"""Phase 3: Build final clean dataset with proper splits, labels, and features."""

import pandas as pd
import numpy as np
from pathlib import Path
import json
from sklearn.model_selection import train_test_split
import warnings

warnings.filterwarnings('ignore')

ROOT = Path("/Users/manhnguyen/Project/NOC_DNA_V2")
RECONSTRUCTED_DIR = ROOT / "data/reconstructed"
RAW_DATA_DIR = ROOT / "data/PROVEDIt_1-5-Person CSVs UnFiltered"
OUTPUT_DIR_RD14 = ROOT / "data/reconstructed/rd14_clean"
OUTPUT_DIR_RD12 = ROOT / "data/reconstructed/rd12_clean"

OUTPUT_DIR_RD14.mkdir(parents=True, exist_ok=True)
OUTPUT_DIR_RD12.mkdir(parents=True, exist_ok=True)

def load_sample_labels():
    """Load sample labels from Phase 2."""
    print("📖 Loading sample labels from Phase 2...")
    labels_df = pd.read_csv(RECONSTRUCTED_DIR / "sample_labels.csv")
    print(f"✅ Loaded {len(labels_df)} samples")
    return labels_df

def filter_high_quality_samples(labels_df):
    """Filter for high-quality samples based on criteria."""
    print("\n🔍 Filtering for high-quality samples...")

    print(f"   Starting with: {len(labels_df)} samples")

    # Filter 1: Must have at least 20 markers
    filtered = labels_df[labels_df['num_markers'] >= 20].copy()
    print(f"   After marker count filter: {len(filtered)} samples")

    # Filter 2: Only keep 1-5 person samples (should all be)
    filtered = filtered[filtered['num_contributors'].isin([1, 2, 3, 4, 5])].copy()
    print(f"   After contributor count filter: {len(filtered)} samples")

    # Filter 3: Only keep known studies
    filtered = filtered[filtered['study_id'].isin(['RD14-0003', 'RD12-0002'])].copy()
    print(f"   After study filter: {len(filtered)} samples")

    # Filter 4: Only keep known kits
    known_kits = ['IDPlus28', 'F6C29', 'GF29', 'IDPlus29', 'PP16HS32']
    filtered = filtered[filtered['kit'].isin(known_kits)].copy()
    print(f"   After kit filter: {len(filtered)} samples")

    print(f"\n   ✅ Final filtered count: {len(filtered)} samples")
    return filtered

def balance_classes(labels_df):
    """Balance unknown_present classes (0 vs 1)."""
    print("\n⚖️  Balancing class distribution...")

    # Separate by class
    no_unknown = labels_df[labels_df['unknown_present'] == 0]
    has_unknown = labels_df[labels_df['unknown_present'] == 1]

    print(f"   No unknown (0): {len(no_unknown)}")
    print(f"   Has unknown (1): {len(has_unknown)}")

    # Balance by downsampling the larger class
    min_class_size = min(len(no_unknown), len(has_unknown))

    no_unknown_balanced = no_unknown.sample(n=min_class_size, random_state=42)
    has_unknown_balanced = has_unknown.sample(n=min_class_size, random_state=42)

    balanced = pd.concat([no_unknown_balanced, has_unknown_balanced], ignore_index=True)
    balanced = balanced.sample(frac=1, random_state=42).reset_index(drop=True)

    print(f"   ✅ Balanced dataset: {len(balanced)} samples ({len(no_unknown_balanced)} per class)")
    return balanced

def create_splits(labels_df):
    """Create train/dev/test splits stratified by unknown_present."""
    print("\n📊 Creating train/dev/test splits...")

    # 60/20/20 split
    train, temp = train_test_split(
        labels_df, test_size=0.4, random_state=42, stratify=labels_df['unknown_present']
    )

    dev, test = train_test_split(
        temp, test_size=0.5, random_state=42, stratify=temp['unknown_present']
    )

    # Add partition column
    train['partition'] = 'train'
    dev['partition'] = 'dev'
    test['partition'] = 'test'

    # Add split_id for multi-split format
    combined = pd.concat([train, dev, test], ignore_index=True)
    combined['split_id'] = 'split_01'  # Can extend to multiple splits later
    combined['benchmark_id'] = combined['study_id'].apply(
        lambda x: 'rd14-fullref-50_multisplit_v2' if x == 'RD14-0003' else 'rd12-fullref-61_multisplit_v2'
    )

    print(f"   Train: {len(train)} samples")
    print(f"   Dev: {len(dev)} samples")
    print(f"   Test: {len(test)} samples")

    return combined

def extract_peak_features(sample_file, raw_data_dir):
    """Extract peak features from raw CSV for a sample."""
    features = {}

    try:
        # Find the CSV file in raw data
        found_files = list(raw_data_dir.rglob(f"{sample_file}"))
        if not found_files:
            return features

        csv_path = found_files[0]
        df = pd.read_csv(csv_path)

        # Extract peak statistics by marker
        for _, row in df.iterrows():
            marker = row['Marker']

            # Count non-empty peaks
            peaks = 0
            max_height = 0
            sum_height = 0

            for i in range(1, 101):
                height_col = f'Height {i}'
                if height_col in df.columns:
                    height = row[height_col]
                    if pd.notna(height) and height != '' and height != 'nan':
                        try:
                            h = float(height)
                            if h > 0:
                                peaks += 1
                                max_height = max(max_height, h)
                                sum_height += h
                        except:
                            pass

            if peaks > 0:
                features[f"{marker}_peak_count"] = peaks
                features[f"{marker}_max_height"] = max_height
                features[f"{marker}_sum_height"] = sum_height

    except Exception as e:
        pass

    return features

def extract_marker_features(sample_genotype):
    """Extract marker-based features."""
    features = {}

    if not sample_genotype:
        return features

    # Count markers
    features['num_markers'] = len(sample_genotype)

    # Allele distribution
    num_homozygous = sum(1 for alleles in sample_genotype.values() if len(set(alleles.split(','))) == 1)
    features['num_homozygous'] = num_homozygous
    features['num_heterozygous'] = len(sample_genotype) - num_homozygous

    return features

def build_feature_matrix(labels_df):
    """Build complete feature matrix with peak and marker features."""
    print("\n🛠️  Building feature matrix...")

    features_list = []

    for idx, row in labels_df.iterrows():
        if idx % 100 == 0:
            print(f"   Processing {idx}/{len(labels_df)}...", end='\r')

        sample_file = row['sample_file']
        feature_dict = {
            'sample_file': sample_file,
            'study_id': row['study_id'],
            'kit': row['kit'],
            'num_contributors': row['num_contributors'],
            'num_known': row['num_known'],
            'num_unknown': row['num_unknown'],
            'unknown_present': row['unknown_present'],
            'num_markers_detected': row['num_markers'],
            'partition': row['partition'],
            'split_id': row['split_id'],
            'benchmark_id': row['benchmark_id']
        }

        # Try to add peak features
        peak_features = extract_peak_features(sample_file, RAW_DATA_DIR)
        feature_dict.update(peak_features)

        features_list.append(feature_dict)

    feature_df = pd.DataFrame(features_list)
    print(f"✅ Created feature matrix: {len(feature_df)} samples × {len(feature_df.columns)} features")
    return feature_df

def save_dataset(feature_df):
    """Save dataset split by study."""
    print("\n💾 Saving datasets...")

    # Split by study
    rd14_df = feature_df[feature_df['study_id'] == 'RD14-0003'].copy()
    rd12_df = feature_df[feature_df['study_id'] == 'RD12-0002'].copy()

    # Save RD14
    rd14_labels = rd14_df[['sample_file', 'benchmark_id', 'split_id', 'partition', 'study_id', 'kit',
                          'num_known', 'num_unknown', 'unknown_present', 'num_contributors']].copy()
    rd14_labels.to_csv(OUTPUT_DIR_RD14 / "sample_labels_all_splits.csv", index=False)

    # Save RD12
    rd12_labels = rd12_df[['sample_file', 'benchmark_id', 'split_id', 'partition', 'study_id', 'kit',
                          'num_known', 'num_unknown', 'unknown_present', 'num_contributors']].copy()
    rd12_labels.to_csv(OUTPUT_DIR_RD12 / "sample_labels_all_splits.csv", index=False)

    print(f"   ✅ RD14 dataset: {len(rd14_df)} samples")
    print(f"      File: {OUTPUT_DIR_RD14}/sample_labels_all_splits.csv")
    print(f"   ✅ RD12 dataset: {len(rd12_df)} samples")
    print(f"      File: {OUTPUT_DIR_RD12}/sample_labels_all_splits.csv")

    # Save full feature matrices
    rd14_df.to_csv(OUTPUT_DIR_RD14 / "features_matrix.csv", index=False)
    rd12_df.to_csv(OUTPUT_DIR_RD12 / "features_matrix.csv", index=False)

    # Create summary
    summary = {
        "rd14": {
            "total_samples": len(rd14_df),
            "train": len(rd14_df[rd14_df['partition'] == 'train']),
            "dev": len(rd14_df[rd14_df['partition'] == 'dev']),
            "test": len(rd14_df[rd14_df['partition'] == 'test']),
            "unknown_0": len(rd14_df[rd14_df['unknown_present'] == 0]),
            "unknown_1": len(rd14_df[rd14_df['unknown_present'] == 1]),
            "num_features": len(rd14_df.columns)
        },
        "rd12": {
            "total_samples": len(rd12_df),
            "train": len(rd12_df[rd12_df['partition'] == 'train']),
            "dev": len(rd12_df[rd12_df['partition'] == 'dev']),
            "test": len(rd12_df[rd12_df['partition'] == 'test']),
            "unknown_0": len(rd12_df[rd12_df['unknown_present'] == 0]),
            "unknown_1": len(rd12_df[rd12_df['unknown_present'] == 1]),
            "num_features": len(rd12_df.columns)
        }
    }

    with open(OUTPUT_DIR_RD14 / "dataset_summary.json", "w") as f:
        json.dump(summary, f, indent=2)

    with open(OUTPUT_DIR_RD12 / "dataset_summary.json", "w") as f:
        json.dump(summary, f, indent=2)

    print(f"\n📊 Dataset Summary:")
    print(json.dumps(summary, indent=2))

    return rd14_df, rd12_df

def main():
    print("=" * 80)
    print("🔧 PHASE 3: Build Final Clean Dataset with Proper Splits")
    print("=" * 80)

    # Load sample labels from Phase 2
    labels_df = load_sample_labels()

    # Filter for high quality
    filtered_df = filter_high_quality_samples(labels_df)

    # Balance classes
    balanced_df = balance_classes(filtered_df)

    # Create splits
    split_df = create_splits(balanced_df)

    # Build feature matrix
    feature_df = build_feature_matrix(split_df)

    # Save datasets
    rd14_df, rd12_df = save_dataset(feature_df)

    print("\n" + "=" * 80)
    print("✅ PHASE 3 COMPLETE!")
    print("=" * 80)
    print(f"\nDatasets ready for training:")
    print(f"  RD14: {OUTPUT_DIR_RD14}/sample_labels_all_splits.csv")
    print(f"  RD12: {OUTPUT_DIR_RD12}/sample_labels_all_splits.csv")
    print(f"\nNext step: Phase 4 - Retrain models with new data")

if __name__ == "__main__":
    main()