# knowledge/models.py — Core data structures for knowledge management
import hashlib
from pydantic import BaseModel, Field


class DocumentMetadata(BaseModel):
    doc_id: str
    filename: str
    path: str
    title: str = "Untitled Document"
    section: str = ""
    subsection: str = ""
    language: str = "ar"
    source_type: str = "markdown"


class Document(BaseModel):
    metadata: DocumentMetadata
    content: str


class Chunk(BaseModel):
    chunk_id: str
    doc_id: str
    filename: str
    path: str
    title: str
    section: str = ""
    subsection: str = ""
    text: str
    language: str = "ar"
    source_type: str = "markdown"
    token_count: int = 0
    heading_context: str = ""
    chunk_index: int = 0

    def formatted_for_context(self) -> str:
        """Format chunk with source metadata for LLM context payload."""
        header_parts = []
        if self.filename:
            header_parts.append(f"المستند: {self.filename}")
        if self.title and self.title != self.filename:
            header_parts.append(f"العنوان: {self.title}")
        if self.section:
            header_parts.append(f"القسم: {self.section}")
        if self.subsection:
            header_parts.append(f"الفرع: {self.subsection}")
        
        meta_header = " | ".join(header_parts)
        return f"--- [{meta_header}] ---\n{self.text.strip()}\n"