Python wrapper to use image to RGBA Go code

kitty/utils.py

@@ -14,6 +14,7 @@ from functools import lru_cache
 from typing import (
     TYPE_CHECKING,
     Any,
+    BinaryIO,
     Callable,
     Dict,
     Generator,
@@ -33,6 +34,7 @@ from typing import (
 
 from .constants import (
     appname,
+    cache_dir,
     clear_handled_signals,
     config_dir,
     is_macos,
@@ -1223,3 +1225,32 @@ def shlex_split_with_positions(text: str, allow_ansi_quoted_strings: bool = Fals
 
 def timed_debug_print(*a: Any, sep: str = ' ', end: str = '\n') -> None:
     _timed_debug_print(sep.join(map(str, a)) + end)
+
+
+def cached_rgba_file_descriptor_for_image_path(path: str) -> Tuple[int, int, int]:
+    from hashlib import sha256
+    path = os.path.realpath(path, strict=True)
+    src_info = os.stat(path)
+    output_name = sha256(path.encode()).hexdigest() + '.rgba'
+    output_path = os.path.join(cache_dir(), 'rgba', output_name)
+
+    def read_data(f: BinaryIO) -> Tuple[int, int, int]:
+        header = f.read(8)
+        import struct
+        width, height = struct.unpack('<II', header)
+        return width, height, os.dup(f.fileno())
+
+    with suppress(OSError), open(output_path, 'rb') as f:
+        dest_info = os.stat(f.fileno())
+        if dest_info.st_size == src_info.st_size and dest_info.st_mtime >= src_info.st_mtime:
+            return read_data(f)
+
+    import subprocess
+    cp = subprocess.run([kitten_exe(), '__render_image__', path], capture_output=True)
+    if cp.returncode != 0:
+        raise ValueError(f'Failed to convert path to RGBA data with error: {cp.stderr.decode("utf-8", "replace")}')
+    ans = cp.stdout.decode().strip()
+    if ans != output_path:
+        raise ValueError(f'The two cache name algorithms dont agree for path: {path}\n{output_path} != {ans}')
+    with open(ans, 'rb') as f:
+        return read_data(f)