Merge remote-tracking branch 'origin/current' into feat/docs-llms-txt-current

# Conflicts:
#	docs/conf.py

1 files changed, 344 insertions, 0 deletions

diff --git a/scripts/swap_sources.py b/scripts/swap_sources.py
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--- /dev/null
+++ b/scripts/swap_sources.py
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+#!/usr/bin/env python3
+"""swap_sources.py — Pre-build swap/restore for the RST override mechanism.
+
+In this repo MD is the canonical source for migrated pages. RST kept around
+under the ``rst-<stem>.rst`` prefix is a *fallback* — only consulted when a
+page is explicitly listed in ``docs/_rst_overrides.txt`` to revert to the
+legacy RST rendering.
+
+This script flips the source files in place at build time so Sphinx renders
+the RST instead of the MD for the listed stems, then restores everything
+after the build.
+
+Usage
+-----
+  python scripts/swap_sources.py --swap          # activate RST overrides
+  python scripts/swap_sources.py --restore       # undo activated overrides
+  python scripts/swap_sources.py --dry-run       # show what would be activated
+  python scripts/swap_sources.py --status        # show current state
+  python scripts/swap_sources.py --swap --docs-dir /path/to/docs
+
+The ``--swap`` flag name is kept for backward compatibility with the Makefile
+and Read the Docs config; semantically it now applies RST overrides.
+
+Override list
+-------------
+  docs/_rst_overrides.txt — one stem per line, relative to docs/, comments
+  (#) skipped. Pages listed here render from rst-<stem>.rst instead of
+  <stem>.md at build time.
+
+State files (in docs/_build/, gitignored)
+-----------------------------------------
+  _rst_override_state.json — records completed RST activations
+  _md_exclude.txt          — MD source paths to pass to Sphinx exclude_patterns
+"""
+
+import argparse
+import json
+import os
+import sys
+from pathlib import Path
+
+
+# ---------------------------------------------------------------------------
+# Constants
+# ---------------------------------------------------------------------------
+
+STATE_FILE = "_rst_override_state.json"
+EXCLUDE_FILE = "_md_exclude.txt"
+OVERRIDE_LIST_FILE = "_rst_overrides.txt"
+STATE_VERSION = 2  # bumped from 1 when the swap direction was inverted
+
+
+# ---------------------------------------------------------------------------
+# Core helpers
+# ---------------------------------------------------------------------------
+
+def parse_override_list(path: Path) -> list:
+    """Read *path* and return a list of stems (comments/blanks skipped).
+
+    Returns [] if the file does not exist.
+    """
+    if not path.exists():
+        return []
+    stems = []
+    for line in path.read_text(encoding="utf-8").splitlines():
+        stripped = line.strip()
+        if stripped and not stripped.startswith("#"):
+            stems.append(stripped)
+    return stems
+
+
+def _build_dir(docs_dir: Path) -> Path:
+    build = docs_dir / "_build"
+    build.mkdir(parents=True, exist_ok=True)
+    return build
+
+
+def _state_path(docs_dir: Path) -> Path:
+    return docs_dir / "_build" / STATE_FILE
+
+
+def _exclude_path(docs_dir: Path) -> Path:
+    return docs_dir / "_build" / EXCLUDE_FILE
+
+
+def _resolve_stem_paths(docs_dir: Path, stem: str):
+    """Return (rst_from, rst_to, md_path) as absolute Paths for a given stem."""
+    p = Path(stem)
+    name = p.name
+    parent = p.parent  # may be PosixPath('.')
+    if str(parent) == ".":
+        target_dir = docs_dir
+    else:
+        target_dir = docs_dir / parent
+
+    rst_from = target_dir / f"rst-{name}.rst"  # source: rst-prefixed
+    rst_to = target_dir / f"{name}.rst"        # destination: plain .rst
+    md_path = target_dir / f"{name}.md"        # MD that will be excluded
+    return rst_from, rst_to, md_path
+
+
+# ---------------------------------------------------------------------------
+# do_swap (apply RST overrides)
+# ---------------------------------------------------------------------------
+
+def do_swap(docs_dir: Path) -> None:
+    """Rename rst-{name}.rst → {name}.rst for each stem in _rst_overrides.txt.
+
+    The matching <stem>.md is recorded in _md_exclude.txt so Sphinx ignores it
+    during the build. Validates collisions, records state, writes exclude file.
+    Rolls back all completed renames on any failure.
+    """
+    docs_dir = Path(docs_dir)
+    override_list = parse_override_list(docs_dir / OVERRIDE_LIST_FILE)
+    if not override_list:
+        print("swap_sources: no stems in override list, nothing to do.", file=sys.stderr)
+        return
+
+    # Stale state: warn and auto-restore first
+    state_path = _state_path(docs_dir)
+    if state_path.exists():
+        print(
+            "swap_sources: WARNING — stale override state detected. Auto-restoring before re-applying.",
+            file=sys.stderr,
+        )
+        do_restore(docs_dir)
+
+    # Validate all stems before touching the filesystem
+    planned = []  # list of (rst_from, rst_to, md_path, stem)
+    for stem in override_list:
+        rst_from, rst_to, md_path = _resolve_stem_paths(docs_dir, stem)
+
+        if not rst_from.exists():
+            print(
+                f"swap_sources: skipping {stem!r} — rst- source file not found: {rst_from}",
+                file=sys.stderr,
+            )
+            continue
+
+        if not md_path.exists():
+            print(
+                f"swap_sources: skipping {stem!r} — MD file not found: {md_path}",
+                file=sys.stderr,
+            )
+            continue
+
+        if rst_to.exists():
+            raise RuntimeError(
+                f"collision: both rst- and unprefixed .rst exist for stem {stem!r}. "
+                f"Remove {rst_to} before applying the override."
+            )
+
+        planned.append((rst_from, rst_to, md_path, stem))
+
+    # Execute renames with rollback on failure
+    completed = []  # list of (rst_from, rst_to) that succeeded
+    try:
+        for rst_from, rst_to, md_path, stem in planned:
+            os.rename(rst_from, rst_to)
+            completed.append((rst_from, rst_to))
+    except Exception as exc:
+        # Rollback completed renames in reverse order
+        for from_path, to_path in reversed(completed):
+            try:
+                os.rename(to_path, from_path)
+            except Exception as rollback_exc:
+                print(
+                    f"swap_sources: ROLLBACK ERROR for {to_path}: {rollback_exc}",
+                    file=sys.stderr,
+                )
+        raise RuntimeError(f"swap_sources: rename failed, rolled back. Cause: {exc}") from exc
+
+    if not completed:
+        return
+
+    # Build state and exclude data using relative paths (relative to docs_dir)
+    _build_dir(docs_dir)
+    overrides = []
+    exclude_lines = []
+    for rst_from, rst_to, md_path, stem in planned:
+        rel_from = rst_from.relative_to(docs_dir)
+        rel_to = rst_to.relative_to(docs_dir)
+        rel_md = md_path.relative_to(docs_dir)
+        overrides.append({
+            "stem": stem,
+            "rst_from": str(rel_from),
+            "rst_to": str(rel_to),
+            "md_excluded": str(rel_md),
+        })
+        exclude_lines.append(str(rel_md))
+
+    state = {"version": STATE_VERSION, "overrides": overrides}
+    state_path.write_text(json.dumps(state, indent=2), encoding="utf-8")
+    _exclude_path(docs_dir).write_text("\n".join(exclude_lines) + "\n", encoding="utf-8")
+
+    print(f"swap_sources: applied {len(completed)} RST override(s).", file=sys.stderr)
+
+
+# ---------------------------------------------------------------------------
+# do_restore
+# ---------------------------------------------------------------------------
+
+def do_restore(docs_dir: Path) -> None:
+    """Undo all renames recorded in _rst_override_state.json (reverse order)."""
+    docs_dir = Path(docs_dir)
+    state_path = _state_path(docs_dir)
+
+    if not state_path.exists():
+        return  # no-op
+
+    try:
+        state = json.loads(state_path.read_text(encoding="utf-8"))
+    except (json.JSONDecodeError, OSError) as exc:
+        raise RuntimeError(
+            f"swap_sources: cannot read state file {state_path}: {exc}. "
+            f"Inspect or delete it manually."
+        ) from exc
+
+    version = state.get("version")
+    if version != STATE_VERSION:
+        raise RuntimeError(
+            f"swap_sources: state file version {version!r} does not match "
+            f"expected {STATE_VERSION!r}. Inspect {state_path} manually."
+        )
+
+    overrides = state.get("overrides", [])
+
+    for entry in reversed(overrides):
+        if not isinstance(entry, dict) or "rst_from" not in entry or "rst_to" not in entry:
+            raise RuntimeError(
+                f"swap_sources: malformed entry in {state_path}: {entry!r}. "
+                f"Inspect manually."
+            )
+        rst_from = docs_dir / entry["rst_from"]  # original source (rst-prefixed)
+        rst_to = docs_dir / entry["rst_to"]      # current location (plain .rst)
+        if rst_to.exists():
+            os.rename(rst_to, rst_from)
+        else:
+            print(
+                f"swap_sources: WARNING — expected overridden file not found: {rst_to}",
+                file=sys.stderr,
+            )
+
+    # Clean up state and exclude files
+    state_path.unlink(missing_ok=True)
+    exclude_path = _exclude_path(docs_dir)
+    exclude_path.unlink(missing_ok=True)
+
+    print(f"swap_sources: restored {len(overrides)} RST override(s).", file=sys.stderr)
+
+
+# ---------------------------------------------------------------------------
+# do_dry_run / do_status
+# ---------------------------------------------------------------------------
+
+def do_dry_run(docs_dir: Path) -> None:
+    """Print what would be activated without making any changes."""
+    docs_dir = Path(docs_dir)
+    override_list = parse_override_list(docs_dir / OVERRIDE_LIST_FILE)
+    if not override_list:
+        print("(dry-run) No stems in override list.")
+        return
+
+    for stem in override_list:
+        rst_from, rst_to, md_path = _resolve_stem_paths(docs_dir, stem)
+        issues = []
+        if not rst_from.exists():
+            issues.append("rst- source missing")
+        if not md_path.exists():
+            issues.append("MD missing")
+        if rst_to.exists():
+            issues.append("COLLISION: plain .rst already exists")
+        if issues:
+            print(f"  SKIP  {stem}: {', '.join(issues)}")
+        else:
+            rel_dir = rst_from.parent.relative_to(docs_dir) if rst_from.parent != docs_dir else "."
+            print(f"  APPLY  {rst_from.name} → {rst_to.name}  (in {rel_dir})")
+
+
+def do_status(docs_dir: Path) -> None:
+    """Show current override state."""
+    docs_dir = Path(docs_dir)
+    state_path = _state_path(docs_dir)
+    if not state_path.exists():
+        print("swap_sources: no active RST overrides.")
+        return
+
+    state = json.loads(state_path.read_text(encoding="utf-8"))
+    overrides = state.get("overrides", [])
+    print(f"swap_sources: {len(overrides)} RST override(s) currently active:")
+    for entry in overrides:
+        print(f"  {entry['rst_from']} → {entry['rst_to']}  (excludes {entry['md_excluded']})")
+
+
+# ---------------------------------------------------------------------------
+# CLI
+# ---------------------------------------------------------------------------
+
+def main(argv=None):
+    parser = argparse.ArgumentParser(
+        description="Activate rst-prefixed RST files as the build source for stems "
+                    "listed in docs/_rst_overrides.txt."
+    )
+    group = parser.add_mutually_exclusive_group(required=True)
+    group.add_argument("--swap", action="store_true",
+                       help="Apply RST overrides (rename rst-<stem>.rst → <stem>.rst)")
+    group.add_argument("--restore", action="store_true",
+                       help="Restore original files after a previous --swap")
+    group.add_argument("--dry-run", action="store_true",
+                       help="Show what would be applied")
+    group.add_argument("--status", action="store_true",
+                       help="Show current override state")
+
+    parser.add_argument(
+        "--docs-dir",
+        type=Path,
+        default=None,
+        help="Path to docs/ directory (default: auto-detected from script location)",
+    )
+
+    args = parser.parse_args(argv)
+
+    if args.docs_dir is None:
+        # Default: repo_root/docs where repo_root = parent of scripts/
+        repo_root = Path(__file__).resolve().parent.parent
+        docs_dir = repo_root / "docs"
+    else:
+        docs_dir = args.docs_dir.resolve()
+
+    if not docs_dir.is_dir():
+        parser.error(f"docs directory not found: {docs_dir}")
+
+    if args.swap:
+        do_swap(docs_dir)
+    elif args.restore:
+        do_restore(docs_dir)
+    elif args.dry_run:
+        do_dry_run(docs_dir)
+    elif args.status:
+        do_status(docs_dir)
+
+
+if __name__ == "__main__":
+    main()