Initial project import

src/export/edl_writer.py

@@ -0,0 +1,114 @@
+"""
+src/export/edl_writer.py — EditTimeline → CMX 3600 EDL
+
+Generates a standard CMX 3600 Edit Decision List compatible with
+Avid, DaVinci Resolve, Premiere Pro, and most NLEs.
+
+CMX 3600 format reference:
+  https://en.wikipedia.org/wiki/Edit_decision_list#CMX_3600
+"""
+
+from __future__ import annotations
+
+import logging
+from pathlib import Path
+
+from src.core.config import AppConfig
+from src.core.models import EditClip, EditTimeline
+from src.export.timecode import seconds_to_smpte
+
+logger = logging.getLogger(__name__)
+
+
+# ---------------------------------------------------------------------------
+# EDL line builders
+# ---------------------------------------------------------------------------
+
+def _edl_header(title: str) -> str:
+    return f"TITLE: {title}\nFCM: NON-DROP FRAME\n"
+
+
+def _edl_event(
+    event_num: int,
+    clip: EditClip,
+    fps: float,
+) -> str:
+    """
+    Build one CMX 3600 event block for a single clip.
+
+    Format:
+        NNN  AX  V  C  <SRC_IN> <SRC_OUT> <REC_IN> <REC_OUT>
+        * FROM CLIP NAME: ...
+        * COMMENT: ...
+    """
+    src_in  = seconds_to_smpte(clip.match.in_point_s,         fps)
+    source_duration_s = clip.source_timeline_duration_s
+    src_out = seconds_to_smpte(clip.match.in_point_s + source_duration_s, fps)
+    rec_in  = seconds_to_smpte(clip.timeline_start_s,         fps)
+    rec_out = seconds_to_smpte(clip.timeline_start_s + source_duration_s, fps)
+
+    event_line  = f"{event_num:03d}  AX       V     C        {src_in} {src_out} {rec_in} {rec_out}"
+    name_line   = f"* FROM CLIP NAME:  {clip.match.source_path.name}"
+    comment_line = (
+        f"* BEAT {clip.beat.beat_id:03d} | {clip.beat.beat_type.name} | "
+        f"score={clip.match.match_score:.3f}"
+    )
+
+    return "\n".join([event_line, name_line, comment_line, ""])
+
+
+def _edl_black_tail_event(event_num: int, clip: EditClip, fps: float) -> str:
+    rec_in = seconds_to_smpte(clip.timeline_start_s + clip.source_timeline_duration_s, fps)
+    rec_out = seconds_to_smpte(clip.timeline_end_s, fps)
+    event_line = f"{event_num:03d}  BL       V     C        00:00:00:00 00:00:00:00 {rec_in} {rec_out}"
+    comment_line = (
+        f"* BEAT {clip.beat.beat_id:03d} TRAILER-ONLY TAIL | "
+        "add fade/dissolve to black"
+    )
+    return "\n".join([event_line, "* FROM CLIP NAME:  BLACK", comment_line, ""])
+
+
+# ---------------------------------------------------------------------------
+# Public API
+# ---------------------------------------------------------------------------
+
+def write_edl(
+    timeline: EditTimeline,
+    cfg: AppConfig,
+    output_path: Path | None = None,
+) -> Path:
+    """
+    Write the EditTimeline as a CMX 3600 EDL file.
+
+    Args:
+        timeline:    EditTimeline from build_timeline().
+        cfg:         Application configuration.
+        output_path: Override destination. Defaults to
+                     <output_dir>/<project_name>.edl.
+
+    Returns:
+        Path to the written .edl file.
+    """
+    if output_path is None:
+        output_path = cfg.paths.output_dir / f"{timeline.title}.edl"
+
+    output_path.parent.mkdir(parents=True, exist_ok=True)
+
+    fps    = timeline.frame_rate
+    lines  = [_edl_header(timeline.title), "\n"]
+
+    event_num = 1
+    for clip in sorted(timeline.clips, key=lambda c: c.clip_index):
+        lines.append(_edl_event(event_num, clip, fps))
+        event_num += 1
+        if clip.trailer_tail_s > 0:
+            lines.append("\n")
+            lines.append(_edl_black_tail_event(event_num, clip, fps))
+            event_num += 1
+        lines.append("\n")
+
+    edl_text = "\n".join(lines)
+    output_path.write_text(edl_text, encoding="utf-8")
+
+    logger.info("EDL written → %s (%d events)", output_path, timeline.clip_count)
+    return output_path