add chorus command

src/lang.zig

@@ -18,6 +18,7 @@ pub const CommandType = enum {
     Eq,
     Phaser,
     Mbeq,
+    Chorus,
 };
 
 pub const Command = struct {
@@ -82,6 +83,19 @@ pub const Command = struct {
 
         return arr.toSliceConst();
     }
+
+    pub fn appendParam(
+        self: *const Command,
+        params: *plugin.ParamList,
+        symbol: []const u8,
+        idx: usize,
+    ) !void {
+        var val = try self.floatArgAt(idx);
+        try params.append(plugin.Param{
+            .sym = symbol,
+            .value = val,
+        });
+    }
 };
 
 pub const CommandList = std.ArrayList(*Command);
@@ -111,6 +125,7 @@ pub const Lang = struct {
         _ = try self.keywords.put("eq", .Eq);
         _ = try self.keywords.put("mbeq", .Mbeq);
         _ = try self.keywords.put("phaser", .Phaser);
+        _ = try self.keywords.put("chorus", .Chorus);
     }
 
     pub fn parse(self: *Lang, data: []const u8) !CommandList {

src/runner.zig

@@ -248,7 +248,19 @@ pub const Runner = struct {
         try image.runPlugin("http://plugin.org.uk/swh-plugins/mbeq", position, params);
     }
 
+    fn chorusCmd(
+        self: *Runner,
+        pos: plugin.Position,
+        params: plugin.ParamList,
+    ) !void {
+        var image = try self.getImage();
+        try image.runPlugin("http://plugin.org.uk/swh-plugins/multivoiceChorus", pos, params);
+    }
+
     fn runCommand(self: *Runner, cmd: *lang.Command) !void {
+        var params = plugin.ParamList.init(self.allocator);
+        defer params.deinit();
+
         return switch (cmd.command) {
             .Noop => {},
             .Load => blk: {
@@ -301,8 +313,21 @@ pub const Runner = struct {
                 try self.mbeqCmd(pos, bands);
             },
 
+            .Chorus => blk: {
+                const pos = try cmd.consumePosition();
+
+                try cmd.appendParam(&params, "voices", 2);
+                try cmd.appendParam(&params, "delay_base", 3);
+                try cmd.appendParam(&params, "voice_spread", 4);
+                try cmd.appendParam(&params, "detune", 5);
+                try cmd.appendParam(&params, "law_freq", 6);
+                try cmd.appendParam(&params, "attendb", 7);
+
+                try self.chorusCmd(pos, params);
+            },
+
             else => blk: {
-                std.debug.warn("Unknown command: {}\n", cmd.command);
+                std.debug.warn("Unsupported command: {}\n", cmd.command);
                 break :blk RunError.UnknownCommand;
             },
         };