#!/usr/bin/env python3
"""
migrate.py  –  One-time reorganisation of the visualization directory.

Run from  D:\\visualization:
    python migrate.py            # full migration + cleanup
    python migrate.py --dry-run  # preview only, no files touched

What the script does
--------------------
1.  Creates:
        data/Sen2_MTC_{New,Old}/GT/        one shared ground-truth copy
        data/Sen2_MTC_{New,Old}/inputs/    cloudy inputs  (_A1 / _A2 / _A3)
        results/Sen2_MTC_{New,Old}/{method}/  per-method predictions

2.  Copies images with a unified naming scheme:
        {id}_real_B.png   →  GT/{id}.png
        {id}_fake_B.png   →  {method}/{id}.png
        Out_{id}.png      →  {method}/{id}.png    (diffcr convention)
        {id}_real_A1.png  →  inputs/{id}_A1.png

3.  After verifying every expected directory is non-empty, deletes the
    original Sen2_MTC_New  and  Sen2_MTC_Old  trees.

Special cases handled
---------------------
- pmaa / Sen2_MTC_New  has no Out/ folder: outputs are extracted from the
  per-sample  test/{psnr_ssim}/  sub-directories.
- diffcr / Sen2_MTC_New  has no test/ folder: Out/ already contains flat
  Out_{id}.png  files.
- diffcr / Sen2_MTC_Old  same as above.
- ctgan / Sen2_MTC_New  has an extra  save/  directory (ignored).
"""

from __future__ import annotations

import argparse
import os
import shutil
import sys
from glob import glob

from tqdm import tqdm

# ---------------------------------------------------------------------------
# Project root  (this file lives directly in  D:\visualization\)
# ---------------------------------------------------------------------------
ROOT = os.path.dirname(os.path.abspath(__file__))

METHODS: list[str] = [
    "ae",
    "crtsnet",
    "ctgan",
    "ddpmcr",
    "diffcr",
    "dsen2cr",
    "mcgan",
    "pix2pix",
    "pmaa",
    "stgan",
    "stnet",
    "uncrtaints",
]

# ---------------------------------------------------------------------------
# Naming helpers
# ---------------------------------------------------------------------------


def strip_id(path: str) -> str:
    """Extract the clean sample ID from any of the naming conventions used.

    Examples
    --------
    T12TUR_R027_0_real_B.png  ->  T12TUR_R027_0
    T12TUR_R027_0_fake_B.png  ->  T12TUR_R027_0
    Out_T12TUR_R027_0.png     ->  T12TUR_R027_0
    GT_T12TUR_R027_0.png      ->  T12TUR_R027_0
    01WFN_60009000_real_B.png ->  01WFN_60009000
    """
    stem = os.path.splitext(os.path.basename(path))[0]

    # Prefix conventions used by diffcr
    for pfx in ("GT_", "Out_"):
        if stem.startswith(pfx):
            return stem[len(pfx) :]

    # Suffix conventions used by most other methods
    for sfx in ("_real_B", "_fake_B"):
        if stem.endswith(sfx):
            return stem[: -len(sfx)]

    # Already a bare ID (should not normally happen)
    return stem


def _copy(src: str, dst: str) -> None:
    """Copy *src* to *dst*, creating parent directories as needed."""
    os.makedirs(os.path.dirname(dst), exist_ok=True)
    shutil.copy2(src, dst)


# ---------------------------------------------------------------------------
# Migration steps
# ---------------------------------------------------------------------------


def migrate_gt(
    src_base: str,
    dst_data: str,
    dry_run: bool,
) -> int:
    """Copy GT images from  ae/GT/  →  data/{dataset}/GT/  with clean names.

    Source name:  {id}_real_B.png
    Dest name:    {id}.png
    """
    src_dir = os.path.join(src_base, "ae", "GT")
    dst_dir = os.path.join(dst_data, "GT")

    files = sorted(glob(os.path.join(src_dir, "*.png")))
    if not files:
        print(f"  [WARN] No GT images found in {src_dir}", file=sys.stderr)
        return 0

    if not dry_run:
        os.makedirs(dst_dir, exist_ok=True)
        for f in tqdm(files, desc="  GT", leave=False):
            _copy(f, os.path.join(dst_dir, strip_id(f) + ".png"))

    return len(files)


def migrate_inputs(
    src_base: str,
    dst_data: str,
    dry_run: bool,
) -> int:
    """Extract  real_A1 / real_A2 / real_A3  from  ae/test/**/
    →  data/{dataset}/inputs/{id}_A{1,2,3}.png

    Source name:  {id}_real_A1.png
    Dest name:    {id}_A1.png
    """
    src_test = os.path.join(src_base, "ae", "test")
    dst_dir = os.path.join(dst_data, "inputs")

    # ae/test/ contains one sub-folder per sample named after its psnr/ssim score.
    files = sorted(glob(os.path.join(src_test, "*", "*_real_A?.png")))
    if not files:
        print(f"  [WARN] No input images found under {src_test}", file=sys.stderr)
        return 0

    if not dry_run:
        os.makedirs(dst_dir, exist_ok=True)
        for f in tqdm(files, desc="  inputs", leave=False):
            # e.g. T12TUR_R027_0_real_A1.png  →  T12TUR_R027_0_A1.png
            new_name = os.path.basename(f).replace("_real_A", "_A")
            _copy(f, os.path.join(dst_dir, new_name))

    return len(files)


def migrate_outputs(
    src_base: str,
    dst_results: str,
    dataset_label: str,
    dry_run: bool,
) -> dict[str, int]:
    """Copy each method's predictions into  results/{dataset}/{method}/{id}.png

    Handles the three different source layouts:
    a) Standard:     method/Out/{id}_fake_B.png
    b) diffcr:       method/Out/Out_{id}.png
    c) pmaa (New):   method/test/{psnr_ssim}/{id}_fake_B.png   (no Out/ folder)
    """
    counts: dict[str, int] = {}

    for method in METHODS:
        src_method = os.path.join(src_base, method)

        if not os.path.isdir(src_method):
            print(f"  SKIP  {dataset_label}/{method}  (directory not found)")
            continue

        dst_dir = os.path.join(dst_results, method)
        files: list[tuple[str, str]] = []  # (src_path, dst_filename)

        # ---- pmaa / Sen2_MTC_New only: no Out/ folder ----------------------
        if method == "pmaa" and "New" in dataset_label:
            for subdir in sorted(glob(os.path.join(src_method, "test", "*/"))):
                for f in sorted(glob(os.path.join(subdir, "*_fake_B.png"))):
                    files.append((f, strip_id(f) + ".png"))

        # ---- all other methods: use the flat Out/ folder -------------------
        else:
            src_out = os.path.join(src_method, "Out")
            if not os.path.isdir(src_out):
                print(
                    f"  SKIP  {dataset_label}/{method}  (Out/ folder not found)",
                    file=sys.stderr,
                )
                continue
            for f in sorted(glob(os.path.join(src_out, "*.png"))):
                files.append((f, strip_id(f) + ".png"))

        if not files:
            print(
                f"  [WARN] {dataset_label}/{method}: no output images found",
                file=sys.stderr,
            )
            counts[method] = 0
            continue

        if not dry_run:
            os.makedirs(dst_dir, exist_ok=True)
            for src_f, dst_name in tqdm(files, desc=f"  {method}", leave=False):
                _copy(src_f, os.path.join(dst_dir, dst_name))

        counts[method] = len(files)

    return counts


# ---------------------------------------------------------------------------
# Verification
# ---------------------------------------------------------------------------


def verify(datasets: list[str]) -> bool:
    """Check that every expected output directory is non-empty."""
    ok = True
    print("\nVerification")
    print("-" * 60)

    for ds in datasets:
        gt_dir = os.path.join(ROOT, "data", ds, "GT")
        n_gt = len(glob(os.path.join(gt_dir, "*.png")))
        status = "OK" if n_gt > 0 else "EMPTY"
        print(f"  data/{ds}/GT          → {n_gt:4d} files  [{status}]")
        if n_gt == 0:
            ok = False

        inp_dir = os.path.join(ROOT, "data", ds, "inputs")
        n_inp = len(glob(os.path.join(inp_dir, "*.png")))
        status = "OK" if n_inp > 0 else "EMPTY"
        print(f"  data/{ds}/inputs      → {n_inp:4d} files  [{status}]")
        if n_inp == 0:
            ok = False

        for m in METHODS:
            d = os.path.join(ROOT, "results", ds, m)
            if os.path.isdir(d):
                n = len(glob(os.path.join(d, "*.png")))
                status = "OK" if n > 0 else "EMPTY"
                print(f"  results/{ds}/{m:<14} → {n:4d} files  [{status}]")
                if n == 0:
                    ok = False
            else:
                print(f"  results/{ds}/{m:<14} → MISSING")
                # Not every method must exist; treat as non-fatal warning.

    return ok


# ---------------------------------------------------------------------------
# Cleanup
# ---------------------------------------------------------------------------


def cleanup(datasets: list[str]) -> None:
    """Delete the original Sen2_MTC_* directories."""
    for ds in datasets:
        old_dir = os.path.join(ROOT, ds)
        if os.path.isdir(old_dir):
            print(f"  Removing {old_dir} …")
            shutil.rmtree(old_dir)
        else:
            print(f"  Already gone: {old_dir}")


# ---------------------------------------------------------------------------
# Main
# ---------------------------------------------------------------------------


def main() -> None:
    ap = argparse.ArgumentParser(
        description="Migrate visualization directory to the cleaned-up layout."
    )
    ap.add_argument(
        "--dry-run",
        action="store_true",
        help="Print a summary of what would happen without touching the filesystem.",
    )
    ap.add_argument(
        "--skip-cleanup",
        action="store_true",
        help="Do not delete the old Sen2_MTC_* directories after migration.",
    )
    ap.add_argument(
        "--dataset",
        type=str,
        default=None,
        choices=["Sen2_MTC_New", "Sen2_MTC_Old"],
        help="Migrate only this dataset (default: both).",
    )
    args = ap.parse_args()

    datasets = [args.dataset] if args.dataset else ["Sen2_MTC_New", "Sen2_MTC_Old"]

    if args.dry_run:
        print("=" * 60)
        print("DRY RUN – no files will be copied or deleted")
        print("=" * 60)

    total_gt = 0
    total_inputs = 0
    total_results: dict[str, dict[str, int]] = {}

    for ds in datasets:
        src_base = os.path.join(ROOT, ds)
        dst_data = os.path.join(ROOT, "data", ds)
        dst_results = os.path.join(ROOT, "results", ds)

        if not os.path.isdir(src_base):
            print(f"\n[ERROR] Source directory not found: {src_base}", file=sys.stderr)
            sys.exit(1)

        print(f"\n{'=' * 60}")
        print(f"  Dataset: {ds}")
        print(f"{'=' * 60}")

        # Ground truth
        print("  Step 1/3 – GT images")
        n_gt = migrate_gt(src_base, dst_data, dry_run=args.dry_run)
        total_gt += n_gt
        print(f"    → {n_gt} GT images {'(would copy)' if args.dry_run else 'copied'}")

        # Input images
        print("  Step 2/3 – Cloudy inputs")
        n_inp = migrate_inputs(src_base, dst_data, dry_run=args.dry_run)
        total_inputs += n_inp
        print(
            f"    → {n_inp} input images ({n_inp // 3 if n_inp else 0} samples × 3) "
            f"{'(would copy)' if args.dry_run else 'copied'}"
        )

        # Per-method outputs
        print("  Step 3/3 – Method outputs")
        counts = migrate_outputs(src_base, dst_results, ds, dry_run=args.dry_run)
        total_results[ds] = counts
        for method, n in counts.items():
            print(
                f"    {method:<14} → {n:4d} images "
                f"{'(would copy)' if args.dry_run else 'copied'}"
            )

    # ---- Summary -----------------------------------------------------------
    print(f"\n{'=' * 60}")
    print("Summary")
    print(f"{'=' * 60}")
    print(f"  GT images   : {total_gt}")
    print(f"  Input images: {total_inputs}")
    for ds, counts in total_results.items():
        total_preds = sum(counts.values())
        print(f"  Results ({ds}): {total_preds}")

    if args.dry_run:
        print("\n[DRY RUN] Nothing was written.  Re-run without --dry-run to proceed.")
        return

    # ---- Verify before deleting --------------------------------------------
    ok = verify(datasets)

    if not ok:
        print(
            "\n[ERROR] Verification found empty directories. "
            "Old directories were NOT deleted.\n"
            "Please inspect the output above and re-run.",
            file=sys.stderr,
        )
        sys.exit(1)

    # ---- Cleanup -----------------------------------------------------------
    if args.skip_cleanup:
        print("\n[INFO] --skip-cleanup set: original directories kept.")
        print("       Delete them manually when you are satisfied with the result.")
    else:
        print("\nAll checks passed.  Deleting original directories …")
        cleanup(datasets)
        print("Done.")


if __name__ == "__main__":
    main()