From a6afeff49313b35a40e86b8a5fb410d397e894ab Mon Sep 17 00:00:00 2001
From: Pasha Bibko <156938226+PashaBibko@users.noreply.github.com>
Date: Sun, 20 Jul 2025 22:34:11 +0100
Subject: [PATCH] Implemented all Lexer errors

---
 Common/{FileRead.h => File.h} | 35 +++++++++++++++++++++++++++++++++++
 Common/LXC.h                  |  2 +-
 LXC/LXC.cpp                   | 16 +++++++++++++---
 Lexer/inc/Lexer.h             |  4 ++--
 Lexer/src/Lexer.cpp           | 10 ++++++----
 example/example.lx            |  2 +-
 6 files changed, 58 insertions(+), 11 deletions(-)
 rename Common/{FileRead.h => File.h} (72%)

diff --git a/Common/FileRead.h b/Common/File.h
similarity index 72%
rename from Common/FileRead.h
rename to Common/File.h
index 7b10b24..3cba78a 100644
--- a/Common/FileRead.h
+++ b/Common/File.h
@@ -64,4 +64,39 @@ namespace LXC::Util
 
 		return contents;
 	}
+
+	// Struct to hold a position within a file //
+	struct FileLocation
+	{
+		unsigned short col;
+		unsigned short line;
+	};
+
+	// Finds the location of a given index within a file //
+	inline bool GetFileLocationAtIndex(FileLocation& location, const std::string& file, __int32 index)
+	{
+		// Returns false if outside the bounds //
+		if (index < 0 || index > file.length())
+			return false;
+
+		// Resets location //
+		location.line = 1;
+		location.col = 1;
+
+		// Finds the location //
+		__int32 localIndex = 0;
+		while (localIndex != index)
+		{
+			if (file[localIndex] == '\n')
+			{
+				location.line += 1;
+				location.col = 0;
+			}
+
+			location.col++;
+			localIndex++;
+		}
+
+		return true;
+	}
 }
diff --git a/Common/LXC.h b/Common/LXC.h
index 019a0fe..2a4cd8a 100644
--- a/Common/LXC.h
+++ b/Common/LXC.h
@@ -7,5 +7,5 @@
 // LXC util files //
 
 #include <Result.h>
-#include <FileRead.h>
+#include <File.h>
 #include <IO.h>
diff --git a/LXC/LXC.cpp b/LXC/LXC.cpp
index 20d431b..92a6c35 100644
--- a/LXC/LXC.cpp
+++ b/LXC/LXC.cpp
@@ -27,8 +27,6 @@ int main(int argc, char** argv)
 		Util::Stop();
 	}
 
-	Util::Log("Succesfully opened source file.");
-
 	// Turns the file contents into a vector of tokens //
 	Util::ReturnVal tokens = Lexer::TokenizeFile(fileContents);
 	if (tokens.Failed()) _UNLIKELY
@@ -36,11 +34,23 @@ int main(int argc, char** argv)
 		// Stores the error for easier access //
 		Lexer::LexerError& err = tokens.Error();
 
+		// Finds the file location of the error //
+		Util::FileLocation location;
+		Util::GetFileLocationAtIndex(location, fileContents, err.index);
+
 		// Prints the error to the console //
 		Util::PrintAs<Util::WHITE>("[LXC] ");
-		Util::Print(src.filename().string());
+		Util::Print(src.filename().string(), '(', location.line, ',', location.col, ')');
 		Util::PrintAs<Util::LIGHT_RED>(" Error: ");
+		Util::Print(Lexer::LexerError::ReasonStr(err.reason));
 
+		if (err.reason == Lexer::LexerError::InvalidCharacter)
+			Util::PrintLn(": {", fileContents.Result()[err.index], '}');
+
+		else
+			Util::PrintLn();
+
+		Util::Log("Error occured in Lexer: ", Lexer::LexerError::ReasonStr(err.reason));
 		Util::Stop();
 	}
 
diff --git a/Lexer/inc/Lexer.h b/Lexer/inc/Lexer.h
index cc1a7fe..d98b523 100644
--- a/Lexer/inc/Lexer.h
+++ b/Lexer/inc/Lexer.h
@@ -40,8 +40,8 @@ namespace LXC::Lexer
 		{
 			static const char* reasons[] =
 			{
-				"Invalid character found in source: ",
-				"Unterminated string literal in source starting at: "
+				"Invalid character found in source",
+				"Unterminated string literal in source"
 			};
 
 			return reasons[reason];
diff --git a/Lexer/src/Lexer.cpp b/Lexer/src/Lexer.cpp
index 93e2a07..3f6a293 100644
--- a/Lexer/src/Lexer.cpp
+++ b/Lexer/src/Lexer.cpp
@@ -104,14 +104,16 @@ namespace LXC::Lexer
 
 			// If an if-statement has not been triggered the character must be invalid //
 			else
-			{
-				return Util::FunctionFail<LexerError>(LexerError::InvalidCharacter, -1);
-			}
+				return Util::FunctionFail<LexerError>(LexerError::InvalidCharacter, ctx.index);
 
 			// Iterates to the next index //
 			ctx.column++;
 			ctx.index++;
-		} 
+		}
+
+		// Checks for an unterminated string literal //
+		if (trackers.inStrLiteral)
+			return Util::FunctionFail<LexerError>(LexerError::UnterminatedStringLiteral, trackers.sectionStart);
 
 		return ctx.out;
 	}
diff --git a/example/example.lx b/example/example.lx
index d6227fa..72dea62 100644
--- a/example/example.lx
+++ b/example/example.lx
@@ -1 +1 @@
-FILE 4 CONTENTS "A" GO B HERE 34 * 5 "ELLO THER"
+FILE 4 CONTENTS "A" GO B HERE 34 5 "ELLO THER"