#!/usr/bin/env python3
# Ledger — wizard-work/ledger census (Extract lane).
#
# Walks /root/troupe-standup/wizard-work/ledger and emits a machine-verified
# snapshot as three artifacts:
#   ledger-census-2026-10-28.md   # human-readable report with tables
#   ledger-census-2026-10-28.csv  # flat: type, relpath, size, mtime, category
#   ledger-census-2026-10-28.json # structured record (input to the gate)
#
# Measured from the live filesystem (os.stat, no symlink following). The rows
# below are excluded so the census is a stable snapshot of the *data* tree:
#   build_ledger_census.py, verify_ledger_census.py,
#   ledger-census-2026-10-28.md/.csv/.json
import os
import sys
import json
import csv
from collections import Counter
from datetime import datetime, timezone
from pathlib import Path

ROOT = Path("/root/troupe-standup/wizard-work/ledger")
EXCLUDE_DIRS = {"__pycache__", ".git"}
EXCLUDED_NAMES = {
    "build_ledger_census.py",
    "verify_ledger_census.py",
    "ledger-census-2026-10-28.md",
    "ledger-census-2026-10-28.csv",
    "ledger-census-2026-10-28.json",
}
# Category -> extensions (checked in this order).
CATEGORY_RULES = [
    ("script", {".py", ".sh"}),
    ("config", {".yaml", ".yml", ".json", ".toml", ".env", ".lock", ".ini", ".pem"}),
    ("doc", {".md", ".txt"}),
    ("data", {".csv", ".tsv", ".xml", ".db", ".sqlite"}),
    ("media", {".mp3", ".wav", ".png", ".jpg", ".jpeg", ".etag"}),
]


def classify(name: str) -> str:
    suffix = os.path.splitext(name)[1].lower()
    for cat, exts in CATEGORY_RULES:
        if suffix in exts:
            return cat
    return "other"


def main() -> int:
    if not ROOT.is_dir():
        print(f"FATAL: missing {ROOT}", file=sys.stderr)
        return 1

    files = []
    dirs = []
    for dirpath, dirnames, filenames in os.walk(ROOT):
        dirnames.sort()
        dirnames[:] = sorted(d for d in dirnames if d not in EXCLUDE_DIRS)
        for fn in sorted(filenames):
            p = Path(dirpath) / fn
            if p.name in EXCLUDED_NAMES:
                continue
            try:
                st = p.stat()
            except OSError:
                continue
            files.append({
                "type": "file",
                "rel": p.relative_to(ROOT).as_posix(),
                "size": st.st_size,
                "mtime": datetime.fromtimestamp(st.st_mtime, tz=timezone.utc).isoformat(),
                "cat": classify(fn),
            })
        for dn in dirnames:
            dirs.append({
                "type": "dir",
                "rel": os.path.relpath(str(Path(dirpath) / dn), str(ROOT)),
                "size": 0,
                "mtime": "",
                "cat": "dir",
            })

    total_bytes = sum(f["size"] for f in files)
    cat_counts = Counter(f["cat"] for f in files)

    # ---- markdown report ----
    md = []
    w = md.append
    w("# wizard-work/ledger census — 2026-10-28")
    w("")
    w("*source*: os.walk + os.stat over `{}` (no symlink following)".format(ROOT))
    w("*classification*: extension-based per CATEGORY_RULES; row count = files + dirs")
    w("")
    w("## Headline")
    w("")
    w("| measure | value |")
    w("| --- | --- |")
    w("| files | {} |".format(len(files)))
    w("| subdirectories | {} |".format(len(dirs)))
    w("| total entries | {} |".format(len(files) + len(dirs)))
    w("| total bytes | {:,} |".format(total_bytes))
    w("| categories | {} |".format(len(cat_counts)))
    w("")
    w("## Category rollup")
    w("")
    w("| category | files | bytes |")
    w("| --- | --- | --- |")
    for cat in sorted(cat_counts):
        b = sum(f["size"] for f in files if f["cat"] == cat)
        w("| {} | {} | {:,} |".format(cat, cat_counts[cat], b))
    w("")
    w("## File inventory")
    w("")
    w("| category | relpath | size | mtime(UTC) |")
    w("| --- | --- | --- | --- |")
    for f in sorted(files, key=lambda x: (x["cat"], x["rel"])):
        w("| {} | `{}` | {} | {} |".format(f["cat"], f["rel"], f["size"], f["mtime"]))
    w("")
    md_text = "\n".join(md)

    # ---- flat CSV ----
    csv_rows = [["type", "relpath", "size_bytes", "mtime_utc", "category"]]
    for f in sorted(files, key=lambda x: (x["cat"], x["rel"])):
        csv_rows.append([f["type"], f["rel"], str(f["size"]), f["mtime"], f["cat"]])
    csv_text = "\n".join(",".join(csvRow) for csvRow in csv_rows)

    # ---- JSON record ----
    json_obj = {
        "source": str(ROOT),
        "classification_rules": {cat: sorted(exts) for cat, exts in CATEGORY_RULES},
        "excluded_dirs": sorted(EXCLUDE_DIRS),
        "excluded_names": sorted(EXCLUDED_NAMES),
        "counts": {"files": len(files), "dirs": len(dirs), "total_entries": len(files) + len(dirs), "total_bytes": total_bytes},
        "category_counts": {cat: cat_counts.get(cat, 0) for cat in [c for c, _ in CATEGORY_RULES] + ["other"]},
        "files": files,
        "dirs": dirs,
    }

    # ---- write ----
    (ROOT / "ledger-census-2026-10-28.md").write_text(md_text, encoding="utf-8")
    (ROOT / "ledger-census-2026-10-28.csv").write_text(csv_text + "\n", encoding="utf-8")
    (ROOT / "ledger-census-2026-10-28.json").write_text(
        json.dumps(json_obj, indent=2, sort_keys=True) + "\n", encoding="utf-8"
    )

    print("wrote markdown, csv, json")
    print("files={} dirs={} bytes={:,} cats={}".format(
        len(files), len(dirs), total_bytes, dict(sorted(cat_counts.items()))))
    return 0


if __name__ == "__main__":
    sys.exit(main())