#include "Gameplay.hpp"
#include <algorithm>
#include <cmath>
#include <map>

namespace faset::gameplay {
void registerGameplay(runtime::Runtime& engine) {
    runtime::Behavior character;
    character.fixedUpdate=[](runtime::Runtime& world,runtime::EntityHandle self,double) {
        const auto fields=world.fields(self,"gameplay.character");
        auto velocity=world.velocity(self);const auto input=world.input();
        velocity[0]=input.horizontal*fields.value("speed",4.0f);
        // A minimal demo controller: jump only near zero vertical velocity.
        // A production grounded controller needs contact normals / a ground query.
        if(input.jumpPressed&&std::abs(velocity[1])<0.1f)velocity[1]=fields.value("jump_speed",5.0f);
        world.setVelocity(self,velocity);
    };
    engine.registerBehavior("gameplay.character",std::move(character));

    runtime::Behavior door;
    auto open=std::make_shared<std::map<std::pair<std::uint64_t,std::uint32_t>,bool>>();
    door.onStart=[open](runtime::Runtime&,runtime::EntityHandle self,double){(*open)[{self.session,self.slot}]=false;};
    door.onDestroy=[open](runtime::Runtime&,runtime::EntityHandle self,double){open->erase({self.session,self.slot});};
    door.fixedUpdate=[open](runtime::Runtime& world,runtime::EntityHandle self,double dt) {
        const auto fields=world.fields(self,"gameplay.door");
        auto pose=world.transform(self);
        auto& opened=(*open)[{self.session,self.slot}];
        if(world.input().interactPressed)opened=!opened;
        const float target=opened?fields.value("open_angle",1.5707963f):fields.value("closed_angle",0.0f);
        const float distance=target-pose.rotation[1];
        const float amount=std::max(0.0f,fields.value("speed",1.5f))*static_cast<float>(dt);
        pose.rotation[1]+=std::clamp(distance,-amount,amount);
        world.setTransform(self,pose);
    };
    engine.registerBehavior("gameplay.door",std::move(door));
}

nlohmann::json schema() {
    // Explicit declarations shared by Player and SchemaExporter. This function
    // constructs descriptions only: no Runtime, physics world or lifecycle.
    return nlohmann::json::array({
        {{"id","gameplay.character"},{"version",1},{"name","Character"},{"fields",{
            {"speed",{{"id","speed"},{"type","number"},{"default",4.0},{"min",0.0}}},
            {"jump_speed",{{"id","jump_speed"},{"type","number"},{"default",5.0},{"min",0.0}}}}}},
        {{"id","gameplay.door"},{"version",1},{"name","Door"},{"fields",{
            {"open_angle",{{"id","open_angle"},{"type","number"},{"default",1.5707963},{"units","rad"}}},
            {"closed_angle",{{"id","closed_angle"},{"type","number"},{"default",0.0},{"units","rad"}}},
            {"speed",{{"id","speed"},{"type","number"},{"default",1.5},{"min",0.0},{"units","rad/s"}}}}}}
    });
}
}