AtomicGameEngine/Source/AtomicJS/Javascript/JSAPI.cpp

//
// Copyright (c) 2014-2015, THUNDERBEAST GAMES LLC All rights reserved
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
//
// The above copyright notice and this permission notice shall be included in
// all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
// THE SOFTWARE.
//

#include <Atomic/Core/Context.h>
#include <Atomic/Resource/ResourceCache.h>
#include <Atomic/Script/ScriptVector.h>

#include "JSAPI.h"
#include "JSVM.h"

/*

  // script can new an instance
  // script can get an engine ptr back (which may be to a previously script new'd instance)
  // script should always get the same JS Object back which means a lookup table (strong ref)
  // we can look directly at the tval (exposed from duktape internals) to see if the reference count is 1

  // script owned
  // new'd script side, script holds a RefCounted reference

  // native owned

  // native script classes not derived from refcounted
  // if not inherited from RefCounted can script access?
  // if so, script side will always need to delete?

*/

namespace Atomic
{

    void js_class_get_prototype(duk_context* ctx, const char* package, const char *classname)
    {
        duk_get_global_string(ctx, package);
        duk_get_prop_string(ctx, -1, classname);
        duk_get_prop_string(ctx, -1, "prototype");
        duk_remove(ctx, -2); // remove class object
        duk_remove(ctx, -2); // remove Atomic object
    }

    void js_class_get_constructor(duk_context* ctx, const char* package, const char *classname)
    {
        duk_get_global_string(ctx, package);
        duk_get_prop_string(ctx, -1, classname);
        duk_remove(ctx, -2); // remove package
    }

    void js_constructor_basecall(duk_context* ctx, const char* package, const char* baseclass)
    {
        int top = duk_get_top(ctx);
        duk_get_global_string(ctx, package);
        duk_get_prop_string(ctx, -1, baseclass);
        assert(duk_is_function(ctx, -1));
        duk_push_this(ctx);
        duk_call_method(ctx, 0);
        duk_pop_n(ctx, 2);
        assert(top == duk_get_top(ctx));
    }

    void js_class_declare_internal(JSVM* vm, void* uniqueClassID, const char* package, const char* classname, duk_c_function constructor)
    {
        duk_context* ctx = vm->GetJSContext();

        // uniqueClassID must be non-null
        assert(uniqueClassID);

        // stash a lookup from the uniqueID to the package and class name

        duk_push_heap_stash(ctx);
        duk_push_pointer(ctx, uniqueClassID);

        duk_push_object(ctx);
        duk_push_string(ctx, package);
        duk_put_prop_index(ctx, -2, 0);
        duk_push_string(ctx, classname);
        duk_put_prop_index(ctx, -2, 1);

        // store class object into uniqueClassID key
        duk_put_prop(ctx, -3);

        // pop heap stash
        duk_pop(ctx);

        // store the constructor
        duk_get_global_string(ctx, package);
        duk_push_c_function(ctx, constructor, DUK_VARARGS);
        duk_put_prop_string(ctx, -2, classname);
        duk_pop(ctx);
    }

    void js_class_push_propertyobject(JSVM* vm, const char* package, const char* classname)
    {
        duk_context* ctx = vm->GetJSContext();
        String pname;
        pname.AppendWithFormat("__%s__Properties", classname);

        duk_get_global_string(ctx, package);
        duk_push_object(ctx);
        duk_dup(ctx, -1);
        duk_put_prop_string(ctx, -3, pname.CString());
        duk_remove(ctx, -2); // remove Atomic object
    }

    void js_setup_prototype(JSVM* vm, const char* package, const char* classname, const char* basePackage, const char* basename, bool hasProperties)
    {
        duk_context* ctx = vm->GetJSContext();

        String pname;
        pname.AppendWithFormat("__%s__Properties", classname);

        int top = duk_get_top(ctx);

        duk_get_global_string(ctx, package);
        duk_get_prop_string(ctx, -1, classname);
        assert(duk_is_c_function(ctx, -1));

        if (!strlen(basename))
        {
            // prototype
            duk_push_object(ctx);
            duk_dup(ctx, -2); // AObject constructor function
            duk_put_prop_string(ctx, -2, "constructor");
            duk_put_prop_string(ctx, -2, "prototype");

            duk_pop_n(ctx, 2);

            assert(top == duk_get_top(ctx));

            return;

        }

        // prototype
        duk_get_global_string(ctx, "Object");
        duk_get_prop_string(ctx, -1, "create");

        assert(duk_is_function(ctx, -1));

        duk_remove(ctx, -2); // remove Object

        duk_get_global_string(ctx, basePackage);
        duk_get_prop_string(ctx, -1, basename);
        assert(duk_is_function(ctx, -1));
        duk_get_prop_string(ctx, -1, "prototype");

        assert(duk_is_object(ctx, -1));

        duk_remove(ctx, -2); // remove basename

        int numargs = 1;
        if (hasProperties)
        {
            duk_get_global_string(ctx, package);
            duk_get_prop_string(ctx, -1, pname.CString());
            assert(duk_is_object(ctx, -1));
            duk_remove(ctx, -2);
            duk_remove(ctx, -3); // remove package
            numargs++;
        }
        else
            duk_remove(ctx, -2); // remove package

        duk_call(ctx, numargs);

        assert(duk_is_object(ctx, -1));

        duk_dup(ctx, -2);
        duk_put_prop_string(ctx, -2, "constructor");

        //duk_dup(ctx, -1);
        duk_put_prop_string(ctx, -2, "prototype");

        // pop the classname object
        duk_pop(ctx);

        // pop the Atomic Object
        duk_pop(ctx);

        assert(top == duk_get_top(ctx));
    }


    // When subscribing to native event, this method will be called
    // to provide the event meta data (type and callback)
    static int js_push_native_event_metadata(duk_context* ctx) {

        duk_push_current_function(ctx);

        duk_push_object(ctx);
        duk_get_prop_string(ctx, -2, "_eventType");
        duk_put_prop_string(ctx, -2, "_eventType");
        duk_dup(ctx, 0);
        duk_put_prop_string(ctx, -2, "_callback");

        return 1;
    }

    void js_define_native_event(duk_context* ctx, const String& eventType, const String &eventName)
    {
        // push c function which takes 1 argument, the callback
        duk_push_c_function(ctx, js_push_native_event_metadata, 1);

        // store the event type in the function object
        duk_push_string(ctx, eventType.CString());
        duk_put_prop_string(ctx, -2, "_eventType");

        // store to module object
        duk_put_prop_string(ctx, -2, eventName.CString());

    }

    void js_object_to_variantmap(duk_context* ctx, int objIdx, VariantMap &v)
    {
        v.Clear();

        duk_enum(ctx, objIdx, DUK_ENUM_OWN_PROPERTIES_ONLY);

        while (duk_next(ctx, -1 /*enum_index*/, 1 /*get_value*/)) {

            /* [ ... enum key ] */

            const char* key = duk_to_string(ctx, -2);

            if (duk_is_number(ctx, -1)) {

                v[key] = (float)duk_to_number(ctx, -1);

            }
            else if (duk_is_boolean(ctx, -1)) {

                v[key] = duk_to_boolean(ctx, -1) ? true : false;

            }
            else if (duk_is_string(ctx, -1)) {

                v[key] = duk_to_string(ctx, -1);

            }
            else if (duk_get_heapptr(ctx, -1)) {

                v[key] = js_to_class_instance<Object>(ctx, -1, 0);

            }

            duk_pop_2(ctx);  /* pop_key & value*/
        }

        duk_pop(ctx);  /* pop enum object */

    }

    duk_bool_t js_check_is_buffer_and_get_data(duk_context* ctx, duk_idx_t idx, void** data, duk_size_t* size)
    {
        void* temp;
        if (duk_is_buffer(ctx, idx))
        {
            temp = duk_get_buffer_data(ctx, idx, size);
            if (data)
            {
                *data = temp;
            }
            return true;
        }
        if (!(duk_is_object(ctx, idx) &&
            duk_has_prop_string(ctx, idx, "length") &&
            duk_has_prop_string(ctx, idx, "byteLength") &&
            duk_has_prop_string(ctx, idx, "byteOffset") &&
            duk_has_prop_string(ctx, idx, "BYTES_PER_ELEMENT")))
        {
            if (data)
            {
                *data = nullptr;
            }
            if (size)
            {
                *size = 0;
            }
            return false;
        }
        temp = duk_require_buffer_data(ctx, idx, size);
        if (data)
        {
            *data = temp;
        }
        return true;
    }

    void js_get_default_variant(VariantType variantType, Variant& value)
    {
        value = Variant::EMPTY;
        
        switch (variantType)
        {

        case VAR_NONE:
            break;

        case VAR_INT:
            value = 0;
            break;

        case VAR_BOOL:
            value = false;
            break;

        case VAR_FLOAT:
            value = 0.0f;
            break;

        case VAR_VECTOR2:
            value = Vector2::ZERO;
            break;

        case VAR_VECTOR3:
            value = Vector3::ZERO;
            break;

        case VAR_VECTOR4:
            value = Vector4::ZERO;
            break;

        case VAR_QUATERNION:
            value = Quaternion::IDENTITY;
            break;

        case VAR_COLOR:
            value = Color::WHITE;
            break;

        case VAR_STRING:
            value = "";
            break;

        case VAR_INTRECT:
            value = IntRect::ZERO;
            break;

        case VAR_INTVECTOR2:
            value = IntVector2::ZERO;
            break;

        case VAR_DOUBLE:
            // set float here too, so standard edits work
            value = 0.0f;
            break;

        case VAR_RESOURCEREF:            
            value = ResourceRef();
            break;

        default:
            break;
        }
        
    }

    void js_to_variant(duk_context* ctx, int variantIdx, Variant &v, VariantType variantType)
    {
        v.Clear();

        // convert to abs index
        if (variantIdx < 0)
            variantIdx = duk_get_top(ctx) + variantIdx;

        if (duk_is_boolean(ctx, variantIdx))
        {
            v = duk_to_boolean(ctx, variantIdx) ? true : false;
            return;
        }

        if (duk_is_string(ctx, variantIdx))
        {
            v = duk_to_string(ctx, variantIdx);
            return;
        }

        if (duk_is_number(ctx, variantIdx))
        {
            v = (float)duk_to_number(ctx, variantIdx);
            return;
        }

        if (duk_is_pointer(ctx, variantIdx))
        {
            v = (RefCounted*)duk_get_pointer(ctx, variantIdx);
            return;
        }

        if (duk_is_array(ctx, variantIdx))
        {
            if (duk_get_length(ctx, variantIdx) == 2)
            {
                Vector2 v2;
                duk_get_prop_index(ctx, variantIdx, 0);
                v2.x_ = duk_to_number(ctx, -1);
                duk_get_prop_index(ctx, variantIdx, 1);
                v2.y_ = duk_to_number(ctx, -1);
                duk_pop_n(ctx, 2);
                v = v2;
                return;
            }
            else if (duk_get_length(ctx, variantIdx) == 3)
            {
                Vector3 v3;
                duk_get_prop_index(ctx, variantIdx, 0);
                v3.x_ = duk_to_number(ctx, -1);
                duk_get_prop_index(ctx, variantIdx, 1);
                v3.y_ = duk_to_number(ctx, -1);
                duk_get_prop_index(ctx, variantIdx, 2);
                v3.z_ = duk_to_number(ctx, -1);
                duk_pop_n(ctx, 3);
                v = v3;
                return;
            }
            else if (duk_get_length(ctx, variantIdx) == 4)
            {
                Vector4 v4;
                duk_get_prop_index(ctx, variantIdx, 0);
                v4.x_ = duk_to_number(ctx, -1);
                duk_get_prop_index(ctx, variantIdx, 1);
                v4.y_ = duk_to_number(ctx, -1);
                duk_get_prop_index(ctx, variantIdx, 2);
                v4.z_ = duk_to_number(ctx, -1);
                duk_get_prop_index(ctx, variantIdx, 3);
                v4.w_ = duk_to_number(ctx, -1);
                duk_pop_n(ctx, 4);
                v = v4;
                return;
            }


            return;
        }

        {
            void* bufferData;
            duk_size_t bufferSize;
            if (js_check_is_buffer_and_get_data(ctx, variantIdx, &bufferData, &bufferSize))
            {
                // copy the buffer into the variant
                v.SetBuffer(bufferData, (unsigned)bufferSize);
                return;
            }
        }

        // object check after array and buffer object check
        if (duk_is_object(ctx, variantIdx))
        {
            if (variantType == VAR_RESOURCEREFLIST)
            {
                ResourceRefList refList;

                duk_get_prop_string(ctx, variantIdx, "typeName");
                refList.type_ = duk_to_string(ctx, -1);

                duk_get_prop_string(ctx, variantIdx, "resources");
                int length = duk_get_length(ctx, -1);

                for (int i = 0; i < length; i++) {

                    duk_get_prop_index(ctx, -1, i);

                    Resource* resource = NULL;

                    if (duk_is_object(ctx, -1))
                    {
                        resource = js_to_class_instance<Resource>(ctx, -1, 0);

                    }

                    if (resource) {
                        refList.names_.Push(resource->GetName());
                    }
                    else
                        refList.names_.Push(String::EMPTY);

                    duk_pop(ctx);
                }

                duk_pop_n(ctx, 2);

                v = refList;
            }
            else
            {
                RefCounted* o = js_to_class_instance<RefCounted>(ctx, variantIdx, 0);
                if (o)
                    v = o;
            }

            return;
        }


    }

    // variant map Proxy getter, so we can convert access to string based
    // member lookup, to string hash on the fly

    static int variantmap_property_get(duk_context* ctx)
    {
        // targ, key, recv

        if (duk_is_string(ctx, 1))
        {
            StringHash key = duk_to_string(ctx, 1);
            duk_get_prop_index(ctx, 0, (unsigned)key.Value());
            return 1;
        }

        duk_push_undefined(ctx);
        return 1;

    }

    // removes all keys from the variant map proxy target, REGARDLESS of key given for delete
    // see (lengthy) note in JSEventDispatcher::EndSendEvent
    static int variantmap_property_deleteproperty(duk_context* ctx)
    {
        // deleteProperty: function (targ, key)

        duk_enum(ctx, 0, DUK_ENUM_OWN_PROPERTIES_ONLY);

        while (duk_next(ctx, -1, 0)) {
            duk_del_prop(ctx, 0);
        }

        duk_push_boolean(ctx, 1);
        return 1;

    }


    void js_push_variantmap(duk_context* ctx, const VariantMap &vmap)
    {

        // setup proxy so we can map string
        duk_get_global_string(ctx, "Proxy");

        duk_push_object(ctx);

        VariantMap::ConstIterator itr = vmap.Begin();

        while (itr != vmap.End()) {

            js_push_variant(ctx, itr->second_);


            if (duk_is_undefined(ctx, -1)) {

                duk_pop(ctx);
            }
            else
            {
                duk_put_prop_index(ctx, -2, (unsigned)itr->first_.Value());
            }

            itr++;

        }

        // setup property handler
        duk_push_object(ctx);
        duk_push_c_function(ctx, variantmap_property_get, 3);
        duk_put_prop_string(ctx, -2, "get");
        duk_push_c_function(ctx, variantmap_property_deleteproperty, 2);
        duk_put_prop_string(ctx, -2, "deleteProperty");

        duk_new(ctx, 2);


    }

    void js_push_variant(duk_context *ctx, const Variant& v, int arrayIndex)
    {
        switch (v.GetType())
        {
        case VAR_NONE:
            duk_push_undefined(ctx);
            break;

        case VAR_VOIDPTR:
            duk_push_null(ctx);
            break;

        case VAR_PTR:
        {
            RefCounted* ref = v.GetPtr();

            // if we're null or don't have any refs, return null
            if (!ref || !ref->Refs())
            {
                duk_push_null(ctx);
                break;
            }

            // check that class is supported
            duk_push_heap_stash(ctx);
            duk_push_pointer(ctx, (void*)ref->GetClassID());
            duk_get_prop(ctx, -2);

            if (!duk_is_object(ctx, -1))
            {
                duk_pop_2(ctx);
                duk_push_undefined(ctx);
            }
            else
            {
                duk_pop_2(ctx);
                js_push_class_object_instance(ctx, ref);
            }

        }   break;

        case VAR_RESOURCEREF:
        {
            const ResourceRef& resourceRef(v.GetResourceRef());
            ResourceCache* cache = JSVM::GetJSVM(ctx)->GetContext()->GetSubsystem<ResourceCache>();
            Resource* resource = cache->GetResource(resourceRef.type_, resourceRef.name_);
            js_push_class_object_instance(ctx, resource);
        }   break;

        case VAR_RESOURCEREFLIST:
        {

            const ResourceRefList& resourceRefList(v.GetResourceRefList());
            const Context* context = JSVM::GetJSVM(ctx)->GetContext();

            duk_push_object(ctx);
            duk_push_string(ctx, context->GetTypeName(resourceRefList.type_).CString());
            duk_put_prop_string(ctx, -2, "typeName");

            duk_push_array(ctx);

            ResourceCache* cache = context->GetSubsystem<ResourceCache>();

            for (unsigned i = 0; i < resourceRefList.names_.Size(); i++) {

                Resource* resource = cache->GetResource(resourceRefList.type_, resourceRefList.names_[i]);
                js_push_class_object_instance(ctx, resource);
                duk_put_prop_index(ctx, -2, i);
            }

            duk_put_prop_string(ctx, -2, "resources");

        } break;

        case VAR_BOOL:
            duk_push_boolean(ctx, v.GetBool() ? 1 : 0);
            break;

        case VAR_INT:
            duk_push_number(ctx, v.GetInt());
            break;

        case VAR_FLOAT:
            duk_push_number(ctx, v.GetFloat());
            break;

        case VAR_DOUBLE:
            duk_push_number(ctx, v.GetFloat());
            break;

        case VAR_STRING:
        {
            const String& string(v.GetString());
            duk_push_lstring(ctx, string.CString(), string.Length());
        }   break;

        case VAR_BUFFER:
        {
            const PODVector<unsigned char>& buffer(v.GetBuffer()); // The braces are to scope this reference.
            duk_push_fixed_buffer(ctx, buffer.Size());
            duk_push_buffer_object(ctx, -1, 0, buffer.Size(), DUK_BUFOBJ_UINT8ARRAY);
            duk_replace(ctx, -2);
            unsigned char* data = (unsigned char*)duk_require_buffer_data(ctx, -1, (duk_size_t*)nullptr);
            memcpy(data, buffer.Buffer(), buffer.Size());
        }   break;

        case VAR_VECTOR2:
        {
            const Vector2& vector2(v.GetVector2());
            duk_push_array(ctx);
            duk_push_number(ctx, vector2.x_);
            duk_put_prop_index(ctx, -2, 0);
            duk_push_number(ctx, vector2.y_);
            duk_put_prop_index(ctx, -2, 1);
        }   break;

        case VAR_INTVECTOR2:
        {
            const IntVector2& intVector2(v.GetIntVector2());
            duk_push_array(ctx);
            duk_push_number(ctx, intVector2.x_);
            duk_put_prop_index(ctx, -2, 0);
            duk_push_number(ctx, intVector2.y_);
            duk_put_prop_index(ctx, -2, 1);
        }   break;

        case VAR_VECTOR3:
        {
            const Vector3& vector3(v.GetVector3());
            duk_push_array(ctx);
            duk_push_number(ctx, vector3.x_);
            duk_put_prop_index(ctx, -2, 0);
            duk_push_number(ctx, vector3.y_);
            duk_put_prop_index(ctx, -2, 1);
            duk_push_number(ctx, vector3.z_);
            duk_put_prop_index(ctx, -2, 2);
        }   break;

        case VAR_QUATERNION:
        {
            const Vector3& vector3(v.GetQuaternion().EulerAngles());
            duk_push_array(ctx);
            duk_push_number(ctx, vector3.x_);
            duk_put_prop_index(ctx, -2, 0);
            duk_push_number(ctx, vector3.y_);
            duk_put_prop_index(ctx, -2, 1);
            duk_push_number(ctx, vector3.z_);
            duk_put_prop_index(ctx, -2, 2);
        }   break;

        case VAR_COLOR:
        {
            const Color& color(v.GetColor());
            duk_push_array(ctx);
            duk_push_number(ctx, color.r_);
            duk_put_prop_index(ctx, -2, 0);
            duk_push_number(ctx, color.g_);
            duk_put_prop_index(ctx, -2, 1);
            duk_push_number(ctx, color.b_);
            duk_put_prop_index(ctx, -2, 2);
            duk_push_number(ctx, color.a_);
            duk_put_prop_index(ctx, -2, 3);
        }   break;

        case VAR_VECTOR4:
        {
            const Vector4& vector4(v.GetVector4());
            duk_push_array(ctx);
            duk_push_number(ctx, vector4.x_);
            duk_put_prop_index(ctx, -2, 0);
            duk_push_number(ctx, vector4.y_);
            duk_put_prop_index(ctx, -2, 1);
            duk_push_number(ctx, vector4.z_);
            duk_put_prop_index(ctx, -2, 2);
            duk_push_number(ctx, vector4.w_);
            duk_put_prop_index(ctx, -2, 3);
        }   break;

        case VAR_VARIANTVECTOR:
        {
            const VariantVector& vector(v.GetVariantVector());

            // if we don't specify an array index, wrap and push the vector (EXPENSIVE!)
            if (arrayIndex == -1)
            {
                SharedPtr<ScriptVector> scriptVector(new ScriptVector());
                scriptVector->AdaptFromVector(vector);
                js_push_class_object_instance(ctx, scriptVector);
            }
            else
            {
                if (arrayIndex < 0 || arrayIndex >= vector.Size())
                {
                    duk_push_undefined(ctx);
                }
                else
                {
                    // recursively push the variant
                    js_push_variant(ctx, vector[arrayIndex]);
                }
            }

        }   break;

        default:
            duk_push_undefined(ctx);
            break;
        }


    }


}