fuckery.m

#import "jsobjc.h"
#import "dom.generated.h"
#include <emscripten/emscripten.h>

EM_JS(void, install_demo_interop, (), {
    class BaseGreeter {
        constructor(name) {
            this.name = name;
        }

        print() {
            globalThis.console.log("BaseGreeter:", this.name);
        }
    }

    globalThis.BaseGreeter = BaseGreeter;
    globalThis.doSomething = function(cl) {
        const value = new cl("bob");
        value.print();
        return value.name;
    };
    globalThis.makeJSSubclassInstance = function(cl) {
        class JSGreeter extends cl {
            print() {
                super.print();
                globalThis.console.log("JS subclass:", this.name);
            }
        }

        return new JSGreeter("jane");
    };
    globalThis.useObjCSubclassOfJS = function(cl) {
        const value = new cl("erin");
        value.print();
        return value.name;
    };
});

@class MyClass;
@class ObjCGreeter;

@interface Window (DemoInterop)
- (String *)doSomething:(Class)classValue;
- (MyClass *)makeJSSubclassInstance:(Class)classValue;
- (String *)useObjCSubclassOfJS:(Class)classValue;
@end

@interface Window (DemoCompat)
@property (nonatomic, readonly, strong) XMLHttpRequest *XMLHTTPRequest;
@end

@interface MyClass : JSObject {
    String *_name;
}

@property (nonatomic, readonly, strong) String *name;

+ (instancetype)newWithName:(String *)nm;
- (void)print;
@end

@interface BaseGreeter : JSObject
+ (instancetype)new:(String *)name;
- (String *)name;
- (void)print;
@end

@interface ObjCGreeter : BaseGreeter
- (void)print;
@end

@implementation MyClass
@synthesize name = _name;

+ (instancetype)newWithName:(String *)nm {
    auto instance = [super new];
    instance->_name = nm;
    return instance;
}

- (void)print {
    [js.window.console log:@"Hello, " :_name];
}
@end

@implementation BaseGreeter
@end

@implementation ObjCGreeter
- (void)print {
    [super print];
    [js.window.console log:@"ObjC subclass:" :self.name];
}
@end

@implementation Window (DemoCompat)
- (XMLHttpRequest *)XMLHTTPRequest {
    return self.XMLHttpRequest;
}
@end

int main() {
    install_demo_interop();

    auto window = js.window;
    auto console = window.console;

    [console log:@"hello, world!"];

    auto response = [window fetch: @"./demo/data.json"].await;
    auto data = response.json.await;
    window.document.title = data[@"title"];

    auto request = [js.window.XMLHTTPRequest new];
    [request open:@"GET" url:@"./demo/data.json" async:false];
    [request send];
    [console log:@"xhr response:" :request.responseText];

    auto createdName = [window doSomething:MyClass.class];
    [console log:@"objc class result:" :createdName];
    auto jsSubclassInstance = [window makeJSSubclassInstance:MyClass.class];
    [jsSubclassInstance print];
    [console log:@"js subclass result:" :jsSubclassInstance.name];

    auto objcSubclassClass = ObjCGreeter.class;
    auto objcSubclassName = [window useObjCSubclassOfJS:objcSubclassClass];
    [console log:@"objc subclass of js result:" :objcSubclassName];
    window.document.body.textContent = objcSubclassName;

    return 0;
}