Better errors still

- Actually can print something that underlines a span
 - Resolve imports and use the resolutions during building
 - Doesn't actually make sense to have #checkErrors
 - Simplify some regexes
 - Parse structs

src/main/java/com/jozufozu/flywheel/backend/ShaderSources.java

@@ -89,6 +89,8 @@ public class ShaderSources implements ISelectiveResourceReloadListener {
 				loadProgramSpecs(manager);
 				loadShaderSources(manager);
 
+				shaderSources.values().forEach(SourceFile::resolveIncludes);
+
 				WorldShaderPipeline<WorldProgram> pl = new WorldShaderPipeline<>(this);
 
 				SourceFile source = source(new ResourceLocation(Flywheel.ID, "model.glsl"));

src/main/java/com/jozufozu/flywheel/backend/pipeline/Includer.java

@@ -15,28 +15,25 @@ import net.minecraft.util.ResourceLocation;
 public class Includer {
 
 	public static List<SourceFile> recurseIncludes(SourceFile from) {
-		ShaderSources sources = from.getParent();
-
 		Set<ResourceLocation> seen = new HashSet<>();
 
 		seen.add(from.name);
 
 		List<SourceFile> out = new ArrayList<>();
 
-		process(sources, seen, out, from);
+		process(seen, out, from);
 
 		return out;
 	}
 
-	private static void process(ShaderSources sources, Set<ResourceLocation> seen, List<SourceFile> out, SourceFile source) {
+	private static void process(Set<ResourceLocation> seen, List<SourceFile> out, SourceFile source) {
 		ImmutableList<Include> includes = source.getIncludes();
 
 		for (Include include : includes) {
 
-			if (seen.add(include.getFile())) {
-				SourceFile file = sources.source(include.getFile());
-
-				process(sources, seen, out, file);
+			SourceFile file = include.getTarget();
+			if (file != null && seen.add(file.name)) {
+				process(seen, out, file);
 
 				out.add(file);
 			}

src/main/java/com/jozufozu/flywheel/backend/pipeline/SourceFile.java

@@ -10,20 +10,23 @@ import java.util.regex.Pattern;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.jozufozu.flywheel.backend.ShaderSources;
+import com.jozufozu.flywheel.backend.pipeline.error.ErrorReporter;
+import com.jozufozu.flywheel.backend.pipeline.parse.AbstractShaderElement;
 import com.jozufozu.flywheel.backend.pipeline.parse.Include;
 import com.jozufozu.flywheel.backend.pipeline.parse.ShaderFunction;
+import com.jozufozu.flywheel.backend.pipeline.parse.ShaderStruct;
 import com.jozufozu.flywheel.backend.pipeline.span.CharPos;
 import com.jozufozu.flywheel.backend.pipeline.span.ErrorSpan;
 import com.jozufozu.flywheel.backend.pipeline.span.Span;
 import com.jozufozu.flywheel.backend.pipeline.span.StringSpan;
+import com.jozufozu.flywheel.util.StringUtil;
 
 import it.unimi.dsi.fastutil.ints.IntArrayList;
 import it.unimi.dsi.fastutil.ints.IntList;
 import net.minecraft.util.ResourceLocation;
 
 public class SourceFile {
-	// #use "valid_namespace:valid/path_to_file.glsl"
-	private static final Pattern includePattern = Pattern.compile("#use \"(\\w+:[\\w./]+)\"");
+	private static final Pattern includePattern = Pattern.compile("#use \"(.*)\"");
 
 	private static final Pattern newLine = Pattern.compile("(\\r\\n|\\r|\\n)");
 
@@ -34,11 +37,13 @@ public class SourceFile {
 
 	private final ShaderSources parent;
 	private final String source;
+	private final ImmutableList<String> lines;
 
 	private final IntList lineStarts;
 
 	// Function name -> Function object
 	private final ImmutableMap<String, ShaderFunction> functions;
+	private final ImmutableMap<String, ShaderStruct> structs;
 
 	// Includes ordered as defined in the source
 	private final ImmutableList<Include> includes;
@@ -51,10 +56,12 @@ public class SourceFile {
 		this.name = name;
 		this.source = source;
 
-		this.lineStarts = getLinePositions();
+		this.lineStarts = createLineStarts();
+		this.lines = createLineList(lineStarts);
 
-		this.functions = parseFunctions();
 		this.includes = parseIncludes();
+		this.functions = parseFunctions();
+		this.structs = parseStructs();
 	}
 
 	public String getSource() {
@@ -73,6 +80,12 @@ public class SourceFile {
 		return includes;
 	}
 
+	public void resolveIncludes() {
+		for (Include include : includes) {
+			include.resolve();
+		}
+	}
+
 	public CharPos getCharPos(int charPos) {
 		int lineNo = 0;
 		for (; lineNo < lineStarts.size(); lineNo++) {
@@ -83,7 +96,9 @@ public class SourceFile {
 			}
 		}
 
-		int lineStart = lineStarts.getInt(lineNo - 1);
+		lineNo -= 1;
+
+		int lineStart = lineStarts.getInt(lineNo);
 
 		return new CharPos(charPos, lineNo, charPos - lineStart);
 	}
@@ -95,7 +110,7 @@ public class SourceFile {
 				.append(name)
 				.append("':\n");
 		int i = 1;
-		for (String s : source.split("\n")) {
+		for (String s : lines) {
 			builder.append(String.format("%1$4s: ", i++))
 					.append(s)
 					.append('\n');
@@ -129,7 +144,7 @@ public class SourceFile {
 	/**
 	 * Scan the source for line breaks, recording the position of the first character of each line.
 	 */
-	private IntList getLinePositions() {
+	private IntList createLineStarts() {
 		IntList l = new IntArrayList();
 		l.add(0); // first line is always at position 0
 
@@ -141,6 +156,19 @@ public class SourceFile {
 		return l;
 	}
 
+	private ImmutableList<String> createLineList(IntList lines) {
+		ImmutableList.Builder<String> builder = ImmutableList.builder();
+
+		for (int i = 1; i < lines.size(); i++) {
+			int start = lines.getInt(i - 1);
+			int end = lines.getInt(i);
+
+			builder.add(StringUtil.trimEnd(source.substring(start, end)));
+		}
+
+		return builder.build();
+	}
+
 	/**
 	 * Scan the source for function definitions and "parse" them into objects that contain properties of the function.
 	 */
@@ -175,6 +203,26 @@ public class SourceFile {
 		return ImmutableMap.copyOf(functions);
 	}
 
+	/**
+	 * Scan the source for function definitions and "parse" them into objects that contain properties of the function.
+	 */
+	private ImmutableMap<String, ShaderStruct> parseStructs() {
+		Matcher matcher = ShaderStruct.struct.matcher(source);
+
+		ImmutableMap.Builder<String, ShaderStruct> functions = ImmutableMap.builder();
+		while (matcher.find()) {
+			Span self = Span.fromMatcher(this, matcher);
+			Span name = Span.fromMatcher(this, matcher, 1);
+			Span body = Span.fromMatcher(this, matcher, 2);
+
+			ShaderStruct shaderStruct = new ShaderStruct(self, name, body);
+
+			functions.put(body.get(), shaderStruct);
+		}
+
+		return functions.build();
+	}
+
 	/**
 	 * Scan the source for <code>#use "..."</code> directives.
 	 * Records the contents of the directive into an {@link Include} object, and marks the directive for elision.
@@ -214,4 +262,12 @@ public class SourceFile {
 
 		return -1;
 	}
+
+	public int getLineCount() {
+		return lines.size();
+	}
+
+	public CharSequence getLine(int lineNo) {
+		return lines.get(lineNo);
+	}
 }

src/main/java/com/jozufozu/flywheel/backend/pipeline/error/ErrorBuilder.java

@@ -1,10 +1,11 @@
 package com.jozufozu.flywheel.backend.pipeline.error;
 
 import com.jozufozu.flywheel.backend.pipeline.SourceFile;
+import com.jozufozu.flywheel.backend.pipeline.span.Span;
 
 public class ErrorBuilder {
 
-	private StringBuilder internal;
+	private final StringBuilder internal = new StringBuilder();
 
 	public ErrorBuilder header(CharSequence msg) {
 		internal.append("error: ")
@@ -18,7 +19,15 @@ public class ErrorBuilder {
 		return endLine();
 	}
 
-	public ErrorBuilder line(int no, CharSequence content) {
+	public ErrorBuilder numberedLine(int no, CharSequence content) {
+		return line(String.valueOf(no), content);
+	}
+
+	public ErrorBuilder line(CharSequence leftColumn, CharSequence rightColumn) {
+
+		internal.append(leftColumn)
+				.append(" | ")
+				.append(rightColumn);
 
 		return endLine();
 	}
@@ -27,4 +36,49 @@ public class ErrorBuilder {
 		internal.append('\n');
 		return this;
 	}
+
+	public ErrorBuilder pointAt(Span span, int ctxLines) {
+		SourceFile file = span.getSourceFile();
+
+		if (span.lines() == 1) {
+
+			int spanLine = span.firstLine();
+
+			int firstLine = Math.max(0, spanLine - ctxLines);
+			int lastLine = Math.min(file.getLineCount(), spanLine + ctxLines);
+
+
+			int firstCol = span.getStart().getCol();
+			int lastCol = span.getEnd().getCol();
+
+			for (int i = firstLine; i <= lastLine; i++) {
+				CharSequence line = file.getLine(i);
+
+				numberedLine(i + 1, line);
+
+				if (i == spanLine) {
+					line(" ", generateUnderline(firstCol, lastCol));
+				}
+			}
+		}
+
+		return this;
+	}
+
+	public CharSequence build() {
+		return internal;
+	}
+
+	public CharSequence generateUnderline(int firstCol, int lastCol) {
+		StringBuilder line = new StringBuilder(lastCol);
+		for (int i = 0; i < firstCol; i++) {
+			line.append(' ');
+		}
+
+		for (int i = firstCol; i < lastCol; i++) {
+			line.append('^');
+		}
+
+		return line;
+	}
 }

src/main/java/com/jozufozu/flywheel/backend/pipeline/error/ErrorReporter.java

@@ -1,16 +1,21 @@
 package com.jozufozu.flywheel.backend.pipeline.error;
 
+import com.jozufozu.flywheel.backend.Backend;
 import com.jozufozu.flywheel.backend.pipeline.SourceFile;
 import com.jozufozu.flywheel.backend.pipeline.span.Span;
 
 public class ErrorReporter {
 
-
-	public String generateSpanError(Span span, String message) {
+	public static void generateSpanError(Span span, String message) {
 		SourceFile file = span.getSourceFile();
 
+		ErrorBuilder builder = new ErrorBuilder();
 
+		CharSequence error = builder.header(message)
+				.errorIn(file)
+				.pointAt(span, 2)
+				.build();
 
-		return "";
+		Backend.log.info(error);
 	}
 }

src/main/java/com/jozufozu/flywheel/backend/pipeline/parse/AbstractShaderElement.java

@@ -1,6 +1,5 @@
 package com.jozufozu.flywheel.backend.pipeline.parse;
 
-import com.jozufozu.flywheel.backend.pipeline.error.ErrorReporter;
 import com.jozufozu.flywheel.backend.pipeline.span.Span;
 
 public abstract class AbstractShaderElement {
@@ -11,5 +10,4 @@ public abstract class AbstractShaderElement {
 		this.self = self;
 	}
 
-	public abstract void checkErrors(ErrorReporter e);
 }

src/main/java/com/jozufozu/flywheel/backend/pipeline/parse/Include.java

@@ -2,6 +2,8 @@ package com.jozufozu.flywheel.backend.pipeline.parse;
 
 import java.util.Optional;
 
+import javax.annotation.Nullable;
+
 import com.jozufozu.flywheel.backend.ShaderSources;
 import com.jozufozu.flywheel.backend.pipeline.error.ErrorReporter;
 import com.jozufozu.flywheel.backend.pipeline.SourceFile;
@@ -14,37 +16,43 @@ public class Include extends AbstractShaderElement {
 	private final ShaderSources sources;
 	private Span file;
 
+	private ResourceLocation fileLoc;
 	private SourceFile resolution;
 
+
 	public Include(ShaderSources sources, Span self, Span file) {
 		super(self);
 		this.sources = sources;
 		this.file = file;
+
+		try {
+			fileLoc = new ResourceLocation(file.get());
+		} catch (RuntimeException error) {
+			ErrorReporter.generateSpanError(file, "malformed source name");
+		}
 	}
 
 	public boolean isResolved() {
 		return resolution != null;
 	}
 
-	public Optional<SourceFile> getTarget() {
-		return Optional.ofNullable(resolution);
+	@Nullable
+	public SourceFile getTarget() {
+		return resolution;
 	}
 
 	public ResourceLocation getFile() {
-		return new ResourceLocation(file.get());
+		return fileLoc;
 	}
 
-	@Override
-	public void checkErrors(ErrorReporter e) {
+	public void resolve() {
 
-		String name = file.get();
+		if (fileLoc == null) return;
 
 		try {
-			ResourceLocation loc = new ResourceLocation(name);
-			resolution = sources.source(loc);
+			resolution = sources.source(fileLoc);
 		} catch (RuntimeException error) {
-
+			ErrorReporter.generateSpanError(file, "could not find source");
 		}
-
 	}
 }

src/main/java/com/jozufozu/flywheel/backend/pipeline/parse/ShaderFunction.java

@@ -61,9 +61,4 @@ public class ShaderFunction extends AbstractShaderElement {
 
 		return type + " " + name + "(" + p + ")";
 	}
-
-	@Override
-	public void checkErrors(ErrorReporter e) {
-
-	}
 }

src/main/java/com/jozufozu/flywheel/backend/pipeline/parse/ShaderStruct.java

@@ -1,5 +1,6 @@
 package com.jozufozu.flywheel.backend.pipeline.parse;
 
+import java.util.Set;
 import java.util.regex.Matcher;
 import java.util.regex.Pattern;
 
@@ -12,8 +13,8 @@ import com.jozufozu.flywheel.backend.pipeline.span.Span;
 
 public class ShaderStruct extends AbstractShaderElement {
 
-	// https://regexr.com/5t207
-	public static final Pattern struct = Pattern.compile("struct\\s+([\\w\\d]*)\\s*\\{([\\w\\d \\t#\\[\\](),;\\n]*)}\\s*;");
+	// https://regexr.com/61rpe
+	public static final Pattern struct = Pattern.compile("struct\\s+([\\w\\d]*)\\s*\\{([\\w\\d\\s,;]*)}\\s*;\\s");
 
 	public final Span name;
 	public final Span body;
@@ -26,18 +27,16 @@ public class ShaderStruct extends AbstractShaderElement {
 		this.name = name;
 		this.body = body;
 		this.fields = parseFields();
+		this.fields2Types = createTypeLookup();
+	}
 
+	private ImmutableMap<String, Span> createTypeLookup() {
 		ImmutableMap.Builder<String, Span> lookup = ImmutableMap.builder();
 		for (StructField field : fields) {
 			lookup.put(field.name.get(), field.type);
 		}
 
-		this.fields2Types = lookup.build();
-	}
-
-	@Override
-	public void checkErrors(ErrorReporter e) {
-
+		return lookup.build();
 	}
 
 	private ImmutableList<StructField> parseFields() {

src/main/java/com/jozufozu/flywheel/backend/pipeline/parse/StructField.java

@@ -8,30 +8,25 @@ import com.jozufozu.flywheel.backend.pipeline.span.Span;
 public class StructField extends AbstractShaderElement {
 	public static final Pattern fieldPattern = Pattern.compile("(\\S+)\\s*(\\S+);");
 
-	public Span name;
 	public Span type;
+	public Span name;
 
-	public StructField(Span self, Span name, Span type) {
+	public StructField(Span self, Span type, Span name) {
 		super(self);
-		this.name = name;
 		this.type = type;
-	}
-
-	public Span getName() {
-		return name;
+		this.name = name;
 	}
 
 	public Span getType() {
 		return type;
 	}
 
+	public Span getName() {
+		return name;
+	}
+
 	@Override
 	public String toString() {
 		return "TaggedField{" + "name='" + name + '\'' + ", type='" + type + '\'' + '}';
 	}
-
-	@Override
-	public void checkErrors(ErrorReporter e) {
-
-	}
 }

src/main/java/com/jozufozu/flywheel/backend/pipeline/parse/Variable.java

@@ -21,9 +21,4 @@ public class Variable extends AbstractShaderElement {
 	public Span getName() {
 		return name;
 	}
-
-	@Override
-	public void checkErrors(ErrorReporter e) {
-
-	}
 }

src/main/java/com/jozufozu/flywheel/backend/pipeline/span/Span.java

@@ -30,6 +30,14 @@ public abstract class Span implements CharSequence {
 		return in;
 	}
 
+	public CharPos getStart() {
+		return start;
+	}
+
+	public CharPos getEnd() {
+		return end;
+	}
+
 	/**
 	 * @return the string index at the (inclusive) beginning of this code segment.
 	 */
@@ -51,6 +59,17 @@ public abstract class Span implements CharSequence {
 		return start == end;
 	}
 
+	/**
+	 * @return how many lines this span spans.
+	 */
+	public int lines() {
+		return end.getLine() - start.getLine() + 1;
+	}
+
+	public int firstLine() {
+		return start.getLine();
+	}
+
 	/**
 	 * Get a span referring to a code segment inside this code segment.
 	 */

src/main/java/com/jozufozu/flywheel/util/StringUtil.java

@@ -0,0 +1,12 @@
+package com.jozufozu.flywheel.util;
+
+public class StringUtil {
+	public static String trimEnd(String value) {
+		int len = value.length();
+		int st = 0;
+		while ((st < len) && Character.isWhitespace(value.charAt(len - 1))) {
+			len--;
+		}
+		return value.substring(0, len);
+	}
+}