package org.openautonomousconnection.luascript.tables;

import org.luaj.vm2.LuaTable;
import org.luaj.vm2.LuaValue;
import org.luaj.vm2.lib.OneArgFunction;
import org.luaj.vm2.lib.TwoArgFunction;
import org.luaj.vm2.lib.VarArgFunction;
import org.luaj.vm2.Varargs;
import org.openautonomousconnection.luascript.events.JavaToLua;
import org.openautonomousconnection.luascript.hosts.GeometryHost;
import org.openautonomousconnection.luascript.hosts.HostServices;
import org.openautonomousconnection.luascript.utils.ScriptTable;

import java.util.Map;

/**
 * Lua table: geometry
 *
 * <p>Functions:</p>
 * <ul>
 *   <li>geometry.rect(id) -> map</li>
 *   <li>geometry.viewport() -> map</li>
 *   <li>geometry.scrollTo(x,y)</li>
 *   <li>geometry.scrollIntoView(id, align?)</li>
 * </ul>
 */
public final class GeometryTable extends ScriptTable {

    public GeometryTable() {
        super("geometry");
    }

    @Override
    protected void define(HostServices services) {
        GeometryHost host = services.geometry().orElseThrow(() -> new IllegalStateException("GeometryHost not provided"));

        table().set("rect", new OneArgFunction() {
            @Override
            public LuaValue call(LuaValue id) {
                Map<String, Object> m = host.getBoundingClientRect(id.checkjstring());
                return JavaToLua.coerce(m);
            }
        });

        table().set("viewport", new org.luaj.vm2.lib.ZeroArgFunction() {
            @Override
            public LuaValue call() {
                return JavaToLua.coerce(host.getViewport());
            }
        });

        table().set("scrollTo", new VarArgFunction() {
            @Override
            public Varargs invoke(Varargs args) {
                host.scrollTo(args.arg(1).checkdouble(), args.arg(2).checkdouble());
                return LuaValue.NIL;
            }
        });

        table().set("scrollIntoView", new VarArgFunction() {
            @Override
            public Varargs invoke(Varargs args) {
                String id = args.arg(1).checkjstring();
                String align = args.narg() >= 2 && !args.arg(2).isnil() ? args.arg(2).tojstring() : null;
                host.scrollIntoView(id, align);
                return LuaValue.NIL;
            }
        });
    }
}