#ifndef VOXEL_GENERATOR_GRAPH_H
#define VOXEL_GENERATOR_GRAPH_H

#include "../voxel_generator.h"
#include "program_graph.h"
#include "voxel_graph_runtime.h"

class VoxelGeneratorGraph : public VoxelGenerator {
	GDCLASS(VoxelGeneratorGraph, VoxelGenerator)
public:
	static const char *SIGNAL_NODE_NAME_CHANGED;

	enum NodeTypeID {
		NODE_CONSTANT,
		NODE_INPUT_X,
		NODE_INPUT_Y,
		NODE_INPUT_Z,
		NODE_OUTPUT_SDF,
		NODE_ADD,
		NODE_SUBTRACT,
		NODE_MULTIPLY,
		NODE_DIVIDE,
		NODE_SIN,
		NODE_FLOOR,
		NODE_ABS,
		NODE_SQRT,
		NODE_FRACT,
		NODE_STEPIFY,
		NODE_WRAP,
		NODE_MIN,
		NODE_MAX,
		NODE_DISTANCE_2D,
		NODE_DISTANCE_3D,
		NODE_CLAMP,
		NODE_MIX,
		NODE_REMAP,
		NODE_SMOOTHSTEP,
		NODE_CURVE,
		NODE_SELECT,
		NODE_NOISE_2D,
		NODE_NOISE_3D,
		NODE_IMAGE_2D,
		NODE_SDF_PLANE,
		NODE_SDF_BOX,
		NODE_SDF_SPHERE,
		NODE_SDF_TORUS,
		NODE_SDF_PREVIEW, // For debugging
		NODE_SDF_SPHERE_HEIGHTMAP,
		NODE_NORMALIZE_3D,
		NODE_FAST_NOISE_2D,
		NODE_FAST_NOISE_3D,
		NODE_FAST_NOISE_GRADIENT_2D,
		NODE_FAST_NOISE_GRADIENT_3D,
		NODE_TYPE_COUNT
	};

	VoxelGeneratorGraph();
	~VoxelGeneratorGraph();

	void clear();

	// Graph edition API
	// Important: functions editing the graph are NOT thread-safe.
	// They are expected to be used by the main thread (editor or game logic).

	uint32_t create_node(NodeTypeID type_id, Vector2 position, uint32_t id = ProgramGraph::NULL_ID);
	void remove_node(uint32_t node_id);

	bool can_connect(
			uint32_t src_node_id, uint32_t src_port_index, uint32_t dst_node_id, uint32_t dst_port_index) const;
	void add_connection(uint32_t src_node_id, uint32_t src_port_index, uint32_t dst_node_id, uint32_t dst_port_index);
	void remove_connection(
			uint32_t src_node_id, uint32_t src_port_index, uint32_t dst_node_id, uint32_t dst_port_index);
	void get_connections(std::vector<ProgramGraph::Connection> &connections) const;
	bool try_get_connection_to(ProgramGraph::PortLocation dst, ProgramGraph::PortLocation &out_src) const;

	bool has_node(uint32_t node_id) const;

	void set_node_name(uint32_t node_id, StringName name);
	StringName get_node_name(uint32_t node_id) const;
	uint32_t find_node_by_name(StringName name) const;

	Variant get_node_param(uint32_t node_id, uint32_t param_index) const;
	void set_node_param(uint32_t node_id, uint32_t param_index, Variant value);

	Variant get_node_default_input(uint32_t node_id, uint32_t input_index) const;
	void set_node_default_input(uint32_t node_id, uint32_t input_index, Variant value);

	Vector2 get_node_gui_position(uint32_t node_id) const;
	void set_node_gui_position(uint32_t node_id, Vector2 pos);

	NodeTypeID get_node_type_id(uint32_t node_id) const;
	PoolIntArray get_node_ids() const;
	uint32_t generate_node_id() { return _graph.generate_node_id(); }

	// VoxelGenerator implementation

	int get_used_channels_mask() const override;

	void generate_block(VoxelBlockRequest &input) override;
	float generate_single(const Vector3i &position);

	Ref<Resource> duplicate(bool p_subresources) const override;

	// Utility

	void bake_sphere_bumpmap(Ref<Image> im, float ref_radius, float min_height, float max_height);
	void bake_sphere_normalmap(Ref<Image> im, float ref_radius, float strength);

	// Internal

	VoxelGraphRuntime::CompilationResult compile();
	bool is_good() const;

	void generate_set(ArraySlice<float> in_x, ArraySlice<float> in_y, ArraySlice<float> in_z,
			ArraySlice<float> out_sdf);

	// Returns state from the last generator used in the current thread
	static const VoxelGraphRuntime::State &get_last_state_from_current_thread();

	uint32_t get_output_port_address(ProgramGraph::PortLocation port) const;

	// Debug

	float debug_measure_microseconds_per_voxel(bool singular);
	void debug_load_waves_preset();

private:
	Interval analyze_range(Vector3i min_pos, Vector3i max_pos);

	Dictionary get_graph_as_variant_data() const;
	void load_graph_from_variant_data(Dictionary data);

	int _b_get_node_type_count() const;
	Dictionary _b_get_node_type_info(int type_id) const;
	PoolIntArray _b_get_node_ids() const;
	Array _b_get_connections() const;
	// TODO Only exists because the UndoRedo API is confusing `null` with `absence of argument`...
	// See https://github.com/godotengine/godot/issues/36895
	void _b_set_node_param_null(int node_id, int param_index);
	float _b_generate_single(Vector3 pos);
	Dictionary _b_compile();

	void _on_subresource_changed();
	void connect_to_subresource_changes();

	static void _bind_methods();

	ProgramGraph _graph;

	// Only compiling and generation methods are thread-safe.

	VoxelGraphRuntime *_runtime = nullptr;
	RWLock *_runtime_lock = nullptr;

	struct Cache {
		std::vector<float> x_cache;
		std::vector<float> y_cache;
		std::vector<float> z_cache;
		std::vector<float> slice_cache;
		VoxelGraphRuntime::State state;
	};

	static thread_local Cache _cache;
};

VARIANT_ENUM_CAST(VoxelGeneratorGraph::NodeTypeID)

#endif // VOXEL_GENERATOR_GRAPH_H