Files
j2s/src/java/me/topchetoeu/jscript/lib/PromiseLib.java

405 lines
14 KiB
Java

package me.topchetoeu.jscript.lib;
import java.util.ArrayList;
import java.util.List;
import me.topchetoeu.jscript.common.ResultRunnable;
import me.topchetoeu.jscript.runtime.Context;
import me.topchetoeu.jscript.runtime.EventLoop;
import me.topchetoeu.jscript.runtime.Extensions;
import me.topchetoeu.jscript.runtime.exceptions.EngineException;
import me.topchetoeu.jscript.runtime.exceptions.InterruptException;
import me.topchetoeu.jscript.runtime.values.ArrayValue;
import me.topchetoeu.jscript.runtime.values.FunctionValue;
import me.topchetoeu.jscript.runtime.values.NativeFunction;
import me.topchetoeu.jscript.runtime.values.ObjectValue;
import me.topchetoeu.jscript.runtime.values.Values;
import me.topchetoeu.jscript.utils.interop.Arguments;
import me.topchetoeu.jscript.utils.interop.Expose;
import me.topchetoeu.jscript.utils.interop.ExposeConstructor;
import me.topchetoeu.jscript.utils.interop.ExposeTarget;
import me.topchetoeu.jscript.utils.interop.WrapperName;
@WrapperName("Promise")
public class PromiseLib {
public static interface Handle {
void onFulfil(Object val);
void onReject(EngineException err);
default Handle defer(Extensions loop) {
var self = this;
return new Handle() {
@Override public void onFulfil(Object val) {
if (!loop.hasNotNull(EventLoop.KEY)) throw EngineException.ofError("No event loop");
loop.get(EventLoop.KEY).pushMsg(() -> self.onFulfil(val), true);
}
@Override public void onReject(EngineException val) {
if (!loop.hasNotNull(EventLoop.KEY)) throw EngineException.ofError("No event loop");
loop.get(EventLoop.KEY).pushMsg(() -> self.onReject(val), true);
}
};
}
}
private static final int STATE_PENDING = 0;
private static final int STATE_FULFILLED = 1;
private static final int STATE_REJECTED = 2;
private List<Handle> handles = new ArrayList<>();
private int state = STATE_PENDING;
private boolean handled = false;
private Object val;
private void resolveSynchronized(Context ctx, Object val, int newState) {
this.val = val;
this.state = newState;
for (var handle : handles) {
if (newState == STATE_FULFILLED) handle.onFulfil(val);
if (newState == STATE_REJECTED) {
handle.onReject((EngineException)val);
handled = true;
}
}
if (state == STATE_REJECTED && !handled) {
Values.printError(((EngineException)val).setExtensions(ctx), "(in promise)");
}
handles = null;
// ctx.get(EventLoop.KEY).pushMsg(() -> {
// if (!ctx.hasNotNull(EventLoop.KEY)) throw EngineException.ofError("No event loop");
// handles = null;
// }, true);
}
private synchronized void resolve(Context ctx, Object val, int newState) {
if (this.state != STATE_PENDING || newState == STATE_PENDING) return;
handle(ctx, val, new Handle() {
@Override public void onFulfil(Object val) {
resolveSynchronized(ctx, val, newState);
}
@Override public void onReject(EngineException err) {
resolveSynchronized(ctx, val, STATE_REJECTED);
}
});
}
public synchronized void fulfill(Context ctx, Object val) {
resolve(ctx, val, STATE_FULFILLED);
}
public synchronized void reject(Context ctx, EngineException val) {
resolve(ctx, val, STATE_REJECTED);
}
private void handle(Handle handle) {
if (state == STATE_FULFILLED) handle.onFulfil(val);
else if (state == STATE_REJECTED) {
handle.onReject((EngineException)val);
handled = true;
}
else handles.add(handle);
}
@Override public String toString() {
if (state == STATE_PENDING) return "Promise (pending)";
else if (state == STATE_FULFILLED) return "Promise (fulfilled)";
else return "Promise (rejected)";
}
public PromiseLib() {
this.state = STATE_PENDING;
this.val = null;
}
public static PromiseLib await(Context ctx, ResultRunnable<Object> runner) {
var res = new PromiseLib();
new Thread(() -> {
try {
res.fulfill(ctx, runner.run());
}
catch (EngineException e) {
res.reject(ctx, e);
}
catch (Exception e) {
if (e instanceof InterruptException) throw e;
else {
res.reject(ctx, EngineException.ofError("Native code failed with " + e.getMessage()));
}
}
}, "Promisifier").start();
return res;
}
public static PromiseLib await(Context ctx, Runnable runner) {
return await(ctx, () -> {
runner.run();
return null;
});
}
public static void handle(Context ctx, Object obj, Handle handle) {
if (Values.isWrapper(obj, PromiseLib.class)) {
var promise = Values.wrapper(obj, PromiseLib.class);
handle(ctx, promise, handle);
return;
}
if (obj instanceof PromiseLib) {
((PromiseLib)obj).handle(handle);
return;
}
var rethrow = new boolean[1];
try {
var then = Values.getMember(ctx, obj, "then");
if (then instanceof FunctionValue) Values.call(ctx, then, obj,
new NativeFunction(args -> {
try { handle.onFulfil(args.get(0)); }
catch (Exception e) {
rethrow[0] = true;
throw e;
}
return null;
}),
new NativeFunction(args -> {
try { handle.onReject(new EngineException(args.get(0))); }
catch (Exception e) {
rethrow[0] = true;
throw e;
}
return null;
})
);
else handle.onFulfil(obj);
return;
}
catch (Exception e) {
if (rethrow[0]) throw e;
}
handle.onFulfil(obj);
}
public static PromiseLib ofResolved(Context ctx, Object value) {
var res = new PromiseLib();
res.fulfill(ctx, value);
return res;
}
public static PromiseLib ofRejected(Context ctx, EngineException value) {
var res = new PromiseLib();
res.reject(ctx, value);
return res;
}
@Expose(value = "resolve", target = ExposeTarget.STATIC)
public static PromiseLib __ofResolved(Arguments args) {
return ofResolved(args.ctx, args.get(0));
}
@Expose(value = "reject", target = ExposeTarget.STATIC)
public static PromiseLib __ofRejected(Arguments args) {
return ofRejected(args.ctx, new EngineException(args.get(0)).setExtensions(args.ctx));
}
@Expose(target = ExposeTarget.STATIC)
public static PromiseLib __any(Arguments args) {
if (!(args.get(0) instanceof ArrayValue)) throw EngineException.ofType("Expected argument for any to be an array.");
var promises = args.convert(0, ArrayValue.class);
if (promises.size() == 0) return ofRejected(args.ctx, EngineException.ofError("No promises passed to 'Promise.any'.").setExtensions(args.ctx));
var n = new int[] { promises.size() };
var res = new PromiseLib();
var errors = new ArrayValue();
for (var i = 0; i < promises.size(); i++) {
var index = i;
var val = promises.get(i);
if (res.state != STATE_PENDING) break;
handle(args.ctx, val, new Handle() {
public void onFulfil(Object val) { res.fulfill(args.ctx, val); }
public void onReject(EngineException err) {
errors.set(args.ctx, index, err.value);
n[0]--;
if (n[0] <= 0) res.reject(args.ctx, new EngineException(errors).setExtensions(args.ctx));
}
});
}
return res;
}
@Expose(target = ExposeTarget.STATIC)
public static PromiseLib __race(Arguments args) {
if (!(args.get(0) instanceof ArrayValue)) throw EngineException.ofType("Expected argument for any to be an array.");
var promises = args.convert(0, ArrayValue.class);
var res = new PromiseLib();
for (var i = 0; i < promises.size(); i++) {
var val = promises.get(i);
if (res.state != STATE_PENDING) break;
handle(args.ctx, val, new Handle() {
@Override public void onFulfil(Object val) { res.fulfill(args.ctx, val); }
@Override public void onReject(EngineException err) { res.reject(args.ctx, err); }
});
}
return res;
}
@Expose(target = ExposeTarget.STATIC)
public static PromiseLib __all(Arguments args) {
if (!(args.get(0) instanceof ArrayValue)) throw EngineException.ofType("Expected argument for any to be an array.");
var promises = args.convert(0, ArrayValue.class);
var n = new int[] { promises.size() };
var res = new PromiseLib();
var result = new ArrayValue();
for (var i = 0; i < promises.size(); i++) {
if (res.state != STATE_PENDING) break;
var index = i;
var val = promises.get(i);
handle(args.ctx, val, new Handle() {
@Override public void onFulfil(Object val) {
result.set(args.ctx, index, val);
n[0]--;
if (n[0] <= 0) res.fulfill(args.ctx, result);
}
@Override public void onReject(EngineException err) {
res.reject(args.ctx, err);
}
});
}
if (n[0] <= 0) res.fulfill(args.ctx, result);
return res;
}
@Expose(target = ExposeTarget.STATIC)
public static PromiseLib __allSettled(Arguments args) {
if (!(args.get(0) instanceof ArrayValue)) throw EngineException.ofType("Expected argument for any to be an array.");
var promises = args.convert(0, ArrayValue.class);
var n = new int[] { promises.size() };
var res = new PromiseLib();
var result = new ArrayValue();
for (var i = 0; i < promises.size(); i++) {
if (res.state != STATE_PENDING) break;
var index = i;
handle(args.ctx, promises.get(i), new Handle() {
@Override public void onFulfil(Object val) {
var desc = new ObjectValue();
desc.defineProperty(args.ctx, "status", "fulfilled");
desc.defineProperty(args.ctx, "value", val);
result.set(args.ctx, index, desc);
n[0]--;
if (n[0] <= 0) res.fulfill(args.ctx, res);
}
@Override public void onReject(EngineException err) {
var desc = new ObjectValue();
desc.defineProperty(args.ctx, "status", "reject");
desc.defineProperty(args.ctx, "value", err.value);
result.set(args.ctx, index, desc);
n[0]--;
if (n[0] <= 0) res.fulfill(args.ctx, res);
}
});
}
if (n[0] <= 0) res.fulfill(args.ctx, result);
return res;
}
@Expose
public static Object __then(Arguments args) {
var onFulfill = args.get(0) instanceof FunctionValue ? args.convert(0, FunctionValue.class) : null;
var onReject = args.get(1) instanceof FunctionValue ? args.convert(1, FunctionValue.class) : null;
var res = new PromiseLib();
handle(args.ctx, args.self, new Handle() {
@Override public void onFulfil(Object val) {
try { res.fulfill(args.ctx, onFulfill.call(args.ctx, null, val)); }
catch (EngineException e) { res.reject(args.ctx, e); }
}
@Override public void onReject(EngineException err) {
try { res.fulfill(args.ctx, onReject.call(args.ctx, null, err.value)); }
catch (EngineException e) { res.reject(args.ctx, e); }
}
}.defer(args.ctx));
return res;
}
@Expose
public static Object __catch(Arguments args) {
return __then(new Arguments(args.ctx, args.self, null, args.get(0)));
}
@Expose
public static Object __finally(Arguments args) {
var func = args.get(0) instanceof FunctionValue ? args.convert(0, FunctionValue.class) : null;
var res = new PromiseLib();
handle(args.ctx, args.self, new Handle() {
@Override public void onFulfil(Object val) {
try {
func.call(args.ctx);
res.fulfill(args.ctx, val);
}
catch (EngineException e) { res.reject(args.ctx, e); }
}
@Override public void onReject(EngineException err) {
try {
func.call(args.ctx);
res.reject(args.ctx, err);
}
catch (EngineException e) { res.reject(args.ctx, e); }
}
}.defer(args.ctx));
return res;
}
@ExposeConstructor
public static PromiseLib __constructor(Arguments args) {
var func = args.convert(0, FunctionValue.class);
var res = new PromiseLib();
try {
func.call(
args.ctx, null,
new NativeFunction(null, _args -> {
res.fulfill(_args.ctx, _args.get(0));
return null;
}),
new NativeFunction(null, _args -> {
res.reject(_args.ctx, new EngineException(_args.get(0)).setExtensions(_args.ctx));
return null;
})
);
}
catch (EngineException e) {
res.reject(args.ctx, e);
}
return res;
}
}