Add union parsing support and fix comment handling in struct/union scanners

- Added UnionDecl type to patterns
- Implemented scanUnion() function similar to scanStruct()
- Added writeUnion() code generation
- Updated all switch statements to handle union_decl
- Fixed multi-line comment detection to handle both /* and /**
- Skip empty enums during code generation
- Update dependency resolver to track union field dependencies

lib/sdl3/apigen.py

@@ -1,52 +0,0 @@
-import os
-import time
-import json
-import subprocess
-
-class HeaderParser:
-
-    def __init__(self, headerList, target, headerName):
-        self.headerList = headerList
-        self.path = target
-        self.headerName = headerName
-        self.outputPrefix = "asts/" + headerName
-        self.astJsonFile = os.path.join(orig_dir, self.headerName + ".ast.json")
-        with open(self.astJsonFile) as f:
-            self.jsonRepr = json.load(f)
-
-orig_dir = os.path.abspath(os.path.dirname(__file__))
-inputList = []
-
-def parseAll(sdl3IncludePath, headerList):
-    parsedList = []
-    for f in headerList:
-        if f.endswith(".h"):
-            headerName = f.split(".")[0]
-            if "_" in headerName:
-                headerName = headerName.split('_')[1]
-
-            print(headerName)
-            parsedList.append(os.path.join(sdl3IncludePath, f))
-            parsePath =  os.path.join(sdl3IncludePath, 'SDL_gpu.h')
-            # os.system(f"cheader2json convert {f} --prefix={self.headerName}")
-
-def parse():
-    global inputList
-    sdl3IncludePath = os.path.join(orig_dir, 'SDL/include/SDL3')
-    discoveredFiles = os.listdir(os.path.join(orig_dir, 'SDL/include/SDL3'))
-
-    parsedList = []
-
-    parseAll(sdl3IncludePath, discoveredFiles)
-
-    sdlHeaderList = []
-    for file in discoveredFiles:
-        sdlHeaderList.append(os.path.join(sdl3IncludePath, file))
-
-    parsed = HeaderParser(sdlHeaderList, os.path.join(sdl3IncludePath, 'SDL_gpu.h'), "gpu")
-
-    print("parsing list: ", inputList)
-
-if __name__ == "__main__":
-    while True:
-        parse()

lib/sdl3/parser/SDL_VIDEO_ANALYSIS.md

@@ -0,0 +1,135 @@
+# SDL_video.h Parsing Analysis
+
+## Current Status: ✅ MOSTLY WORKING
+
+The SDL_video.h header parses successfully with only minor missing type warnings. All major functionality is captured.
+
+## Statistics
+
+- **Total declarations found**: 124
+  - Opaque types: 2
+  - Typedefs: 6
+  - Function pointers: 0
+  - Enums: 4
+  - Structs: 2
+  - Flags: 1
+  - Functions: 109
+
+## Successfully Resolved Dependencies
+
+The parser successfully resolves and imports these types from dependency headers:
+
+✅ **SDL_PixelFormat** (from SDL_pixels.h)
+✅ **SDL_Point** (from SDL_rect.h)
+✅ **SDL_Rect** (from SDL_rect.h)
+✅ **SDL_Surface** (from SDL_surface.h)
+✅ **SDL_PropertiesID** (from SDL_properties.h)
+
+## Missing Type Definitions (7 types)
+
+These types are referenced but not found in the included headers:
+
+### 1. EGL-Related Types (5 types)
+
+These are OpenGL ES/EGL integration types defined within SDL_video.h itself:
+
+- **SDL_EGLConfig** - `typedef void *SDL_EGLConfig;`
+- **SDL_EGLDisplay** - `typedef void *SDL_EGLDisplay;`
+- **SDL_EGLSurface** - `typedef void *SDL_EGLSurface;`
+- **SDL_EGLAttribArrayCallback** - Function pointer typedef
+- **SDL_EGLIntArrayCallback** - Function pointer typedef
+
+**Root Cause**: These are defined in SDL_video.h but the parser's typedef scanner is not picking them up properly.
+
+**Issue**: The typedef scanner currently only processes simple typedefs and doesn't handle:
+- Pointer typedefs (`typedef void *Type;`)
+- Function pointer typedefs with complex signatures
+
+### 2. OpenGL Types (2 types)
+
+- **SDL_GLAttr** - Enum type for GL attributes
+- **SDL_GLContext** - `typedef struct SDL_GLContextState *SDL_GLContext;`
+
+**Root Cause**: Similar to EGL types - these are typedef'd in SDL_video.h but not captured by the scanner.
+
+### 3. Callback Types (1 type)
+
+- **SDL_HitTest** - `typedef SDL_HitTestResult (SDLCALL *SDL_HitTest)(...);`
+
+**Root Cause**: Function pointer typedef with calling convention modifier.
+
+### 4. Generic Types (1 type)
+
+- **SDL_FunctionPointer** - `typedef void (SDLCALL *SDL_FunctionPointer)(void);`
+
+**Root Cause**: Function pointer typedef.
+
+## Implementation Plan
+
+### Phase 1: Enhance Typedef Scanner ✅ PRIORITY
+
+**Goal**: Make the typedef scanner capture all typedef forms in the same file being parsed.
+
+**Tasks**:
+
+1. **Add pointer typedef support**
+   ```c
+   typedef void *SDL_EGLConfig;
+   typedef struct SDL_GLContextState *SDL_GLContext;
+   ```
+   - Pattern: `typedef <type> *<name>;`
+   - Store as opaque pointer type
+
+2. **Add function pointer typedef support**
+   ```c
+   typedef SDL_HitTestResult (SDLCALL *SDL_HitTest)(SDL_Window *win, const SDL_Point *area, void *data);
+   typedef void (SDLCALL *SDL_FunctionPointer)(void);
+   ```
+   - Pattern: `typedef <return> (SDLCALL *<name>)(<params>);`
+   - Store as function pointer type with signature
+
+3. **Add enum typedef support**
+   ```c
+   typedef enum SDL_GLAttr { ... } SDL_GLAttr;
+   ```
+   - Pattern: Already handled, but verify it works for GL types
+
+**Implementation Location**: `src/dependency_resolver.zig` - `scanFileForTypedefs()`
+
+**Expected Result**: After this phase, all 7 missing types should be found and properly typed.
+
+### Phase 2: Test and Validate
+
+1. Run parser on SDL_video.h
+2. Verify all 14 originally missing types are now resolved (7 from deps, 7 from typedefs)
+3. Verify generated Zig code compiles
+4. Check that function signatures using these types are correct
+
+### Phase 3: Apply to Other Headers
+
+Once SDL_video.h parses completely clean, apply the same pattern to other headers with similar issues.
+
+## Error Categories
+
+### Category A: Typedef Scanner Limitations ⭐ PRIMARY ISSUE
+- **Impact**: 7/14 missing types (50%)
+- **Difficulty**: Medium
+- **Files affected**: SDL_video.h, potentially others
+- **Solution**: Enhance typedef scanner (Phase 1)
+
+### Category B: Cross-header Dependencies ✅ SOLVED
+- **Impact**: 7/14 missing types (50%) - but these work!
+- **Difficulty**: N/A (already working)
+- **Solution**: Existing dependency resolver handles this correctly
+
+## Success Metrics
+
+After implementing Phase 1:
+- ⬜ Zero "Could not find definition" warnings for SDL_video.h
+- ⬜ Generated code compiles without errors
+- ⬜ All 124 declarations properly typed
+- ⬜ Can use as template for other complex headers
+
+## Notes
+
+The current parsing system is quite robust. The main gap is in the typedef scanner not recognizing all forms of typedef. This is a focused, solvable problem that will unlock SDL_video.h and similar headers.

lib/sdl3/parser/src/codegen.zig

@@ -99,6 +99,7 @@ pub const CodeGen = struct {
                 .function_pointer_decl => |func_ptr_decl| try self.writeFunctionPointer(func_ptr_decl),
                 .enum_decl => |enum_decl| try self.writeEnum(enum_decl),
                 .struct_decl => |struct_decl| try self.writeStruct(struct_decl),
+                .union_decl => |union_decl| try self.writeUnion(union_decl),
                 .flag_decl => |flag_decl| try self.writeFlags(flag_decl),
                 .function_decl => |func| {
                     // Only write standalone functions (not methods)
@@ -206,6 +207,11 @@ pub const CodeGen = struct {
     }
 
     fn writeEnum(self: *CodeGen, enum_decl: EnumDecl) !void {
+        // Skip empty enums
+        if (enum_decl.values.len == 0) {
+            return;
+        }
+
         const zig_name = naming.typeNameToZig(enum_decl.name);
 
         // Write doc comment if present
@@ -270,6 +276,36 @@ pub const CodeGen = struct {
         try self.output.appendSlice(self.allocator, "};\n\n");
     }
 
+    fn writeUnion(self: *CodeGen, union_decl: patterns.UnionDecl) !void {
+        const zig_name = naming.typeNameToZig(union_decl.name);
+
+        // Write doc comment if present
+        if (union_decl.doc_comment) |doc| {
+            try self.writeDocComment(doc);
+        }
+
+        // pub const Event = extern union {
+        try self.output.writer(self.allocator).print("pub const {s} = extern union {{\n", .{zig_name});
+
+        // Write fields
+        for (union_decl.fields) |field| {
+            const zig_type = try types.convertType(field.type_name, self.allocator);
+            defer self.allocator.free(zig_type);
+
+            if (field.comment) |comment| {
+                try self.output.writer(self.allocator).print("    {s}: {s}, // {s}\n", .{
+                    field.name,
+                    zig_type,
+                    comment,
+                });
+            } else {
+                try self.output.writer(self.allocator).print("    {s}: {s},\n", .{ field.name, zig_type });
+            }
+        }
+
+        try self.output.appendSlice(self.allocator, "};\n\n");
+    }
+
     fn writeFlags(self: *CodeGen, flag_decl: FlagDecl) !void {
         const zig_name = naming.typeNameToZig(flag_decl.name);
 

lib/sdl3/parser/src/dependency_resolver.zig

@@ -57,6 +57,7 @@ pub const DependencyResolver = struct {
                 .function_pointer_decl => |fp| fp.name,
                 .enum_decl => |e| e.name,
                 .struct_decl => |s| s.name,
+                .union_decl => |u| u.name,
                 .flag_decl => |f| f.name,
                 .function_decl => continue,
             };
@@ -84,6 +85,11 @@ pub const DependencyResolver = struct {
                         try self.scanType(field.type_name);
                     }
                 },
+                .union_decl => |union_decl| {
+                    for (union_decl.fields) |field| {
+                        try self.scanType(field.type_name);
+                    }
+                },
                 else => {},
             }
         }
@@ -251,6 +257,7 @@ pub fn extractTypeFromHeader(
             .typedef_decl => |t| t.name,
             .enum_decl => |e| e.name,
             .struct_decl => |s| s.name,
+            .union_decl => |u| u.name,
             .flag_decl => |f| f.name,
             else => continue,
         };
@@ -300,6 +307,13 @@ fn cloneDeclaration(allocator: Allocator, decl: Declaration) !Declaration {
                 .fields = try cloneFields(allocator, s.fields),
             },
         },
+        .union_decl => |u| .{
+            .union_decl = .{
+                .name = try allocator.dupe(u8, u.name),
+                .doc_comment = if (u.doc_comment) |doc| try allocator.dupe(u8, doc) else null,
+                .fields = try cloneFields(allocator, u.fields),
+            },
+        },
         .flag_decl => |f| .{
             .flag_decl = .{
                 .name = try allocator.dupe(u8, f.name),
@@ -407,6 +421,16 @@ fn freeDeclaration(allocator: Allocator, decl: Declaration) void {
             }
             allocator.free(s.fields);
         },
+        .union_decl => |u| {
+            allocator.free(u.name);
+            if (u.doc_comment) |doc| allocator.free(doc);
+            for (u.fields) |field| {
+                allocator.free(field.name);
+                allocator.free(field.type_name);
+                if (field.comment) |c| allocator.free(c);
+            }
+            allocator.free(u.fields);
+        },
         .flag_decl => |f| {
             allocator.free(f.name);
             allocator.free(f.underlying_type);

lib/sdl3/parser/src/parser.zig

@@ -97,6 +97,16 @@ pub fn main() !void {
                     }
                     allocator.free(struct_decl.fields);
                 },
+                .union_decl => |union_decl| {
+                    allocator.free(union_decl.name);
+                    if (union_decl.doc_comment) |doc| allocator.free(doc);
+                    for (union_decl.fields) |field| {
+                        allocator.free(field.name);
+                        allocator.free(field.type_name);
+                        if (field.comment) |c| allocator.free(c);
+                    }
+                    allocator.free(union_decl.fields);
+                },
                 .flag_decl => |flag_decl| {
                     allocator.free(flag_decl.name);
                     allocator.free(flag_decl.underlying_type);
@@ -131,6 +141,7 @@ pub fn main() !void {
     var func_ptr_count: usize = 0;
     var enum_count: usize = 0;
     var struct_count: usize = 0;
+    var union_count: usize = 0;
     var flag_count: usize = 0;
     var func_count: usize = 0;
 
@@ -141,6 +152,7 @@ pub fn main() !void {
             .function_pointer_decl => func_ptr_count += 1,
             .enum_decl => enum_count += 1,
             .struct_decl => struct_count += 1,
+            .union_decl => union_count += 1,
             .flag_decl => flag_count += 1,
             .function_decl => func_count += 1,
         }
@@ -151,6 +163,7 @@ pub fn main() !void {
     std.debug.print("  - Function pointers: {d}\n", .{func_ptr_count});
     std.debug.print("  - Enums: {d}\n", .{enum_count});
     std.debug.print("  - Structs: {d}\n", .{struct_count});
+    std.debug.print("  - Unions: {d}\n", .{union_count});
     std.debug.print("  - Flags: {d}\n", .{flag_count});
     std.debug.print("  - Functions: {d}\n\n", .{func_count});
 
@@ -392,6 +405,16 @@ fn freeDeclDeep(allocator: std.mem.Allocator, decl: patterns.Declaration) void {
             }
             allocator.free(s.fields);
         },
+        .union_decl => |u| {
+            allocator.free(u.name);
+            if (u.doc_comment) |doc| allocator.free(doc);
+            for (u.fields) |field| {
+                allocator.free(field.name);
+                allocator.free(field.type_name);
+                if (field.comment) |c| allocator.free(c);
+            }
+            allocator.free(u.fields);
+        },
         .flag_decl => |f| {
             allocator.free(f.name);
             allocator.free(f.underlying_type);

lib/sdl3/parser/src/patterns.zig

@@ -6,6 +6,7 @@ pub const Declaration = union(enum) {
     opaque_type: OpaqueType,
     enum_decl: EnumDecl,
     struct_decl: StructDecl,
+    union_decl: UnionDecl,
     flag_decl: FlagDecl,
     function_decl: FunctionDecl,
     typedef_decl: TypedefDecl,
@@ -35,6 +36,12 @@ pub const StructDecl = struct {
     doc_comment: ?[]const u8,
 };
 
+pub const UnionDecl = struct {
+    name: []const u8, // SDL_Event
+    fields: []FieldDecl,
+    doc_comment: ?[]const u8,
+};
+
 pub const FieldDecl = struct {
     name: []const u8, // x
     type_name: []const u8, // float
@@ -111,6 +118,8 @@ pub const Scanner = struct {
                 try decls.append(self.allocator, .{ .enum_decl = enum_decl });
             } else if (try self.scanStruct()) |struct_decl| {
                 try decls.append(self.allocator, .{ .struct_decl = struct_decl });
+            } else if (try self.scanUnion()) |union_decl| {
+                try decls.append(self.allocator, .{ .union_decl = union_decl });
             } else if (try self.scanFlagTypedef()) |flag_decl| {
                 // Flag typedef must come before simple typedef
                 try decls.append(self.allocator, .{ .flag_decl = flag_decl });
@@ -500,12 +509,12 @@ pub const Scanner = struct {
         while (lines.next()) |line| {
             const trimmed = std.mem.trim(u8, line, " \t\r");
             
-            // Track multi-line comments
-            if (std.mem.indexOf(u8, trimmed, "/**")) |_| {
+            // Track multi-line comments (both /** and /*)
+            if (std.mem.indexOf(u8, trimmed, "/*") != null) {
                 in_multiline_comment = true;
             }
             if (in_multiline_comment) {
-                if (std.mem.indexOf(u8, trimmed, "*/")) |_| {
+                if (std.mem.indexOf(u8, trimmed, "*/") != null) {
                     in_multiline_comment = false;
                 }
                 continue;
@@ -514,7 +523,6 @@ pub const Scanner = struct {
             // Skip comment/bracket/preprocessor lines
             if (trimmed.len == 0) continue;
             if (std.mem.startsWith(u8, trimmed, "//")) continue;
-            if (std.mem.startsWith(u8, trimmed, "/*")) continue;
             if (std.mem.startsWith(u8, trimmed, "*")) continue;
             if (std.mem.startsWith(u8, trimmed, "#")) continue;
             
@@ -542,6 +550,85 @@ pub const Scanner = struct {
         };
     }
 
+    fn scanUnion(self: *Scanner) !?UnionDecl {
+        const start = self.pos;
+
+        if (!self.matchPrefix("typedef union ")) {
+            return null;
+        }
+
+        // Find the opening brace and extract the name before it
+        const name_start = self.pos;
+        while (self.pos < self.source.len and self.source[self.pos] != '{') {
+            self.pos += 1;
+        }
+
+        if (self.pos >= self.source.len) {
+            // No opening brace found - this is an opaque type, not a union
+            self.pos = start;
+            return null;
+        }
+
+        // Extract name from between "typedef union " and "{"
+        const name_slice = std.mem.trim(u8, self.source[name_start..self.pos], " \t\n\r");
+        var iter = std.mem.tokenizeScalar(u8, name_slice, ' ');
+        const name = iter.next() orelse {
+            self.pos = start;
+            return null;
+        };
+
+        // Now we're at the opening brace, read the braced block
+        const body = try self.readBracedBlock();
+        defer self.allocator.free(body);
+
+        // Parse fields
+        var fields = try std.ArrayList(FieldDecl).initCapacity(self.allocator, 20);
+        var lines = std.mem.splitScalar(u8, body, '\n');
+        var in_multiline_comment = false;
+        
+        while (lines.next()) |line| {
+            const trimmed = std.mem.trim(u8, line, " \t\r");
+            
+            // Track multi-line comments (both /** and /*)
+            if (std.mem.indexOf(u8, trimmed, "/*") != null) {
+                in_multiline_comment = true;
+            }
+            if (in_multiline_comment) {
+                if (std.mem.indexOf(u8, trimmed, "*/") != null) {
+                    in_multiline_comment = false;
+                }
+                continue;
+            }
+            
+            // Skip comment/bracket/preprocessor lines
+            if (trimmed.len == 0) continue;
+            if (std.mem.startsWith(u8, trimmed, "//")) continue;
+            if (std.mem.startsWith(u8, trimmed, "*")) continue;
+            if (std.mem.startsWith(u8, trimmed, "#")) continue;
+            
+            // Reuse struct field parsing since unions have same field syntax
+            if (try self.parseStructField(line)) |field| {
+                try fields.append(self.allocator, field);
+            } else {
+                const multi_fields = try self.parseMultiFieldLine(line);
+                if (multi_fields.len > 0) {
+                    for (multi_fields) |field| {
+                        try fields.append(self.allocator, field);
+                    }
+                    self.allocator.free(multi_fields);
+                }
+            }
+        }
+
+        const doc = self.consumePendingDocComment();
+
+        return UnionDecl{
+            .name = try self.allocator.dupe(u8, name),
+            .fields = try fields.toOwnedSlice(self.allocator),
+            .doc_comment = doc,
+        };
+    }
+
     fn parseStructField(self: *Scanner, line: []const u8) !?FieldDecl {
         const trimmed = std.mem.trim(u8, line, " \t\r");
         if (trimmed.len == 0) return null;

lib/sdl3/v2/events.zig

@@ -1,3 +1,4 @@
+const std = @import("std");
 pub const c = @import("c.zig").c;
 
 pub const Window = opaque {};
@@ -240,11 +241,13 @@ pub inline fn pushEvent(event: ?*Event) bool {
     return c.SDL_PushEvent(event);
 }
 
+pub const EventFilter = *const fn(userdata: ?*anyopaque, event: ?*Event) callconv(.C) bool;
+
 pub inline fn setEventFilter(filter: EventFilter, userdata: ?*anyopaque) void {
     return c.SDL_SetEventFilter(filter, userdata);
 }
 
-pub inline fn getEventFilter(filter: ?*EventFilter, userdata: void **) bool {
+pub inline fn getEventFilter(filter: ?*EventFilter, userdata: [*c]?*anyopaque) bool {
     return c.SDL_GetEventFilter(filter, userdata);
 }
 

lib/sdl3/v2/gpu.zig

@@ -1,3 +1,4 @@
+const std = @import("std");
 pub const c = @import("c.zig").c;
 
 pub const FColor = extern struct {

lib/sdl3/v2/keyboard.zig

@@ -1,3 +1,4 @@
+const std = @import("std");
 pub const c = @import("c.zig").c;
 
 pub const Scancode = enum(c_int) {
@@ -180,7 +181,6 @@ pub const Scancode = enum(c_int) {
     scancodeLshift,
     scancodeRctrl,
     scancodeRshift,
-    scancodeMediaSelect,
 };
 
 pub const Window = opaque {

lib/sdl3/v2/video.zig

@@ -1,3 +1,4 @@
+const std = @import("std");
 pub const c = @import("c.zig").c;
 
 pub const PixelFormat = enum(c_int) {