Start implementing reading fields from scratch

src/tiff/tiffread.h

@@ -7,19 +7,10 @@ extern "C" {
 
 #include "aliases.h"
 #include "image.h"
+#include <stdbool.h>
 
-#define TAG_MAX_COUNT (UINT16_MAX * sizeof(const char *))
-// Technically, the type parameter is 2-bytes long, but there aren't so many
-// types specified in the spec, so UINT8_MAX should be sufficient
 #define TYPE_MAX_COUNT (UINT8_MAX * sizeof(const char *))
 
-// clang-format off
-enum tiff_byte_order {
-  TIFF_ORDER_LITTLE_ENDIAN = 0x4949,
-  TIFF_ORDER_BIG_ENDIAN    = 0x4d4d,
-};
-// clang-format on
-
 typedef struct hdr TiffHdr;
 struct hdr {
   u16 order;
@@ -27,34 +18,6 @@ struct hdr {
   u32 first_ifd_offset;
 };
 
-// clang-format off
-enum tiff_public_tags {
-  #include "tiff_public_tags.inc"
-};
-
-internal const char *tag_names[TAG_MAX_COUNT] = {
-  #define TIFF_TAG_LOOKUP
-  #include "tiff_public_tags.inc"
-  #undef TIFF_TAG_LOOKUP
-};
-
-enum tiff_field_types {
-  #include "tiff_field_types.inc"
-};
-
-typedef struct field_type TiffFieldType;
-struct field_type {
-  const char *name;
-  u16 byte_count;
-};
-
-internal TiffFieldType field_types[TYPE_MAX_COUNT] = {
-  #define TIFF_TYPE_LOOKUP
-  #include "tiff_field_types.inc"
-  #undef TIFF_TYPE_LOOKUP
-};
-// clang-format on
-
 typedef struct field TiffField;
 struct field {
   u16 tag;
@@ -71,6 +34,45 @@ struct IFD {
 };
 
 // clang-format off
+enum tiff_byte_order {
+  TIFF_ORDER_LITTLE_ENDIAN = 0x4949,
+  TIFF_ORDER_BIG_ENDIAN    = 0x4d4d,
+};
+
+enum tiff_public_tags {
+  #include "tiff_public_tags.inc"
+};
+
+enum tiff_field_types {
+  #include "tiff_field_types.inc"
+};
+
+typedef struct field_type TiffFieldType;
+struct field_type {
+  const char *name;
+  u16 byte_count;
+};
+
+internal TiffFieldType field_types[TYPE_MAX_COUNT] = {
+  #define TIFF_TYPE_LOOKUP
+  #include "tiff_field_types.inc"
+  #undef TIFF_TYPE_LOOKUP
+};
+
+typedef enum tiff_image_type_names {
+  TIFF_IMAGE_TYPE_INVALID   = 0,
+  TIFF_IMAGE_TYPE_BILEVEL   = 1,
+  TIFF_IMAGE_TYPE_GRAYSCALE = TIFF_PUBLIC_TAG_BITS_PER_SAMPLE,
+  TIFF_IMAGE_TYPE_PALETTE   = TIFF_PUBLIC_TAG_BITS_PER_SAMPLE | TIFF_PUBLIC_TAG_COLOR_MAP,
+  TIFF_IMAGE_TYPE_RGB       = TIFF_PUBLIC_TAG_BITS_PER_SAMPLE | TIFF_PUBLIC_TAG_SAMPLES_PER_PIXEL,
+} TiffImageType;
+
+enum tiff_extra_samples {
+  TIFF_EXTRA_SAMPLE_UNSPECIFIED        = 0x0000,
+  TIFF_EXTRA_SAMPLE_ASSOCIATED_ALPHA   = 0x0001,
+  TIFF_EXTRA_SAMPLE_UNASSOCIATED_ALPHA = 0x0002,
+};
+
 enum tiff_compression {
   TIFF_COMPRESSION_UNCOMPRESSED = 0x0001,
   TIFF_COMPRESSION_CCITT_1D     = 0x0002,
@@ -100,6 +102,28 @@ enum tiff_planar_configuration {
 };
 // clang-format on
 
+typedef struct tiff_image TiffImage;
+struct tiff_image {
+  TiffImageType type;
+  u32 image_width;
+  u32 image_length;
+  u32 bits_per_sample;
+  u32 sample_count;
+  bool bits_per_sample_offset;
+  u16 compression;
+  u16 photometric_interpretation;
+  u32 strip_offsets;
+  bool strip_offsets_offset;
+  u32 rows_per_strip;
+  u32 strip_byte_counts;
+  bool strip_byte_counts_offset;
+  u32 strip_count;
+  u32 color_map;
+  u32 extra_samples;
+  u32 extra_samples_count;
+  bool extra_samples_offset;
+};
+
 Image *read_baseline_tiff(const char *file, const Allocator *allocator);
 
 #ifdef __cplusplus