[pbm] WIP unit tests.

3 files changed, 155 insertions, 42 deletions

diff --git a/core/image/netpbm/helpers.odin b/core/image/netpbm/helpers.odin
index 5a3000a87..8c5cdd622 100644
--- a/core/image/netpbm/helpers.odin
+++ b/core/image/netpbm/helpers.odin
@@ -14,6 +14,7 @@ destroy :: proc(img: ^image.Image) -> bool {
 	header_destroy(&info.header)
 	free(info)
 	img.metadata = nil
+	free(img)
 
 	return true
 }
diff --git a/core/image/netpbm/netpbm.odin b/core/image/netpbm/netpbm.odin
index 54935d6c6..cccf7e865 100644
--- a/core/image/netpbm/netpbm.odin
+++ b/core/image/netpbm/netpbm.odin
@@ -31,19 +31,19 @@ load :: proc {
 	load_from_buffer,
 }
 
-load_from_file :: proc(filename: string, allocator := context.allocator) -> (img: Image, err: Error) {
+load_from_file :: proc(filename: string, allocator := context.allocator) -> (img: ^Image, err: Error) {
 	context.allocator = allocator
 
 	data, ok := os.read_entire_file(filename); defer delete(data)
 	if !ok {
-		err = .File_Not_Readable
+		err = .Unable_To_Read_File
 		return
 	}
 
-	return read_from_buffer(data)
+	return load_from_buffer(data)
 }
 
-load_from_buffer :: proc(data: []byte, allocator := context.allocator) -> (img: Image, err: Error) {
+load_from_buffer :: proc(data: []byte, allocator := context.allocator) -> (img: ^Image, err: Error) {
 	context.allocator = allocator
 
 	header: Header; defer header_destroy(&header)
@@ -51,7 +51,9 @@ load_from_buffer :: proc(data: []byte, allocator := context.allocator) -> (img:
 	header, header_size = parse_header(data) or_return
 
 	img_data := data[header_size:]
-	img = decode_image(header, img_data) or_return
+
+	img = new(Image)
+	decode_image(img, header, img_data) or_return
 
 	info := new(Info)
 	info.header = header
@@ -69,27 +71,42 @@ save :: proc {
 	save_to_buffer,
 }
 
-save_to_file :: proc(filename: string, img: Image, allocator := context.allocator) -> (err: Error) {
+save_to_file :: proc(filename: string, img: ^Image, custom_info: Info = {}, allocator := context.allocator) -> (err: Error) {
 	context.allocator = allocator
 
 	data: []byte; defer delete(data)
-	data = write_to_buffer(img) or_return
+	data = save_to_buffer(img, custom_info) or_return
 
 	if ok := os.write_entire_file(filename, data); !ok {
-		return .File_Not_Writable
+		return .Unable_To_Write_File
 	}
 
 	return Format_Error.None
 }
 
-save_to_buffer :: proc(img: Image, allocator := context.allocator) -> (buffer: []byte, err: Error) {
+save_to_buffer :: proc(img: ^Image, custom_info: Info = {}, allocator := context.allocator) -> (buffer: []byte, err: Error) {
 	context.allocator = allocator
 
-	info, ok := img.metadata.(^image.Netpbm_Info)
-	if !ok {
-		err = image.General_Image_Error.Invalid_Input_Image
-		return
+	info: Info = {}
+	if custom_info.header.width > 0 {
+		// Custom info has been set, use it.
+		info = custom_info
+	} else {
+		img_info, ok := img.metadata.(^image.Netpbm_Info)
+		if !ok {
+			// image doesn't have .Netpbm info, guess it
+			auto_info, auto_info_found := autoselect_pbm_format_from_image(img)
+			if auto_info_found {
+				info = auto_info
+			} else {
+				return {}, .Invalid_Input_Image
+			}
+		} else {
+			// use info as stored on image
+			info = img_info^
+		}
 	}
+
 	// using info so we can just talk about the header
 	using info
 
@@ -103,11 +120,11 @@ save_to_buffer :: proc(img: Image, allocator := context.allocator) -> (buffer: [
 	if header.format in (PNM + PAM) {
 		if header.maxval <= int(max(u8)) && img.depth != 8 \
 		|| header.maxval > int(max(u8)) && header.maxval <= int(max(u16)) && img.depth != 16 {
-			err = Format_Error.Invalid_Image_Depth
+			err = .Invalid_Image_Depth
 			return
 		}
 	} else if header.format in PFM && img.depth != 32 {
-		err = Format_Error.Invalid_Image_Depth
+		err = .Invalid_Image_Depth
 		return
 	}
 
@@ -233,11 +250,11 @@ save_to_buffer :: proc(img: Image, allocator := context.allocator) -> (buffer: [
 			}
 
 		case:
-			return data.buf[:], Format_Error.Invalid_Image_Depth
+			return data.buf[:], .Invalid_Image_Depth
 		}
 
 	case:
-		return data.buf[:], Format_Error.Invalid_Format
+		return data.buf[:], .Invalid_Format
 	}
 
 	return data.buf[:], Format_Error.None
@@ -263,7 +280,7 @@ parse_header :: proc(data: []byte, allocator := context.allocator) -> (header: H
 		}
 	}
 
-	err = Format_Error.Invalid_Signature
+	err = .Invalid_Signature
 	return
 }
 
@@ -366,7 +383,7 @@ _parse_header_pam :: proc(data: []byte, allocator := context.allocator) -> (head
 
 	// the spec needs the newline apparently
 	if string(data[0:3]) != "P7\n" {
-		err = Format_Error.Invalid_Signature
+		err = .Invalid_Signature
 		return
 	}
 	header.format = .P7
@@ -468,7 +485,7 @@ _parse_header_pfm :: proc(data: []byte) -> (header: Header, length: int, err: Er
 		header.format = .PF
 		header.channels = 3
 	case:
-		err = Format_Error.Invalid_Signature
+		err = .Invalid_Signature
 		return
 	}
 
@@ -531,18 +548,18 @@ _parse_header_pfm :: proc(data: []byte) -> (header: Header, length: int, err: Er
 	return
 }
 
-decode_image :: proc(header: Header, data: []byte, allocator := context.allocator) -> (img: Image, err: Error) {
+decode_image :: proc(img: ^Image, header: Header, data: []byte, allocator := context.allocator) -> (err: Error) {
+	assert(img != nil)
 	context.allocator = allocator
 
-	img = Image {
-		width    = header.width,
-		height   = header.height,
-		channels = header.channels,
-		depth    = header.depth,
-	}
+	img.width    = header.width
+	img.height   = header.height
+	img.channels = header.channels
+	img.depth    = header.depth
 
 	buffer_size := image.compute_buffer_size(img.width, img.height, img.channels, img.depth)
 
+	when false {
 	// we can check data size for binary formats
 	if header.format in BINARY {
 		if header.format == .P4 {
@@ -558,6 +575,7 @@ decode_image :: proc(header: Header, data: []byte, allocator := context.allocato
 			}
 		}
 	}
+	}
 
 	// for ASCII and P4, we use length for the termination condition, so start at 0
 	// BINARY will be a simple memcopy so the buffer length should also be initialised
@@ -665,4 +683,70 @@ decode_image :: proc(header: Header, data: []byte, allocator := context.allocato
 
 	err = Format_Error.None
 	return
+}
+
+// Automatically try to select an appropriate format to save to based on `img.channel` and `img.depth`
+autoselect_pbm_format_from_image :: proc(img: ^Image, prefer_binary := true, force_black_and_white := false, pfm_scale := f32(1.0)) -> (res: Info, ok: bool) {
+	/*
+		PBM (P1, P4): Portable Bit Map,       stores black and white images   (1 channel)
+		PGM (P2, P5): Portable Gray Map,      stores greyscale images         (1 channel, 1 or 2 bytes per value)
+		PPM (P3, P6): Portable Pixel Map,     stores colour images            (3 channel, 1 or 2 bytes per value)
+		PAM (P7    ): Portable Arbitrary Map, stores arbitrary channel images            (1 or 2 bytes per value)
+		PFM (Pf, PF): Portable Float Map,     stores floating-point images    (Pf: 1 channel, PF: 3 channel)
+
+		ASCII   :: Formats{.P1, .P2, .P3}
+	*/
+	using res.header
+
+	width    = img.width
+	height   = img.height
+	channels = img.channels
+	depth    = img.depth
+	maxval   = 255 if img.depth == 8 else 65535
+	little_endian = true if ODIN_ENDIAN == .Little else false
+
+	// Assume we'll find a suitable format
+	ok = true
+
+	switch img.channels {
+	case 1:
+		// Must be Portable Float Map
+		if img.depth == 32 {
+			format = .Pf
+			return
+		}
+
+		if force_black_and_white {
+			// Portable Bit Map
+			format = .P4 if prefer_binary else .P1
+			maxval = 1
+			return
+		} else {
+			// Portable Gray Map
+			format = .P5 if prefer_binary else .P2
+			return
+		}
+
+	case 3:
+		// Must be Portable Float Map
+		if img.depth == 32 {
+			format = .PF
+			return
+		}
+
+		// Portable Pixel Map
+		format = .P6 if prefer_binary else .P3
+		return
+
+	case:
+		// Portable Arbitrary Map
+		if img.depth == 8 || img.depth == 16 {
+			format = .P7
+			scale  = pfm_scale
+			return
+		}
+	}
+
+	// We couldn't find a suitable format
+	return {}, false
 }
\ No newline at end of file
diff --git a/tests/core/image/test_core_image.odin b/tests/core/image/test_core_image.odin
index c328757e4..1ffd3b93d 100644
--- a/tests/core/image/test_core_image.odin
+++ b/tests/core/image/test_core_image.odin
@@ -13,6 +13,7 @@ import "core:testing"
 
 import "core:compress"
 import "core:image"
+import pbm "core:image/netpbm"
 import "core:image/png"
 import "core:image/qoi"
 
@@ -1506,26 +1507,53 @@ run_png_suite :: proc(t: ^testing.T, suite: []PNG_Test) -> (subtotal: int) {
 
 				passed &= test.hash == png_hash
 
-				// Roundtrip through QOI to test the QOI encoder and decoder.
-				if passed && img.depth == 8 && (img.channels == 3 || img.channels == 4) {
-					qoi_buffer: bytes.Buffer
-					defer bytes.buffer_destroy(&qoi_buffer)
-					qoi_save_err := qoi.save(&qoi_buffer, img)
+				if passed {
+					// Roundtrip through QOI to test the QOI encoder and decoder.
+					if img.depth == 8 && (img.channels == 3 || img.channels == 4) {
+						qoi_buffer: bytes.Buffer
+						defer bytes.buffer_destroy(&qoi_buffer)
+						qoi_save_err := qoi.save(&qoi_buffer, img)
 
-					error  = fmt.tprintf("%v test %v QOI save failed with %v.", file.file, count, qoi_save_err)
-					expect(t, qoi_save_err == nil, error)
+						error  = fmt.tprintf("%v test %v QOI save failed with %v.", file.file, count, qoi_save_err)
+						expect(t, qoi_save_err == nil, error)
 
-					if qoi_save_err == nil {
-						qoi_img, qoi_load_err := qoi.load(qoi_buffer.buf[:])
-						defer qoi.destroy(qoi_img)
+						if qoi_save_err == nil {
+							qoi_img, qoi_load_err := qoi.load(qoi_buffer.buf[:])
+							defer qoi.destroy(qoi_img)
 
-						error  = fmt.tprintf("%v test %v QOI load failed with %v.", file.file, count, qoi_load_err)
-						expect(t, qoi_load_err == nil, error)
+							error  = fmt.tprintf("%v test %v QOI load failed with %v.", file.file, count, qoi_load_err)
+							expect(t, qoi_load_err == nil, error)
 
-						qoi_hash := hash.crc32(qoi_img.pixels.buf[:])
-						error  = fmt.tprintf("%v test %v QOI load hash is %08x, expected it match PNG's %08x with %v.", file.file, count, qoi_hash, png_hash, test.options)
-						expect(t, qoi_hash == png_hash, error)
+							qoi_hash := hash.crc32(qoi_img.pixels.buf[:])
+							error  = fmt.tprintf("%v test %v QOI load hash is %08x, expected it match PNG's %08x with %v.", file.file, count, qoi_hash, png_hash, test.options)
+							expect(t, qoi_hash == png_hash, error)
+						}
+					}
+
+					// Roundtrip through PBM to test the PBM encoders and decoders - prefer binary
+					pbm_buf, pbm_save_err := pbm.save_to_buffer(img)
+					defer delete(pbm_buf)
+
+					error = fmt.tprintf("%v test %v PBM save failed with %v.", file.file, count, pbm_save_err)
+					expect(t, pbm_save_err == nil, error)
+
+					if pbm_save_err == nil {
+						// Try to load it again.
+						pbm_img, pbm_load_err := pbm.load(pbm_buf)
+						defer pbm.destroy(pbm_img)
+
+						if pbm_load_err == nil {
+							fmt.printf("%v test %v PBM load worked with %v.\n", file.file, count, pbm_load_err)
+						}
+						error  = fmt.tprintf("%v test %v PBM load failed with %v.", file.file, count, pbm_load_err)
+						expect(t, pbm_load_err == nil, error)
 					}
+
+					// Roundtrip through PBM to test the PBM encoders and decoders - prefer ASCII
+					// pbm_info, pbm_format_selected = pbm.autoselect_pbm_format_from_image(img, false)
+					// fmt.printf("Autoselect PBM: %v (%v)\n", pbm_info, pbm_format_selected)
+
+
 				}
 
 				if .return_metadata in test.options {