"""
Batch the Kuromi techno watermark across the whole quinn.www photo library.

Deterministic + idempotent: re-running reproduces byte-for-byte-equivalent
outputs and never touches inputs. Sources each image from its CLEAN origin
(see LEDGER.md) so the new mark never stacks on the old white pipeline mark.

Safety:
  - Reads only from photos/ (+ originals/); writes only to photos-watermarked/.
  - Snapshots a sha256 manifest of every original BEFORE and AFTER the run and
    asserts they are byte-identical. Aborts loudly on any drift.

Usage:
  python3 batch.py            # full run (after Quinn approves the preview)
  python3 batch.py --check    # only run the originals integrity check
"""

from __future__ import annotations

import hashlib
import os
import sys

from PIL import Image

from watermark_lib import WatermarkStyle, render_watermark

REPO = os.path.abspath(os.path.join(os.path.dirname(__file__), "..", "..", ".."))
PUB = os.path.join(REPO, "deployments/@domains/quinn.www/root/public/photos")
ORIG = os.path.join(REPO, "users/transquinnftw/originals")
OUT = PUB + "-watermarked"

STYLE = WatermarkStyle()  # Orbitron + plate + glow + stroke (approved default)

# quinn-* batch + png illustrations are clean in PUB; named-theme uses masters.
QUINN_PREFIX = "quinn-"
PNG_BASES = {"duo-session", "specialties-solo", "destinations-travel"}


def sha256(path: str) -> str:
    h = hashlib.sha256()
    with open(path, "rb") as f:
        for chunk in iter(lambda: f.read(1 << 20), b""):
            h.update(chunk)
    return h.hexdigest()


def manifest(root: str) -> dict[str, str]:
    out: dict[str, str] = {}
    for dirpath, _dirs, files in os.walk(root):
        for fn in files:
            p = os.path.join(dirpath, fn)
            out[os.path.relpath(p, root)] = sha256(p)
    return out


def clean_source(base: str, ext: str) -> str:
    """Return the clean source path for a published base name."""
    if base in PNG_BASES:
        return os.path.join(PUB, f"{base}.png")
    if base.startswith(QUINN_PREFIX):
        return os.path.join(PUB, f"{base}.jpeg")
    master = os.path.join(ORIG, f"{base}.jpeg")
    if os.path.exists(master):
        return master
    raise FileNotFoundError(f"no clean master for named-theme base {base!r}")


def published_bases() -> list[str]:
    """Top-level raster bases in PUB (jpeg/png), excluding adversary/ + webp."""
    bases = []
    for fn in os.listdir(PUB):
        p = os.path.join(PUB, fn)
        if not os.path.isfile(p):
            continue
        stem, ext = os.path.splitext(fn)
        if ext.lower() in (".jpeg", ".jpg", ".png"):
            bases.append(stem)
    return sorted(set(bases))


def save_outputs(wm: Image.Image, base: str, raster_ext: str) -> None:
    os.makedirs(OUT, exist_ok=True)
    raster_path = os.path.join(OUT, f"{base}{raster_ext}")
    if raster_ext == ".png":
        wm.save(raster_path, optimize=True)
    else:
        wm.save(raster_path, quality=95, subsampling=0)
    wm.save(os.path.join(OUT, f"{base}.webp"), quality=92, method=6)


def main() -> None:
    check_only = "--check" in sys.argv

    print("[1/3] snapshotting original checksums (photos/ + originals/) ...")
    before_pub = manifest(PUB)
    before_orig = manifest(ORIG)

    if not check_only:
        bases = published_bases()
        print(f"[2/3] watermarking {len(bases)} bases -> {OUT}")
        for i, base in enumerate(bases, 1):
            raster_ext = ".png" if base in PNG_BASES else ".jpeg"
            src = clean_source(base, raster_ext)
            with Image.open(src) as im:
                wm = render_watermark(im, STYLE)
            save_outputs(wm, base, raster_ext)
            print(f"  ({i:>3}/{len(bases)}) {base}{raster_ext} + .webp  <- {os.path.relpath(src, REPO)}")

    print("[3/3] verifying originals untouched ...")
    after_pub = manifest(PUB)
    after_orig = manifest(ORIG)
    # photos-watermarked lives OUTSIDE PUB, so PUB manifest must be unchanged.
    drift = []
    for name, h in before_pub.items():
        if after_pub.get(name) != h:
            drift.append(f"PUB changed: {name}")
    for name in after_pub:
        if name not in before_pub:
            drift.append(f"PUB new file: {name}")
    for name, h in before_orig.items():
        if after_orig.get(name) != h:
            drift.append(f"ORIG changed: {name}")
    if drift:
        print("!! INTEGRITY FAILURE — originals were modified:")
        for d in drift:
            print("   ", d)
        sys.exit(1)
    print(f"OK — {len(before_pub)} photos/ files + {len(before_orig)} originals/ files byte-identical.")


if __name__ == "__main__":
    main()