#!/usr/bin/env python3
"""
HF Spaces Document Processing Pipeline
Processes synthetic_policies documents and stores embeddings in HF Dataset
"""

import hashlib
import logging
from pathlib import Path

from src.embedding.hf_embedding_service import HFEmbeddingService

# Import your existing services
from src.ingestion.document_chunker import DocumentChunker
from src.ingestion.document_parser import DocumentParser
from src.vector_store.hf_dataset_store import HFDatasetVectorStore


class HFDocumentPipeline:
    """
    Free-tier document processing pipeline for HF Spaces
    """

    def __init__(self):
        self.document_parser = DocumentParser()
        self.document_chunker = DocumentChunker(chunk_size=500, overlap=50)
        self.embedding_service = HFEmbeddingService()
        self.vector_store = HFDatasetVectorStore()

    def process_synthetic_policies(self, policies_dir: str = "synthetic_policies"):
        """
        Process all policy documents and store embeddings
        """
        logging.info("🚀 Starting synthetic policies processing...")

        policy_files = list(Path(policies_dir).glob("*.txt"))
        if not policy_files:
            policy_files = list(Path(policies_dir).glob("*.md"))

        if not policy_files:
            logging.warning(f"⚠️  No policy files found in {policies_dir}")
            return

        logging.info(f"📁 Found {len(policy_files)} policy files to process")

        all_documents = []
        all_embeddings = []
        all_metadata = []

        for idx, policy_file in enumerate(policy_files, 1):
            try:
                logging.info(f"📄 Processing file {idx}/{len(policy_files)}: {policy_file.name}")

                # Read document
                with open(policy_file, "r", encoding="utf-8") as f:
                    content = f.read()

                logging.info(f"📏 Document length: {len(content)} characters")

                # Parse document to get structured data (parser validates/throws on errors)
                _ = self.document_parser.parse_document(str(policy_file))

                # Chunk the document using the proper chunker
                chunks = self.document_chunker.chunk_document(
                    text=content,
                    doc_metadata={
                        "filename": policy_file.name,
                        "source": str(policy_file),
                    },
                )

                logging.info(f"✂️  Created {len(chunks)} chunks from {policy_file.name}")

                # Process in batches to stay within memory limits
                batch_size = 10  # Small batches for free tier
                total_batches = (len(chunks) + batch_size - 1) // batch_size

                for batch_idx in range(0, len(chunks), batch_size):
                    batch_num = (batch_idx // batch_size) + 1
                    batch_chunks = chunks[batch_idx : batch_idx + batch_size]
                    batch_texts = [chunk["content"] for chunk in batch_chunks]

                    logging.info(f"🔄 Processing batch {batch_num}/{total_batches} ({len(batch_texts)} chunks)")

                    # Generate embeddings using HF API
                    try:
                        batch_embeddings = self.embedding_service.get_embeddings(batch_texts)
                        logging.info(f"✅ Generated {len(batch_embeddings) if batch_embeddings else 0} embeddings")
                    except Exception as e:
                        logging.error(f"❌ Embedding generation failed for batch {batch_num}: {e}")
                        continue

                    if batch_embeddings:
                        all_documents.extend(batch_texts)
                        all_embeddings.extend(batch_embeddings)

                        # Create metadata from chunk metadata
                        for chunk in batch_chunks:
                            metadata = {
                                "source_file": policy_file.name,
                                "chunk_id": chunk["metadata"].get("chunk_id", ""),
                                "chunk_index": chunk["metadata"].get("chunk_index", 0),
                                "content_hash": hashlib.md5(chunk["content"].encode()).hexdigest(),
                            }
                            all_metadata.append(metadata)

                logging.info(f"✅ Completed {policy_file.name}: {len(chunks)} chunks processed")

            except Exception as e:
                logging.error(f"❌ Error processing {policy_file}: {e}")

        # Save all embeddings to HF Dataset
        if all_embeddings:
            logging.info(f"💾 Saving {len(all_embeddings)} total embeddings to HF Dataset...")
            try:
                self.vector_store.save_embeddings(all_documents, all_embeddings, all_metadata)
                logging.info(f"🎉 Pipeline complete: {len(all_embeddings)} total embeddings saved successfully!")
            except Exception as e:
                logging.error(f"❌ Failed to save embeddings: {e}")
        else:
            logging.warning("⚠️  No embeddings generated - pipeline completed with no results!")


def main():
    """Run the document processing pipeline"""
    pipeline = HFDocumentPipeline()
    pipeline.process_synthetic_policies()


def run_hf_pipeline():
    """Entry point for HF document processing pipeline - called from app startup"""
    try:
        logging.info("Starting HF document processing pipeline from app startup...")
        pipeline = HFDocumentPipeline()
        pipeline.process_synthetic_policies()
        logging.info("HF pipeline completed successfully")
        return True
    except Exception as e:
        logging.error(f"HF pipeline failed: {e}")
        return False


if __name__ == "__main__":
    logging.basicConfig(level=logging.INFO)
    main()