#pragma once
#include "YYCCInternal.hpp"
#if YYCC_OS == YYCC_OS_WINDOWS

#include <string>
#include <vector>
#include <initializer_list>
#include <memory>

#include "WinImportPrefix.hpp"
#include <Windows.h>
#include <shlobj_core.h>
#include <commdlg.h>
#include "WinImportSuffix.hpp"

namespace YYCC::DialogHelper {

	/**
	 * @brief The class represent the file types region in file dialog
	 * @details THis class is specific for Windows use, not user oriented.
	*/
	class WinFileFilters {
		friend class FileFilters;
	public:
		WinFileFilters() : m_WinFilters(), m_WinDataStruct(nullptr) {}

		UINT GetFilterCount() const {
			return static_cast<UINT>(m_WinFilters.size());
		}
		const COMDLG_FILTERSPEC* GetFilterSpecs() const {
			return m_WinDataStruct.get();
		}

	protected:
		using WinFilterModes = std::wstring;
		using WinFilterName = std::wstring;
		using WinFilterPair = std::pair<WinFilterName, WinFilterModes>;

		std::vector<WinFilterPair> m_WinFilters;
		std::unique_ptr<COMDLG_FILTERSPEC[]> m_WinDataStruct;
	};

	/**
	 * @brief The class represent the file types region in file dialog.
	 * @details THis class is user oriented. User can use function manipulate file types
	 * and final fialog function will produce Windows-understood data struct from this.
	*/
	class FileFilters {
	public:
		FileFilters() : m_Filters(){}

		/**
		 * @brief Add a filter pair in file types list.
		 * @param filter_name[in] The friendly name of the filter.
		 * @param il[in] A C++ initialize list.
		 * Every entries must be `const char*` represent a single filter pattern.
		 * The list at least should have one valid pattern.
		 * This function will not validate these filter patterns, so please write them carefully.
		 * @return True if added success, otherwise false.
		 * @remarks This function allow you register multiple filter patterns for single friendly name.
		 * For example: `Add("Microsoft Word (*.doc; *.docx)", {"*.doc", "*.docx"})`
		*/
		bool Add(const char* filter_name, std::initializer_list<const char*> il);
		/**
		 * @brief Clear filter pairs for following re-use.
		*/
		void Clear() { m_Filters.clear(); }
		/**
		 * @brief Get the count of added filter pairs.
		 * @return The count of already added filter pairs.
		*/
		size_t Count() const { return m_Filters.size(); }

		/**
		 * @brief Generate Windows dialog system used data struct.
		 * @param win_result[out] The class holding the generated filter data struct.
		 * @return True if generation is success, otherwise false.
		*/
		bool Generate(WinFileFilters& win_result) const;

	protected:
		using FilterModes = std::vector<std::string>;
		using FilterName = std::string;
		using FilterPair = std::pair<FilterName, FilterModes>;

		std::vector<FilterPair> m_Filters;
	};

	class FileDialog {
	public:
		FileDialog() :
			m_Owner(NULL), m_Title(),
			m_FileTypes(),
			m_DefaultFileTypeIndex(0u),
			m_InitFileName(), m_InitDirectory() {}

		void SetOwner(HWND owner) { m_Owner = owner; }
		HWND GetOwner() const { return m_Owner; }

		void SetTitle(const char* title) {
			if (title == nullptr) m_Title.clear();
			else m_Title = title;
		}
		const char* GetTitle() const {
			if (m_Title.empty()) return nullptr;
			else return m_Title.c_str();
		}

		FileFilters& GetFileTypes() {
			return m_FileTypes;
		}
		const FileFilters& GetFileTypes() const {
			return m_FileTypes;
		}

		void SetDefaultFileTypeIndex(UINT idx) { m_DefaultFileTypeIndex = idx; }
		UINT GetDefaultFileTypeIndex() const { return m_DefaultFileTypeIndex; }
		
		void SetInitFileName(const char* init_filename) {
			if (init_filename == nullptr) m_InitFileName.clear();
			else m_InitFileName = init_filename;
		}
		const char* GetInitFileName() const {
			if (m_InitFileName.empty()) return nullptr;
			else return m_InitFileName.c_str();
		}
		
		void SetInitDirectory(const char* init_dir) {
			if (init_dir == nullptr) m_InitDirectory.clear();
			else m_InitDirectory = init_dir;
		}
		const char* GetInitDirectory() const {
			if (m_InitDirectory.empty()) return nullptr;
			else return m_InitDirectory.c_str();
		}

	private:
		HWND m_Owner;
		std::string m_Title;
		FileFilters m_FileTypes;
		UINT m_DefaultFileTypeIndex;
		std::string m_InitFileName;
		std::string m_InitDirectory;
	};

	bool OpenFileDialog(const FileDialog& params, std::string& ret);
	bool OpenMultipleFileDialog(const FileDialog& params, std::vector<std::string>& ret);
	bool SaveFileDialog(const FileDialog& params, std::string& ret);

	bool OpenFolderDialog(const FileDialog& params, std::string& ret);

}

#endif