"""
heatmap_all_layers.py — Generate delta-similarity heatmaps for ALL layers.

Reads pre-computed delta_similarity_{scale}_L{layer}_{tag}.csv files and
generates heatmap plots for every layer.

Before running, verifies that the NPZ file contains all expected layers.
If the NPZ is missing layers, the script warns and exits (no partial output).

Output structure:
  results/{model}/plots/all/heatmap/heatmap_{scale}_L{layer}_all_pairs.png
  results/{model}/plots/all/heatmap/heatmap_{scale}_L{layer}_both_correct.png

Usage:
    python heatmap_all_layers.py --model qwen_super --scale qwen3_235b
    python heatmap_all_layers.py --model qwen_super --scale qwen3_235b --overwrite
    python heatmap_all_layers.py                     # all models, all scales
"""

import argparse
import glob
import os
import re

import matplotlib
matplotlib.use('Agg')
import numpy as np
import pandas as pd

# Import plot function and color constants from the main pipeline
import sys
_HERE = os.path.dirname(os.path.abspath(__file__))
if _HERE not in sys.path:
    sys.path.insert(0, _HERE)

from swap_analysis import plot_delta_heatmap, CATEGORY_ORDER

RESULTS_DIR = os.path.join(_HERE, 'results')
TAGS = ['all_pairs', 'both_correct']


# ---------------------------------------------------------------------------
# NPZ completeness check
# ---------------------------------------------------------------------------

def check_npz_layers(npz_path: str):
    """Return sorted list of layer indices present in the NPZ (via orig_L* keys).
    Returns an empty list if the file doesn't exist or has no orig_L* keys.
    """
    if not os.path.exists(npz_path):
        return []
    data = np.load(npz_path, allow_pickle=True)
    layer_keys = [k for k in data.files if k.startswith('orig_L')]
    data.close()
    return sorted(int(k.replace('orig_L', '')) for k in layer_keys)


def check_csv_layers(csv_dir: str, scale: str, tag: str):
    """Return sorted list of layer indices that have a delta_similarity CSV."""
    pattern = os.path.join(csv_dir, f'delta_similarity_{scale}_L*_{tag}.csv')
    files = glob.glob(pattern)
    layers = []
    for fpath in files:
        m = re.search(rf'delta_similarity_{re.escape(scale)}_L(\d+)_{re.escape(tag)}\.csv$',
                      os.path.basename(fpath))
        if m:
            layers.append(int(m.group(1)))
    return sorted(layers)


# ---------------------------------------------------------------------------
# Per-model/scale processing
# ---------------------------------------------------------------------------

def process(model: str, scale: str, model_dir: str, overwrite: bool) -> int:
    npz_path = os.path.join(model_dir, 'npz', f'vectors_{scale}.npz')
    csv_dir  = os.path.join(model_dir, 'csv')
    out_dir  = os.path.join(model_dir, 'plots', 'all', 'heatmap')

    # ── 1. Check NPZ completeness ────────────────────────────────────────────
    npz_layers = check_npz_layers(npz_path)
    if not npz_layers:
        print(f'  [{model}/{scale}] NPZ not found or empty: {npz_path}')
        return 0

    # Cross-check: CSVs should cover the same layers for all_pairs
    csv_layers = check_csv_layers(csv_dir, scale, 'all_pairs')
    missing = set(npz_layers) - set(csv_layers)
    if missing:
        print(f'  [{model}/{scale}] WARNING: {len(missing)} NPZ layers have no CSV '
              f'(e.g. L{sorted(missing)[:5]}). '
              f'Re-run inference to regenerate missing CSVs. Skipping.')
        return 0

    print(f'  [{model}/{scale}] {len(npz_layers)} layers (L{npz_layers[0]}–L{npz_layers[-1]})')
    os.makedirs(out_dir, exist_ok=True)

    # ── 2. Generate plots ────────────────────────────────────────────────────
    # Load category validity if available (for unreliable cat markers)
    cat_validity = {}
    cv_path = os.path.join(model_dir, 'json', f'category_validity_{scale}.json')
    if os.path.exists(cv_path):
        import json
        with open(cv_path) as f:
            cat_validity = json.load(f)
    unreliable = [c for c, v in cat_validity.items() if not v.get('reliable', True)]

    saved = 0
    for i, layer in enumerate(npz_layers):
        print(f'  L{layer:>3} ({i+1}/{len(npz_layers)})', end='\r', flush=True)

        for tag in TAGS:
            out_path = os.path.join(out_dir, f'heatmap_{scale}_L{layer}_{tag}.png')
            if not overwrite and os.path.exists(out_path):
                continue

            csv_path = os.path.join(csv_dir, f'delta_similarity_{scale}_L{layer}_{tag}.csv')
            if not os.path.exists(csv_path):
                continue  # both_correct CSV may not exist for all layers

            df = pd.read_csv(csv_path, index_col=0)
            # Ensure canonical category order (drop missing, keep order)
            available = [c for c in CATEGORY_ORDER if c in df.index]
            if not available:
                continue
            df = df.loc[available, available]

            title = (f'{model.upper()} ({scale}) — Delta Heatmap L{layer} '
                     f'({"both-correct" if tag == "both_correct" else "all pairs"})')
            cond_unreliable = unreliable if tag == 'all_pairs' else []
            plot_delta_heatmap(df, title, out_path, unreliable_cats=cond_unreliable)
            saved += 1

    print()  # newline after progress
    return saved


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

def main():
    parser = argparse.ArgumentParser(
        description='Generate delta-similarity heatmaps for all layers from pre-computed CSVs')
    parser.add_argument('--model', help='Restrict to one model directory (e.g. qwen_super)')
    parser.add_argument('--scale', help='Restrict to one scale (e.g. qwen3_235b)')
    parser.add_argument('--overwrite', action='store_true',
                        help='Regenerate plots even if they already exist')
    parser.add_argument('--results-dir', default=RESULTS_DIR,
                        help='Path to results/ directory')
    args = parser.parse_args()

    results_dir = args.results_dir
    if not os.path.isdir(results_dir):
        print(f'Results directory not found: {results_dir}')
        return

    model_dirs = sorted(
        m for m in os.listdir(results_dir)
        if os.path.isdir(os.path.join(results_dir, m))
    )
    if args.model:
        model_dirs = [m for m in model_dirs if m == args.model]
        if not model_dirs:
            print(f"Model '{args.model}' not found in {results_dir}")
            return

    total_saved = 0
    for model in model_dirs:
        model_dir = os.path.join(results_dir, model)
        npz_dir   = os.path.join(model_dir, 'npz')
        if not os.path.isdir(npz_dir):
            continue

        npz_files = sorted(
            f for f in os.listdir(npz_dir)
            if f.startswith('vectors_') and f.endswith('.npz')
        )
        if args.scale:
            npz_files = [f for f in npz_files
                         if re.match(rf'vectors_{re.escape(args.scale)}\.npz$', f)]
        if not npz_files:
            print(f'[{model}] no matching NPZ files, skipping')
            continue

        for npz_file in npz_files:
            m = re.match(r'vectors_(.+)\.npz$', npz_file)
            if not m:
                continue
            scale = m.group(1)
            n = process(model, scale, model_dir, args.overwrite)
            total_saved += n

    print(f'\nDone. Saved {total_saved} heatmap plots.')


if __name__ == '__main__':
    main()