add basics of printing under new command structure

src/printer.zig

@@ -1,12 +1,74 @@
 const langs = @import("lang.zig");
 
+pub fn printCommand(cmd: langs.Command, comptime tag: langs.Command.Tag) !void {
+    const CommandStruct = langs.Command.tagToType(tag);
+    const casted = cmd.cast(CommandStruct).?;
+
+    // TODO move this to Tag method?
+    const is_typed = switch (tag) {
+        .noop, .load, .quicksave, .runqs, .rotate => false,
+        else => true,
+    };
+
+    const ctype = typ.command_type;
+    switch (ctype) {
+        .lv2_command => try printLV2Command(casted),
+        .custom_command => try printCustomCommand(casted),
+        else => @panic("TODO support command type"),
+    }
+}
+
 pub fn printList(list: langs.CommandList, stream: var) !void {
     for (list.items) |cmd| {
         const command = @tagName(cmd.tag);
         try stream.print("{}", .{command});
 
-        for (cmd.args.items) |arg| {
-            try stream.print(" {}", .{arg});
+        switch (cmd.tag) {
+            .load => {
+                const load = command.cast(langs.Command.Load).?;
+                try stream.print("{}", .{load.path});
+            },
+            .quicksave => {},
+            .rotate => {
+                const rotate = command.cast(langs.Command.Rotate).?;
+                try stream.print("{} {}", .{ rotate.deg, rotate.bgfill });
+            },
+
+            .amp => try printCommand(cmd, .amp),
+            .rflanger => try printCommand(cmd, .rflanger),
+            .eq => try printCommand(cmd, .eq),
+            .phaser => try printCommand(cmd, .phaser),
+            .mbeq => try printCommand(cmd, .mbeq),
+            .chorus => try printCommand(cmd, .chorus),
+            .pitchscaler => try printCommand(cmd, .pitchscaler),
+            .reverb => try printCommand(cmd, .reverb),
+            .highpass => try printCommand(cmd, .highpass),
+            .delay => try printCommand(cmd, .delay),
+            .vinyl => try printCommand(cmd, .vinyl),
+            .revdelay => try printCommand(cmd, .revdelay),
+            .gate => try printCommand(cmd, .gate),
+            .detune => try printCommand(cmd, .detune),
+            .overdrive => try printCommand(cmd, .overdrive),
+            .degrade => try printCommand(cmd, .degrade),
+            .repsycho => try printCommand(cmd, .repsycho),
+            .talkbox => try printCommand(cmd, .talkbox),
+            .dyncomp => try printCommand(cmd, .dyncomp),
+            .thruzero => try printCommand(cmd, .thruzero),
+            .foverdrive => try printCommand(cmd, .foverdrive),
+            .gverb => try printCommand(cmd, .gverb),
+            .invert => try printCommand(cmd, .invert),
+            .tapedelay => try printCommand(cmd, .tapedelay),
+            .moddelay => try printCommand(cmd, .moddelay),
+            .multichorus => try printCommand(cmd, .multichorus),
+            .saturator => try printCommand(cmd, .saturator),
+            .vintagedelay => try printCommand(cmd, .vintagedelay),
+
+            .noise => try printCommand(cmd, .noise),
+            .wildnoise => try printCommand(cmd, .wildnoise),
+            .write => try printCommand(cmd, .write),
+            .embed => try printCommand(cmd, .embed),
+
+            else => @compileError("unhandled command"),
         }
 
         _ = try stream.write(";\n");