Initial Commit

parser.py

@@ -0,0 +1,177 @@
+"""
+parser.py — Filename parsing and Shot data model.
+
+Filename format:
+    SHOW_EPISODE_SEQUENCE_SHOT_ELEMENT_TASK_VERSION.FRAME.exr
+
+Example:
+    UNG_101_012_010_BG01_TT_v001.01001.exr
+"""
+from __future__ import annotations
+
+import re
+import struct
+from dataclasses import dataclass, field
+from pathlib import Path
+
+
+# ──────────────────────────────────────────────────────────────────────────────
+# Regex patterns
+# ──────────────────────────────────────────────────────────────────────────────
+
+# Matches the basename (no frame, no extension):
+#   SHOW_EPISODE_SEQUENCE_SHOT_ELEMENT_TASK_VERSION
+BASENAME_RE = re.compile(
+    r"^(?P<show>[^_]+)_"
+    r"(?P<episode>[^_]+)_"
+    r"(?P<sequence>[^_]+)_"
+    r"(?P<shot>[^_]+)_"
+    r"(?P<element>[^_]+)_"
+    r"(?P<task>[^_]+)_"
+    r"(?P<version>v\d+)$",
+    re.IGNORECASE,
+)
+
+# Matches a full EXR sequence filename: {basename}.{4-7 digit frame}.exr
+SEQ_FILE_RE = re.compile(r"^(.+)\.(\d{4,7})\.exr$", re.IGNORECASE)
+
+
+# ──────────────────────────────────────────────────────────────────────────────
+# Data model
+# ──────────────────────────────────────────────────────────────────────────────
+
+@dataclass
+class Shot:
+    show: str
+    episode: str
+    sequence: str
+    shot: str
+    element: str
+    task: str
+    version: str
+    basename: str
+    first_frame: int
+    last_frame: int
+    frame_count: int
+    missing_frames: list[int] = field(default_factory=list)
+    width: int = 0
+    height: int = 0
+    input_sequence: str = ""   # Nuke-style path, e.g. /path/basename.%05d.exr
+    output_folder: str = ""
+    output_movie: str = ""
+    output_exr: str = ""
+    status: str = "Ready"
+
+    @property
+    def display_frames(self) -> str:
+        s = f"{self.first_frame}\u2013{self.last_frame}  ({self.frame_count}f)"
+        if self.missing_frames:
+            s += f"  [{len(self.missing_frames)} missing]"
+        return s
+
+    @property
+    def display_resolution(self) -> str:
+        return f"{self.width}\u00d7{self.height}" if self.width and self.height else "\u2014"
+
+
+# ──────────────────────────────────────────────────────────────────────────────
+# Parsing helpers
+# ──────────────────────────────────────────────────────────────────────────────
+
+def parse_basename(basename: str) -> dict | None:
+    """Return a dict of named fields for *basename*, or None if it does not match."""
+    m = BASENAME_RE.match(basename)
+    return m.groupdict() if m else None
+
+
+def build_shot(
+    basename: str,
+    source_dir: str,
+    frames: list[int],
+    output_root: str,
+    parsed: dict,
+    frame_padding: int = 4,
+) -> Shot:
+    """Construct a :class:`Shot` from parsed filename parts and frame list."""
+    frames_sorted = sorted(frames)
+    first = frames_sorted[0]
+    last = frames_sorted[-1]
+    missing = sorted(set(range(first, last + 1)) - set(frames_sorted))
+
+    show = parsed["show"]
+    episode = parsed["episode"]
+
+    # Nuke requires forward slashes even on Windows
+    input_dir = Path(source_dir).as_posix()
+    input_seq = f"{input_dir}/{basename}.%0{frame_padding}d.exr"
+
+    out_folder = Path(output_root) / show / f"{show}_{episode}" / basename
+    out_folder_str = out_folder.as_posix()
+
+    # Attempt to read resolution from the first frame of the sequence
+    first_exr = Path(source_dir) / f"{basename}.{str(first).zfill(frame_padding)}.exr"
+    width, height = read_exr_resolution(str(first_exr))
+
+    return Shot(
+        show=show,
+        episode=episode,
+        sequence=parsed["sequence"],
+        shot=parsed["shot"],
+        element=parsed["element"],
+        task=parsed["task"],
+        version=parsed["version"],
+        basename=basename,
+        first_frame=first,
+        last_frame=last,
+        frame_count=len(frames_sorted),
+        missing_frames=missing,
+        width=width,
+        height=height,
+        input_sequence=input_seq,
+        output_folder=out_folder_str,
+        output_movie=f"{out_folder_str}/{basename}.mov",
+        output_exr=f"{out_folder_str}/{basename}.%0{frame_padding}d.exr",
+    )
+
+
+# ──────────────────────────────────────────────────────────────────────────────
+# EXR header reader (no external dependencies)
+# ──────────────────────────────────────────────────────────────────────────────
+
+_EXR_MAGIC = b"\x76\x2f\x31\x01"
+
+
+def read_exr_resolution(filepath: str) -> tuple[int, int]:
+    """Read (width, height) from an OpenEXR file header without external libraries.
+
+    Returns (0, 0) if the file cannot be read or is not a valid EXR.
+    """
+    try:
+        with open(filepath, "rb") as fh:
+            if fh.read(4) != _EXR_MAGIC:
+                return 0, 0
+            fh.read(4)  # version + feature flags
+            while True:
+                name = _read_cstring(fh)
+                if not name:
+                    break  # end of header
+                type_str = _read_cstring(fh)
+                size = struct.unpack("<I", fh.read(4))[0]
+                data = fh.read(size)
+                if name == "dataWindow" and type_str == "box2i":
+                    xmin, ymin, xmax, ymax = struct.unpack("<iiii", data)
+                    return xmax - xmin + 1, ymax - ymin + 1
+    except Exception:
+        pass
+    return 0, 0
+
+
+def _read_cstring(fh) -> str:
+    """Read a null-terminated ASCII string from a binary file handle."""
+    buf = bytearray()
+    while True:
+        c = fh.read(1)
+        if not c or c == b"\x00":
+            break
+        buf.extend(c)
+    return buf.decode("latin-1")