//
//	ComponentGrid.h
//
//	Provides basic layout of components in an X*Y grid.
//

#pragma once
#ifndef ES_CORE_COMPONENTS_COMPONENT_GRID_H
#define ES_CORE_COMPONENTS_COMPONENT_GRID_H

#include "math/Vector2i.h"
#include "renderers/Renderer.h"
#include "GuiComponent.h"

namespace GridFlags
{
	enum UpdateType {
		UPDATE_ALWAYS,
		UPDATE_WHEN_SELECTED,
		UPDATE_NEVER
	};

	enum Border : unsigned int {
		BORDER_NONE = 0,

		BORDER_TOP = 1,
		BORDER_BOTTOM = 2,
		BORDER_LEFT = 4,
		BORDER_RIGHT = 8
	};
};

// Used to arrange a bunch of components in a spreadsheet-esque grid.
class ComponentGrid : public GuiComponent
{
public:
	ComponentGrid(Window* window, const Vector2i& gridDimensions);
	virtual ~ComponentGrid();

	bool removeEntry(const std::shared_ptr<GuiComponent>& comp);

	void setEntry(
			const std::shared_ptr<GuiComponent>& comp,
			const Vector2i& pos,
			bool canFocus,
			bool resize = true,
			const Vector2i& size = Vector2i(1, 1),
			unsigned int border = GridFlags::BORDER_NONE,
			GridFlags::UpdateType updateType = GridFlags::UPDATE_ALWAYS);

	void textInput(const char* text) override;
	bool input(InputConfig* config, Input input) override;
	void update(int deltaTime) override;
	void render(const Transform4x4f& parentTrans) override;
	void onSizeChanged() override;

	void resetCursor();
	bool cursorValid();

	float getColWidth(int col);
	float getRowHeight(int row);

	// If update is false, will not call an onSizeChanged() which triggers
	// a (potentially costly) repositioning + resizing of every element.
	void setColWidthPerc(int col, float width, bool update = true);
	// Dito.
	void setRowHeightPerc(int row, float height, bool update = true);

	bool moveCursor(Vector2i dir);
	void setCursorTo(const std::shared_ptr<GuiComponent>& comp);

	inline std::shared_ptr<GuiComponent> getSelectedComponent()
	{
		const GridEntry* e = getCellAt(mCursor);
		if(e)
			return e->component;
		else
			return nullptr;
	}

	void onFocusLost() override;
	void onFocusGained() override;

	virtual std::vector<HelpPrompt> getHelpPrompts() override;

private:
	class GridEntry
	{
	public:
		Vector2i pos;
		Vector2i dim;
		std::shared_ptr<GuiComponent> component;
		bool canFocus;
		bool resize;
		GridFlags::UpdateType updateType;
		unsigned int border;

		GridEntry(const Vector2i& p = Vector2i::Zero(), const Vector2i& d = Vector2i::Zero(),
			const std::shared_ptr<GuiComponent>& cmp = nullptr, bool f = false, bool r = true,
			GridFlags::UpdateType u = GridFlags::UPDATE_ALWAYS, unsigned int b =
					GridFlags::BORDER_NONE) :
			pos(p), dim(d), component(cmp), canFocus(f), resize(r), updateType(u), border(b)
		{};

		operator bool() const
		{
			return component != NULL;
		}
	};

	float* mRowHeights;
	float* mColWidths;

	std::vector<Renderer::Vertex> mLines;

	// Update position & size.
	void updateCellComponent(const GridEntry& cell);
	void updateSeparators();

	const GridEntry* getCellAt(int x, int y) const;
	inline const GridEntry* getCellAt(const Vector2i& pos) const
			{ return getCellAt(pos.x(), pos.y()); }

	Vector2i mGridSize;

	std::vector<GridEntry> mCells;

	void onCursorMoved(Vector2i from, Vector2i to);
	Vector2i mCursor;
};

#endif // ES_CORE_COMPONENTS_COMPONENT_GRID_H