#pragma once

#ifndef EXP_H_62B23520_7C8E_11DE_8A39_0800200C9A66
#define EXP_H_62B23520_7C8E_11DE_8A39_0800200C9A66


#include "regex.h"
#include <string>
#include <ios>
#include "stream.h"

namespace YAML
{
	////////////////////////////////////////////////////////////////////////////////
	// Here we store a bunch of expressions for matching different parts of the file.

	namespace Exp
	{
		// misc
		inline const RegEx& Space() {
			static const RegEx e = RegEx(' ');
			return e;
		}
		inline const RegEx& Tab() {
			static const RegEx e = RegEx('\t');
			return e;
		}
		inline const RegEx& Blank() {
			static const RegEx e = Space() || Tab();
			return e;
		}
		inline const RegEx& Break() {
			static const RegEx e = RegEx('\n') || RegEx("\r\n");
			return e;
		}
		inline const RegEx& BlankOrBreak() {
			static const RegEx e = Blank() || Break();
			return e;
		}
		inline const RegEx& Digit() {
			static const RegEx e = RegEx('0', '9');
			return e;
		}
		inline const RegEx& Alpha() {
			static const RegEx e = RegEx('a', 'z') || RegEx('A', 'Z');
			return e;
		}
		inline const RegEx& AlphaNumeric() {
			static const RegEx e = Alpha() || Digit();
			return e;
		}
		inline const RegEx& Word() {
			static const RegEx e = AlphaNumeric() || RegEx('-');
			return e;
		}
		inline const RegEx& Hex() {
			static const RegEx e = Digit() || RegEx('A', 'F') || RegEx('a', 'f');
			return e;
		}
		// Valid Unicode code points that are not part of c-printable (YAML 1.2, sec. 5.1)
		inline const RegEx& NotPrintable() {
			static const RegEx e = RegEx(0) || 
				RegEx("\x01\x02\x03\x04\x05\x06\x07\x08\x0B\x0C\x7F", REGEX_OR) || 
				RegEx(0x0E, 0x1F) ||
				(RegEx('\xC2') + (RegEx('\x80', '\x84') || RegEx('\x86', '\x9F')));
			return e;
		}
		inline const RegEx& Utf8_ByteOrderMark() {
			static const RegEx e = RegEx("\xEF\xBB\xBF");
			return e;
		}

		// actual tags

		inline const RegEx& DocStart() {
			static const RegEx e = RegEx("---") + (BlankOrBreak() || RegEx());
			return e;
		}
		inline const RegEx& DocEnd() {
			static const RegEx e = RegEx("...") + (BlankOrBreak() || RegEx());
			return e;
		}
		inline const RegEx& DocIndicator() {
			static const RegEx e = DocStart() || DocEnd();
			return e;
		}
		inline const RegEx& BlockEntry() {
			static const RegEx e = RegEx('-') + (BlankOrBreak() || RegEx());
			return e;
		}
		inline const RegEx& Key() {
			static const RegEx e = RegEx('?');
			return e;
		}
		inline const RegEx& KeyInFlow() {
			static const RegEx e = RegEx('?') + BlankOrBreak();
			return e;
		}
		inline const RegEx& Value() {
			static const RegEx e = RegEx(':') + (BlankOrBreak() || RegEx());
			return e;
		}
		inline const RegEx& ValueInFlow() {
			static const RegEx e = RegEx(':') + (BlankOrBreak() || RegEx(",}", REGEX_OR));
			return e;
		}
		inline const RegEx& ValueInJSONFlow() {
			static const RegEx e = RegEx(':');
			return e;
		}
		inline const RegEx Comment() {
			static const RegEx e = RegEx('#');
			return e;
		}
		inline const RegEx& AnchorEnd() {
			static const RegEx e = RegEx("?:,]}%@`", REGEX_OR) || BlankOrBreak();
			return e;
		}
		inline const RegEx& URI() {
			static const RegEx e = Word() || RegEx("#;/?:@&=+$,_.!~*'()[]", REGEX_OR) || (RegEx('%') + Hex() + Hex());
			return e;
		}
		inline const RegEx& Tag() {
			static const RegEx e = Word() || RegEx("#;/?:@&=+$_.~*'", REGEX_OR) || (RegEx('%') + Hex() + Hex());
			return e;
		}

		// Plain scalar rules:
		// . Cannot start with a blank.
		// . Can never start with any of , [ ] { } # & * ! | > \' \" % @ `
		// . In the block context - ? : must be not be followed with a space.
		// . In the flow context ? is illegal and : and - must not be followed with a space.
		inline const RegEx& PlainScalar() {
			static const RegEx e = !(BlankOrBreak() || RegEx(",[]{}#&*!|>\'\"%@`", REGEX_OR) || (RegEx("-?:", REGEX_OR) + Blank()));
			return e;
		}
		inline const RegEx& PlainScalarInFlow() {
			static const RegEx e = !(BlankOrBreak() || RegEx("?,[]{}#&*!|>\'\"%@`", REGEX_OR) || (RegEx("-:", REGEX_OR) + Blank()));
			return e;
		}
		inline const RegEx& EndScalar() {
			static const RegEx e = RegEx(':') + (BlankOrBreak() || RegEx());
			return e;
		}
		inline const RegEx& EndScalarInFlow() {
			static const RegEx e = (RegEx(':') + (BlankOrBreak() || RegEx(",]}", REGEX_OR))) || RegEx(",?[]{}", REGEX_OR);
			return e;
		}

		inline const RegEx& EscSingleQuote() {
			static const RegEx e = RegEx("\'\'");
			return e;
		}
		inline const RegEx& EscBreak() {
			static const RegEx e = RegEx('\\') + Break();
			return e;
		}

		inline const RegEx& ChompIndicator() {
			static const RegEx e = RegEx("+-", REGEX_OR);
			return e;
		}
		inline const RegEx& Chomp() {
			static const RegEx e = (ChompIndicator() + Digit()) || (Digit() + ChompIndicator()) || ChompIndicator() || Digit();
			return e;
		}

		// and some functions
		std::string Escape(Stream& in);
	}

	namespace Keys
	{
		const char Directive = '%';
		const char FlowSeqStart = '[';
		const char FlowSeqEnd = ']';
		const char FlowMapStart = '{';
		const char FlowMapEnd = '}';
		const char FlowEntry = ',';
		const char Alias = '*';
		const char Anchor = '&';
		const char Tag = '!';
		const char LiteralScalar = '|';
		const char FoldedScalar = '>';
		const char VerbatimTagStart = '<';
		const char VerbatimTagEnd = '>';
	}
}

#endif // EXP_H_62B23520_7C8E_11DE_8A39_0800200C9A66