"""Report metadata management."""

from typing import Dict, List, Any, Set
from pathlib import Path


def get_report_metadata(chunks: List[Dict[str, Any]]) -> Dict[str, Any]:
    """
    Extract metadata from chunks.
    
    Args:
        chunks: List of chunk dictionaries
        
    Returns:
        Dictionary with report metadata
    """
    if not chunks:
        return {}
    
    sources = set()
    filenames = set()
    years = set()
    
    for chunk in chunks:
        metadata = chunk.get("metadata", {})
        
        if "source" in metadata:
            sources.add(metadata["source"])
        
        if "filename" in metadata:
            filenames.add(metadata["filename"])
        
        if "year" in metadata:
            years.add(metadata["year"])
    
    return {
        "sources": sorted(list(sources)),
        "filenames": sorted(list(filenames)),
        "years": sorted(list(years)),
        "total_chunks": len(chunks)
    }


def get_available_sources() -> List[str]:
    """
    Get list of available report sources (legacy compatibility).
    
    Returns:
        List of source categories
    """
    # This would typically come from the original auditqa_old.reports module
    # For now, return common categories
    return [
        "Consolidated",
        "Ministry, Department, Agency and Projects", 
        "Local Government",
        "Value for Money",
        "Thematic",
        "Hospital",
        "Project"
    ]


def get_source_subtypes() -> Dict[str, List[str]]:
    """
    Get mapping of sources to their subtypes (placeholder).
    
    Returns:
        Dictionary mapping sources to subtypes
    """
    # This was originally imported from auditqa_old.reports.new_files
    # For now, return a placeholder structure
    return {
        "Consolidated": ["Annual Consolidated OAG 2024", "Annual Consolidated OAG 2023"],
        "Local Government": ["District Reports", "Municipal Reports"],
        "Ministry, Department, Agency and Projects": ["Ministry Reports", "Agency Reports"],
        "Value for Money": ["VFM Reports 2024", "VFM Reports 2023"],
        "Thematic": ["Thematic Reports 2024", "Thematic Reports 2023"],
        "Hospital": ["Hospital Reports 2024", "Hospital Reports 2023"],
        "Project": ["Project Reports 2024", "Project Reports 2023"]
    }


def validate_report_filters(
    reports: List[str] = None,
    sources: str = None,
    subtype: List[str] = None,
    available_metadata: Dict[str, Any] = None
) -> Dict[str, Any]:
    """
    Validate report filter parameters.
    
    Args:
        reports: List of specific report filenames
        sources: Source category
        subtype: List of subtypes
        available_metadata: Available metadata for validation
        
    Returns:
        Dictionary with validation results
    """
    validation_result = {
        "valid": True,
        "warnings": [],
        "errors": []
    }
    
    if not available_metadata:
        validation_result["warnings"].append("No metadata available for validation")
        return validation_result
    
    available_sources = available_metadata.get("sources", [])
    available_filenames = available_metadata.get("filenames", [])
    
    # Validate sources
    if sources and sources not in available_sources:
        validation_result["errors"].append(f"Source '{sources}' not found in available sources")
        validation_result["valid"] = False
    
    # Validate reports
    if reports:
        for report in reports:
            if report not in available_filenames:
                validation_result["warnings"].append(f"Report '{report}' not found in available reports")
    
    # Validate subtypes
    if subtype:
        for sub in subtype:
            if sub not in available_filenames:
                validation_result["warnings"].append(f"Subtype '{sub}' not found in available reports")
    
    return validation_result


def get_report_statistics(chunks: List[Dict[str, Any]]) -> Dict[str, Any]:
    """
    Get statistics about reports in chunks.
    
    Args:
        chunks: List of chunk dictionaries
        
    Returns:
        Dictionary with report statistics
    """
    if not chunks:
        return {}
    
    stats = {
        "total_chunks": len(chunks),
        "sources": {},
        "years": {},
        "avg_chunk_length": 0,
        "total_content_length": 0
    }
    
    total_length = 0
    
    for chunk in chunks:
        content = chunk.get("content", "")
        total_length += len(content)
        
        metadata = chunk.get("metadata", {})
        
        # Count by source
        source = metadata.get("source", "Unknown")
        stats["sources"][source] = stats["sources"].get(source, 0) + 1
        
        # Count by year
        year = metadata.get("year", "Unknown")
        stats["years"][year] = stats["years"].get(year, 0) + 1
    
    stats["total_content_length"] = total_length
    stats["avg_chunk_length"] = total_length / len(chunks) if chunks else 0
    
    return stats


def filter_chunks_by_metadata(
    chunks: List[Dict[str, Any]],
    source_filter: str = None,
    filename_filter: List[str] = None,
    year_filter: List[str] = None
) -> List[Dict[str, Any]]:
    """
    Filter chunks by metadata criteria.
    
    Args:
        chunks: List of chunk dictionaries
        source_filter: Source to filter by
        filename_filter: List of filenames to filter by
        year_filter: List of years to filter by
        
    Returns:
        Filtered list of chunks
    """
    filtered_chunks = chunks
    
    if source_filter:
        filtered_chunks = [
            chunk for chunk in filtered_chunks
            if chunk.get("metadata", {}).get("source") == source_filter
        ]
    
    if filename_filter:
        filtered_chunks = [
            chunk for chunk in filtered_chunks
            if chunk.get("metadata", {}).get("filename") in filename_filter
        ]
    
    if year_filter:
        filtered_chunks = [
            chunk for chunk in filtered_chunks
            if chunk.get("metadata", {}).get("year") in year_filter
        ]
    
    return filtered_chunks