
+
+        const proc = launcher.spawnv(argv)
+        let stdout = new DataInputStream({
+            base_stream: proc.get_stdout_pipe(),
+            close_base_stream: true
+        })
+
+        return { proc, stdout }
+    } catch (e) {
+        log(`failed to spawn process: ${argv}\n\tCaused by: ${e}`)
+        return null
+    }
+}
+
+function filter_selections(initial, input) {
+    if (input.length === 0) return []
+    let selections = initial.map(v => ({ ...v }))
+
+    let remove = new Array()
+    for (let id = 0; id < selections.length; id += 1) {
+        const { name, description } = selections[id]
+        if (name.toLowerCase().includes(input) || description.toLowerCase().includes(input)) continue
+        remove.push(id)
+    }
+
+    for (const id of remove.reverse()) swap_remove(selections, id)
+
+    return selections
+}
+
+/**
+ *
+ * @param {Array<T>} array
+ * @param {number} index
+ * @returns {T | undefined}
+ */
+function swap_remove(array, index) {
+    array[index] = array[array.length - 1];
+    return array.pop();
+}
+
+main()