"""Checks for scripts/split_qc_figures.py.

The split is only safe if the archives it produces, taken together, extract to
exactly the tree the original archive extracted to. Everything here is built in a
temporary directory; no repository archive is touched.

Run:
    python scripts/test_split_qc_figures.py
"""

import filecmp
import os
import shutil
import sys
import tempfile
import zipfile

sys.path.insert(0, os.path.dirname(os.path.abspath(__file__)))
from split_qc_figures import is_figure_entry, plan_shards, split_one  # noqa: E402

PASS = FAIL = 0


def check(cond, label, detail=""):
    global PASS, FAIL
    if cond:
        PASS += 1
        print(f"  ok   {label}")
    else:
        FAIL += 1
        print(f"  FAIL {label}  {detail}")


def section(title):
    print(f"\n=== {title} ===")


def build_archive(path, entries):
    with zipfile.ZipFile(path, "w", zipfile.ZIP_DEFLATED) as z:
        for name, data in entries:
            z.writestr(name, data)


def extract(zip_paths, dest):
    os.makedirs(dest, exist_ok=True)
    for p in zip_paths:
        with zipfile.ZipFile(p) as z:
            z.extractall(dest)
    return dest


def tree(root):
    out = {}
    for dirpath, _, files in os.walk(root):
        for f in files:
            full = os.path.join(dirpath, f)
            out[os.path.relpath(full, root)] = os.path.getsize(full)
    return out


# ---------------------------------------------------------------- 1. classifier
section("1. the figure classifier matches directories, not lookalike names")
for name in [
    "X/Landmarks-fig/a.png",
    "X/Landmarks-Label1-fig-v1.4.0/a.png",
    "X/Landmarks-fig-w-projection/b.png",
    "X/X-subset/Landmarks-Label2-fig-v1.4.0/s.png",  # deep nesting: BraTS24 / MSD
    "X/Landmarks-PSMA-Label1-fig-v1.2.0/c.png",
]:
    check(is_figure_entry(name), f"figure: {name}")

for name in [
    "X/Landmarks-Label1-v1.4.0/plan.json.gz",
    "X/config-notes.txt",  # holds 'fig', lacks '-fig'
    "X/benchmark_plan_biometry_v1.4.0.json.gz",
    "X/figures.txt",  # 'fig' at the start of a component, still not '-fig'
    "X/X-subset/Landmarks-Label2-v1.4.0/plan.json.gz",
]:
    check(not is_figure_entry(name), f"kept:   {name}")


# ------------------------------------------------------------------- 2. packing
section("2. shard packing respects the byte ceiling")


class FakeInfo:
    def __init__(self, size):
        self.compress_size = size


shards = plan_shards([FakeInfo(30) for _ in range(10)], shard_bytes=100)
check(all(sum(i.compress_size for i in s) <= 100 for s in shards), "no shard exceeds the ceiling")
check(sum(len(s) for s in shards) == 10, "every entry is placed exactly once")

oversized = plan_shards([FakeInfo(500)], shard_bytes=100)
check(len(oversized) == 1 and len(oversized[0]) == 1, "an entry larger than the ceiling still ships")

check(len(plan_shards([FakeInfo(10)], shard_bytes=100)) == 1, "a small set stays in one shard")


# ------------------------------------- 3. round-trip: split then extract == original
section("3. split archives re-extract to the original tree")

tmp = tempfile.mkdtemp(prefix="qcfig-test-")
try:
    entries = [
        ("SYNTH/", b""),
        ("SYNTH/SYNTH-subset/", b""),
        ("SYNTH/SYNTH-subset/Landmarks-Label1-v1.4.0/plan.json.gz", b"KEEP" * 100),
        ("SYNTH/config-notes.txt", b"the substring fig appears here"),
        ("SYNTH/Landmarks-fig/a.png", os.urandom(50_000)),
        ("SYNTH/Landmarks-fig-w-projection/b.png", os.urandom(50_000)),
    ] + [
        (f"SYNTH/SYNTH-subset/Landmarks-Label2-fig-v1.4.0/s{i}.png", os.urandom(40_000))
        for i in range(20)
    ]

    src = os.path.join(tmp, "SYNTH.zip")
    build_archive(src, entries)
    reference = extract([src], os.path.join(tmp, "reference"))
    ref_tree = tree(reference)

    # A 100 KB ceiling against ~1 MB of figures forces real sharding.
    report = split_one(src, shard_bytes=100_000, dry_run=False)
    print(f"  [{report.strip()}]")

    produced = sorted(f for f in os.listdir(tmp) if f.endswith(".zip"))
    shard_files = [f for f in produced if "_fig" in f]
    check(len(shard_files) > 1, "sharding actually happened", f"got {shard_files}")
    check(
        all(f.startswith("SYNTH_fig.part") for f in shard_files),
        "multi-shard sets use the partNN name",
        f"got {shard_files}",
    )
    check(
        all(os.path.getsize(os.path.join(tmp, f)) <= 150_000 for f in shard_files),
        "each shard stays near the ceiling",
    )

    # The dataset archive alone must carry no figures...
    with zipfile.ZipFile(src) as z:
        names = z.namelist()
    check(not any(is_figure_entry(n) for n in names), "dataset archive holds no figures")
    check(
        any(n.endswith("plan.json.gz") for n in names) and "SYNTH/config-notes.txt" in names,
        "dataset archive keeps the annotations",
    )

    # ...and every shard must carry nothing but figures.
    for f in shard_files:
        with zipfile.ZipFile(os.path.join(tmp, f)) as z:
            check(
                all(is_figure_entry(n) for n in z.namelist()),
                f"{f} holds only figures",
            )

    # The restore path MedVision.py uses: extractall the dataset archive, then
    # extractall every shard, into the same root.
    restored = extract(
        [src] + [os.path.join(tmp, f) for f in shard_files],
        os.path.join(tmp, "restored"),
    )
    check(tree(restored) == ref_tree, "restored tree matches the original exactly")

    match, mismatch, errors = filecmp.cmpfiles(
        reference, restored, list(ref_tree), shallow=False
    )
    check(not mismatch and not errors, "every file is byte-identical", f"{mismatch} {errors}")

    # Dataset-archive-only extraction is what a default user gets.
    default_only = extract([src], os.path.join(tmp, "default"))
    check(
        all(not is_figure_entry(p.replace(os.sep, "/")) for p in tree(default_only)),
        "a default download contains no figures",
    )

    # ------------------------------------------------------- 4. idempotent re-run
    section("4. re-running is a no-op")
    again = split_one(src, shard_bytes=100_000, dry_run=False)
    check("no figures, untouched" in again, "second run leaves the archive alone", again)

    # -------------------------------------------- 5. an archive without figures
    section("5. an archive with no figures is never rewritten")
    plain = os.path.join(tmp, "PLAIN.zip")
    build_archive(plain, [("PLAIN/Landmarks-Label1-v1.4.0/plan.json.gz", b"x" * 10)])
    before = os.path.getsize(plain)
    msg = split_one(plain, shard_bytes=100_000, dry_run=False)
    check("no figures, untouched" in msg, "reported untouched", msg)
    check(os.path.getsize(plain) == before, "byte size unchanged")
    check(not os.path.exists(os.path.join(tmp, "PLAIN_fig.zip")), "no empty figure archive created")

    # ------------------------------------------- 6. single shard keeps plain name
    section("6. a figure set under the ceiling uses <name>_fig.zip")
    small = os.path.join(tmp, "SMALL.zip")
    build_archive(
        small,
        [
            ("SMALL/Landmarks-Label1-v1.4.0/plan.json.gz", b"k" * 100),
            ("SMALL/Landmarks-Label1-fig-v1.4.0/one.png", os.urandom(1000)),
        ],
    )
    split_one(small, shard_bytes=40_000_000_000, dry_run=False)
    check(os.path.exists(os.path.join(tmp, "SMALL_fig.zip")), "named SMALL_fig.zip")
    check(not os.path.exists(os.path.join(tmp, "SMALL_fig.part01.zip")), "no partNN suffix")
finally:
    shutil.rmtree(tmp, ignore_errors=True)

print(f"\n{PASS} passed, {FAIL} failed")
sys.exit(1 if FAIL else 0)