#pragma once

#include "tl/detail/prologue.h"
#include <tl/span.h>
#include <tl/vector.h>
#include <tl/fixed_vector.h>
#include "tl/string.h"
#include "tl/detail/path_system_utils.h"
#include "tl/toolchain.h"

//////////////////////////////////////////////////////////////////////////

#define TL_DECLARE_STRING_LITERAL(struct_name, cstr_value)\
struct struct_name\
{\
	static const char* value() noexcept\
	{\
		return cstr_value;\
	}\
};

#define TL_DECLARE_STRING_VECTOR(struct_name, ...)\
struct struct_name\
{\
	static const tl::vector<const char*>& vector() noexcept\
	{\
		static tl::vector<const char*> s_vector {__VA_ARGS__};\
		return s_vector;\
	}\
};

#define TL_DECLARE_TLSTRING_VECTOR(struct_name, ...)\
struct struct_name\
{\
	static const tl::vector<tl::string>& vector() noexcept\
	{\
		static tl::vector<tl::string> s_vector {__VA_ARGS__};\
		return s_vector;\
	}\
};

//////////////////////////////////////////////////////////////////////////

namespace tl
{
namespace path_system
{
TL_DECLARE_STRING_LITERAL(back_t, "..");
TL_DECLARE_STRING_LITERAL(current_t, ".");
}
}

//////////////////////////////////////////////////////////////////////////

namespace tl
{
	
//////////////////////////////////////////////////////////////////////////

template <typename... Systems>
struct path_systems
{
	template<typename T>
	static T format_abs(int type_id, tl::span<const string> members) noexcept;
	static void parse_abs(tl::vector<string>& o_elements, int type_id, const char* path, size_t size) noexcept;
	static void parse_relative(tl::vector<string>& o_elements, const char* path, size_t size) noexcept;
	static int deduce_system_type(const char* path, size_t size) noexcept;
	static bool validate_abs_path(int type_id, tl::span<const string> members) noexcept;
	static const tl::vector<tl::vector<const char*> >& get_all_parse_separators() noexcept;

	template <typename TypeToCheck>
	static bool is(int type_id) noexcept;
};

//////////////////////////////////////////////////////////////////////////

template<typename custom_implementation, typename parse_separators, typename format_separator>
struct custom_path_system : public custom_implementation, public detail::path_system::base_path_system<parse_separators, format_separator> 
{
};

//////////////////////////////////////////////////////////////////////////

template<typename root_tag, typename parse_separators, typename format_separator>
struct simple_path_system : public detail::path_system::base_path_system<parse_separators, format_separator>
{
	template<typename T>
	static T format_abs(tl::span<const string> members) noexcept;
	static void parse_abs(tl::vector<string>& o_elements, const char* path, size_t size) noexcept;
	static bool validate_abs_path(tl::span<const string> members) noexcept;
	static bool match(const char* path, size_t size) noexcept;
};

//////////////////////////////////////////////////////////////////////////

}

//////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////
//////////////////////////////////////////////////////////////////////////

namespace tl
{
//////////////////////////////////////////////////////////////////////////

template <typename... Systems>
template<typename T>
T path_systems<Systems...>::format_abs(int type_id, tl::span<const string> members) noexcept
{
	TL_PLAIN_ASSERT(type_id >= 0, "Error: trying to format an unknown path system type.");
	return detail::path_system::path_system_getter<0, Systems...>::template format_abs<T>(type_id, members);
}

//////////////////////////////////////////////////////////////////////////

template <typename... Systems>
void path_systems<Systems...>::parse_abs(tl::vector<string>& o_elements, int type_id, const char* path, size_t size) noexcept
{
	TL_PLAIN_ASSERT(type_id >= 0, "Error: trying to parse an unknown path system type.");
	detail::path_system::path_system_getter<0, Systems...>::parse_abs(o_elements, type_id, path, size);
}

//////////////////////////////////////////////////////////////////////////

template <typename... Systems>
int path_systems<Systems...>::deduce_system_type(const char* path, size_t size) noexcept
{
	return detail::path_system::path_system_getter<0, Systems...>::deduce_system_type(path, size);
}

//////////////////////////////////////////////////////////////////////////

template <typename... Systems>
bool path_systems<Systems...>::validate_abs_path(int type_id, tl::span<const string> members) noexcept
{
	TL_PLAIN_ASSERT(type_id >= 0, "Error: trying to validate an unknown path system type.");
	return detail::path_system::path_system_getter<0, Systems...>::validate_abs_path(type_id, members);
}

//////////////////////////////////////////////////////////////////////////

template <typename... Systems>
const tl::vector<tl::vector<const char*> >& path_systems<Systems...>::get_all_parse_separators() noexcept
{
	static tl::vector<tl::vector<const char*>> s_all_separators_cache = detail::path_system::path_systems_getter<Systems...>::get_all_parse_separators();
	return s_all_separators_cache;
}

//////////////////////////////////////////////////////////////////////////

template <typename... Systems>
void path_systems<Systems...>::parse_relative(tl::vector<string>& o_elements, const char* path, size_t size) noexcept
{
	const tl::vector<tl::vector<const char*> >& all_separators = get_all_parse_separators();
	const size_t path_system_count = all_separators.size();

	eastl::fixed_vector<string, 512> elements;

	int systemIndex = -1;

	// parse the path
	const char* start = path;
	const char* const end = start + size;
	while (start < end)
	{
		bool matchedSeparator = false;

		const char* sepStart = start;
		const char* sepEnd = nullptr;

		// system hasn't been deduced yet
		if (systemIndex == -1)
		{
			for (size_t s = 0; s < path_system_count; ++s)
			{
				const tl::vector<const char*>& separators = all_separators[s];
				const char* const* separators_begin = separators.data();
				const char* const* separators_end = separators_begin + separators.size();

				matchedSeparator = detail::path_system::find_next_separator(separators_begin, separators_end, sepStart, end, sepEnd);
				if (matchedSeparator)
				{
					systemIndex = (int)s;
					break;
				}
			}
		}
		// path system already deduced
		else
		{
			const tl::vector<const char*>& separators = all_separators[systemIndex];
			const char* const* separators_begin = separators.data();
			const char* const* separators_end = separators_begin + separators.size();

			matchedSeparator = detail::path_system::find_next_separator(separators_begin, separators_end, sepStart, end, sepEnd);
		}

		// if has matched separator
		if (matchedSeparator)
		{
			if (sepStart > start)
				elements.emplace_back(start, sepStart);

			start = sepEnd;
		}
		else
		{
			//get the remainder of the string
			if (*start != 0)
				elements.emplace_back(start);

			break;
		}
	}

	//now reserve the space and move into final place
	o_elements.reserve(o_elements.size() + elements.size());
	for (string& element : elements)
		o_elements.emplace_back(std::move(element));
}

//////////////////////////////////////////////////////////////////////////

template <typename... Systems>
template <typename TypeToCheck>
bool path_systems<Systems...>::is(int type_id) noexcept
{
	return detail::path_system::path_system_type_checker<0, TypeToCheck, Systems...>::is(type_id);
}

//////////////////////////////////////////////////////////////////////////

template<typename root_tag, typename parse_separators, typename format_separator>
template<typename T>
T simple_path_system<root_tag, parse_separators, format_separator>::format_abs(tl::span<const string> members) noexcept
{
	if constexpr (is_same_v<T, string>)
	{
		eastl::string buffer;
		buffer.reserve(8192);
		detail::path_system::simple_format_abs_path(buffer, members, root_tag::value(), format_separator::value());
		return string(buffer.data(), buffer.size());
	}
	else
	{
		T str;
		detail::path_system::simple_format_abs_path(str, members, root_tag::value(), format_separator::value());
		return str;
	}
}

//////////////////////////////////////////////////////////////////////////

template<typename root_tag, typename parse_separators, typename format_separator>
void simple_path_system<root_tag, parse_separators, format_separator>::parse_abs(tl::vector<string>& o_elements, const char* path, size_t size) noexcept
{
	detail::path_system::simple_parse_path(o_elements, path, size, root_tag::value(), parse_separators::vector());
}

//////////////////////////////////////////////////////////////////////////

template<typename root_tag, typename parse_separators, typename format_separator>
bool simple_path_system<root_tag, parse_separators, format_separator>::match(const char* path, size_t size) noexcept
{
	return detail::path_system::simple_match_prefix(path, size, root_tag::value());
}

//////////////////////////////////////////////////////////////////////////

template<typename root_tag, typename parse_separators, typename format_separator>
bool simple_path_system<root_tag, parse_separators, format_separator>::validate_abs_path(tl::span<const string> /*members*/) noexcept
{
	return true;
}

//////////////////////////////////////////////////////////////////////////

}