From 156880d430f058bf224a20f91cd945951a852af1 Mon Sep 17 00:00:00 2001
From: drewcassidy <drewcassidy@me.com>
Date: Fri, 9 Apr 2021 01:33:30 -0700
Subject: [PATCH] Add decode command

---
 quicktex/cli/__init__.py |  4 ++--
 quicktex/cli/decode.py   | 42 ++++++++++++++++++++++++++++++++++------
 quicktex/dds.py          | 27 +++++++++++++-------------
 quicktex/image_utils.py  |  5 +----
 4 files changed, 53 insertions(+), 25 deletions(-)

diff --git a/quicktex/cli/__init__.py b/quicktex/cli/__init__.py
index ac236ca..95640ad 100644
--- a/quicktex/cli/__init__.py
+++ b/quicktex/cli/__init__.py
@@ -1,6 +1,6 @@
 import click
-from encode import encode
-from decode import decode
+from quicktex.cli.encode import encode
+from quicktex.cli.decode import decode
 
 
 @click.group()
diff --git a/quicktex/cli/decode.py b/quicktex/cli/decode.py
index d31a881..cb77cbe 100644
--- a/quicktex/cli/decode.py
+++ b/quicktex/cli/decode.py
@@ -1,16 +1,46 @@
 import click
 import io
-import os
+import os.path
+import quicktex.dds as dds
 from PIL import Image
+from pathlib import Path
 
 
 @click.command()
-@click.option('-f', '--flip', type=bool, default=True, show_default=True, help="vertically flip image after converting")
+@click.option('-f', '--flip', help="vertically flip image after converting")
 @click.option('-r', '--remove', help="remove input images after converting")
-@click.option('-o', '--output', help="output file name. Must only specify one input image.")
 @click.option('-s', '--suffix', type=str, default='', help="suffix to append to output file(s).")
-@click.argument('filenames', nargs=-1, type=click.Path(exists=True))
-def decode(flip, remove, output, suffix, filenames):
+@click.option('-x', '--extension',
+              type=str, default='png',
+              help="extension to use for output. ignored if output is a single file. output filetype is deduced from this")
+@click.option('-o', '--output',
+              type=click.Path(exists=True, readable=True), default='.',
+              help="output file name or directory. If outputting to a file, input filenames must be only a single item.")
+@click.argument('filenames',
+                nargs=-1,
+                type=click.Path(exists=True, readable=True))
+def decode(flip, remove, suffix, extension, output, filenames):
     """Decode an input texture file to an image"""
+
+    assert len(filenames) != 0, 'No input files provided.'
+    outpath = Path(output)
+
+    if outpath.is_file():
+        assert len(filenames) == 1, 'Provided an output file with multiple inputs.'
+
+        def make_outpath(p):
+            return outpath
+    else:
+        def make_outpath(p):
+            return outpath / (p.stem + suffix + '.' + extension)
+
     for filename in filenames:
-        assert filename.endswith(".dds"), "Incorrect file extension"
+        filepath = Path(filename)
+        outpath = make_outpath(filepath)
+
+        assert filepath.is_file(), f"{filename} is not a file!"
+        assert filepath.suffix == '.dds', f"{filename} is not a DDS file!"
+
+        ddsfile = dds.read(filepath)
+        image = ddsfile.decode()
+        image.save(outpath)
diff --git a/quicktex/dds.py b/quicktex/dds.py
index bb58041..447752c 100644
--- a/quicktex/dds.py
+++ b/quicktex/dds.py
@@ -5,10 +5,10 @@ import os
 import struct
 import typing
 import quicktex.image_utils
-import quicktex.s3tc.bc1
-import quicktex.s3tc.bc3
-import quicktex.s3tc.bc4
-import quicktex.s3tc.bc5
+import quicktex.s3tc.bc1 as bc1
+import quicktex.s3tc.bc3 as bc3
+import quicktex.s3tc.bc4 as bc4
+import quicktex.s3tc.bc5 as bc5
 from PIL import Image
 
 
@@ -22,10 +22,10 @@ class DDSFormat:
 
 
 dds_formats = [
-    DDSFormat('BC1', quicktex.s3tc.bc1.BC1Texture, quicktex.s3tc.bc1.BC1Encoder, quicktex.s3tc.bc1.BC1Decoder, 'DXT1'),
-    DDSFormat('BC3', quicktex.s3tc.bc3.BC3Texture, quicktex.s3tc.bc3.BC3Encoder, quicktex.s3tc.bc3.BC3Decoder, 'DXT5'),
-    DDSFormat('BC4', quicktex.s3tc.bc4.BC4Texture, quicktex.s3tc.bc4.BC4Encoder, quicktex.s3tc.bc4.BC4Decoder, 'ATI1'),
-    DDSFormat('BC5', quicktex.s3tc.bc5.BC5Texture, quicktex.s3tc.bc5.BC5Encoder, quicktex.s3tc.bc5.BC5Decoder, 'ATI2'),
+    DDSFormat('BC1', bc1.BC1Texture, bc1.BC1Encoder, bc1.BC1Decoder, 'DXT1'),
+    DDSFormat('BC3', bc3.BC3Texture, bc3.BC3Encoder, bc3.BC3Decoder, 'DXT5'),
+    DDSFormat('BC4', bc4.BC4Texture, bc4.BC4Encoder, bc4.BC4Decoder, 'ATI1'),
+    DDSFormat('BC5', bc5.BC5Texture, bc5.BC5Encoder, bc5.BC5Decoder, 'ATI2'),
 ]
 
 
@@ -194,16 +194,17 @@ def read(path: os.PathLike) -> DDSFile:
         dds = DDSFile()
 
         # READ HEADER
-        assert struct.unpack('<I', file.read(4)) == DDSFile.header_bytes, "Incorrect DDS header size."
+        header_bytes = struct.unpack('<I', file.read(4))[0]
+        assert header_bytes == DDSFile.header_bytes, "Incorrect DDS header size."
 
-        dds.flags = DDSFlags(struct.unpack('<I', file.read(4)))  # read flags enum
+        dds.flags = DDSFlags(struct.unpack('<I', file.read(4))[0])  # read flags enum
         dds.size = struct.unpack('<2I', file.read(8))[::-1]  # read dimensions
         dds.pitch, dds.depth, dds.mipmap_count = struct.unpack('<3I', file.read(12))
         file.read(44)  # skip 44 unused bytes of data
 
-        assert struct.unpack('<I', file.read(4)) == 32, "Incorrect pixel format size."
+        assert struct.unpack('<I', file.read(4))[0] == 32, "Incorrect pixel format size."
 
-        dds.pf_flags = PFFlags(struct.unpack('<I', file.read(4)))
+        dds.pf_flags = PFFlags(struct.unpack('<I', file.read(4))[0])
         dds.four_cc = file.read(4).decode()
         dds.pixel_size, *pixel_bitmasks = struct.unpack('<5I', file.read(20))
 
@@ -235,7 +236,7 @@ def read(path: os.PathLike) -> DDSFile:
             texture = dds.format.texture(*size)  # make a new blocktexture of the current mip size
             nbytes = file.readinto(texture)
 
-            assert nbytes == texture.size, 'Unexpected end of file'
+            assert nbytes == texture.nbytes, 'Unexpected end of file'
 
             dds.textures.append(texture)
 
diff --git a/quicktex/image_utils.py b/quicktex/image_utils.py
index 2c18f0c..edc80f0 100644
--- a/quicktex/image_utils.py
+++ b/quicktex/image_utils.py
@@ -27,11 +27,8 @@ def mip_sizes(dimensions: typing.Tuple[int, int], mip_count: typing.Optional[int
 
     for mip in range(mip_count):
         chain.append(dimensions)
-        dimensions = tuple([max(dim // 2, 1) for dim in dimensions])
-
         if all([dim == 1 for dim in dimensions]):
             break  # we've reached a 1x1 mip and can get no smaller
+        dimensions = tuple([max(dim // 2, 1) for dim in dimensions])
 
     return chain
-
-