Rework Grammar and Parser

Add proper headless binary construction:
	Includes basic validation

Add Error and Warning structs to Parser
Add FileNode pointer getter to Parser
Change all `char8_t*` and `const char8_t` to `const char*` in Parser
Add Parser move operators and Parser deconstructor
Add BufferHandler PIMPL object to Parser
Add UTF-8 file Warning to v2script
Add proper Grammar value retrieval
Add AbstractSyntaxTree for v2script data parser:
	Has compile-time embedded type information accessible at compile-time and runtime
	Has Tab-based print functionality

Fix wrong environment reference for headless construction in SConstruct
Add error retrieval
Add BasicCallbackOStreamBuffer for callback streaming
Add CallbackStreamBuffer for char
Add CallbackWStreamBuffer for wchar_t
Add BasicCallbackStream
Add CallbackStream for char
Add CallbackWStream for wchar_t
Add grammar for events and decisions
Add event_parse to Parser
Add decision_parse to Parser
Add .clang-format
Ignore dirty lexy module
Add CSV parser and grammar:
	Creates std::vector<csv::LineObject> for a list of lines

Add BasicParser and BasicBufferHandler to reduce code reduplication

2 files changed, 126 insertions, 0 deletions

diff --git a/include/openvic-dataloader/csv/LineObject.hpp b/include/openvic-dataloader/csv/LineObject.hpp
new file mode 100644
index 0000000..0494ffb
--- /dev/null
+++ b/include/openvic-dataloader/csv/LineObject.hpp
@@ -0,0 +1,84 @@
+#pragma once
+
+#include <cstddef>
+#include <cstdint>
+#include <functional>
+#include <initializer_list>
+#include <optional>
+#include <string>
+#include <string_view>
+#include <tuple>
+#include <vector>
+
+namespace ovdl::csv {
+	/// LineObject should be able to recognize the differences between:
+	///	Input -> Indexes == ""
+	/// ;;a;b;c;; -> 0,1,5,6+ == ""
+	/// a;b;c -> 3+ == ""
+	/// a;;b;c;; -> 1,4,5+ == ""
+	/// a;b;;c; -> 2,4+ == ""
+	/// a;b;c;; -> 3,4+ == ""
+	/// a;b;c; -> 3+ == ""
+	/// ;a;b;c -> 0,4+ == ""
+	///
+	/// If this is incorrect, please report an issue.
+	class LineObject final : public std::vector<std::tuple<std::uint32_t, std::string>> {
+	public:
+		// Stored position of value
+		using position_type = std::uint32_t;
+		// Value
+		using inner_value_type = std::string;
+		using container_type = std::vector<std::tuple<position_type, inner_value_type>>;
+
+		constexpr LineObject() = default;
+		constexpr LineObject(LineObject&) = default;
+		constexpr LineObject(LineObject&&) = default;
+		constexpr LineObject(const LineObject&) = default;
+
+		constexpr LineObject& operator=(const LineObject& other) = default;
+		constexpr LineObject& operator=(LineObject&& other) = default;
+
+		constexpr ~LineObject() = default;
+
+		constexpr LineObject(std::initializer_list<value_type> pos_and_val) : container_type(pos_and_val) {
+		}
+
+		constexpr LineObject(position_type prefix_end, std::initializer_list<value_type> pos_and_val, position_type suffix_end = 0)
+			: container_type(pos_and_val),
+			  _prefix_end(prefix_end),
+			  _suffix_end(suffix_end) {
+		}
+
+		/// Special Functionality
+		/// Retrieves value, produces "" for empty values
+		constexpr std::string_view get_value_for(std::size_t position) const {
+			if (position <= _prefix_end || position >= _suffix_end) return "";
+			for (const auto& [pos, val] : *this) {
+				if (pos == position) return val;
+			}
+			return "";
+		}
+		/// Tries to retrieve reference, produces nullopt for empty values
+		constexpr std::optional<const std::reference_wrapper<const std::string>> try_get_string_at(std::size_t position) const {
+			if (position <= _prefix_end || position > _suffix_end) return std::nullopt;
+			for (const auto& [pos, val] : *this) {
+				if (pos == position) return std::cref(val);
+			}
+			return std::nullopt;
+		}
+
+		constexpr position_type prefix_end() const { return _prefix_end; }
+		constexpr void set_prefix_end(position_type value) { _prefix_end = value; }
+
+		constexpr position_type suffix_end() const { return _suffix_end; }
+		constexpr void set_suffix_end(position_type value) { _suffix_end = value; }
+
+		constexpr std::size_t value_count() const { return _suffix_end; }
+
+	private:
+		// Should be position of first valid value on line
+		position_type _prefix_end;
+		// Should be position after last value or position after last seperator
+		position_type _suffix_end;
+	};
+}
\ No newline at end of file
diff --git a/include/openvic-dataloader/csv/Parser.hpp b/include/openvic-dataloader/csv/Parser.hpp
new file mode 100644
index 0000000..3497864
--- /dev/null
+++ b/include/openvic-dataloader/csv/Parser.hpp
@@ -0,0 +1,42 @@
+#pragma once
+
+#include <openvic-dataloader/csv/LineObject.hpp>
+#include <openvic-dataloader/detail/BasicParser.hpp>
+
+namespace ovdl::csv {
+	class Parser final : public detail::BasicParser {
+	public:
+		Parser();
+
+		static Parser from_buffer(const char* data, std::size_t size);
+		static Parser from_buffer(const char* start, const char* end);
+		static Parser from_string(const std::string_view string);
+		static Parser from_file(const char* path);
+		static Parser from_file(const std::filesystem::path& path);
+
+		constexpr Parser& load_from_buffer(const char* data, std::size_t size);
+		constexpr Parser& load_from_buffer(const char* start, const char* end);
+		constexpr Parser& load_from_string(const std::string_view string);
+		constexpr Parser& load_from_file(const char* path);
+		Parser& load_from_file(const std::filesystem::path& path);
+
+		constexpr Parser& load_from_file(const detail::Has_c_str auto& path);
+
+		bool parse_csv();
+
+		const std::vector<csv::LineObject> get_lines() const;
+
+		Parser(Parser&&);
+		Parser& operator=(Parser&&);
+
+		~Parser();
+
+	private:
+		class BufferHandler;
+		std::unique_ptr<BufferHandler> _buffer_handler;
+		std::vector<csv::LineObject> _lines;
+
+		template<typename... Args>
+		constexpr void _run_load_func(detail::LoadCallback<BufferHandler, Args...> auto func, Args... args);
+	};
+}
\ No newline at end of file