# core/bulk_importer.py
import re
from database.connection import get_connection

class BulkImporter:
    def __init__(self):
        # Matches typical patterns: "Spanish word", "English translation", "Unit metadata"
        self.row_regex = re.compile(r'"([^"]+)"\s*,\s*"([^"]+)"\s*,\s*"([^"]+)"')

    def clean_text(self, text: str) -> str:
        """Strips newlines and extra spaces from extracted data fields."""
        return text.replace('\n', ' ').strip()

    def parse_unit(self, context_str: str) -> int:
        """
        Extracts the unit integer from codes like 'U5_3D', 'U7 4A', or 'UG_11B'.
        Returns None if it's a general marker like 'UT LEX'.
        """
        match = re.search(r'U([0-9])', context_str)
        if match:
            return int(match.group(1))
        return None

    def import_glossary_file(self, file_path: str, textbook_name: str):
        """Reads the structural text lines and inserts them into the translation database."""
        conn = get_connection()
        cursor = conn.cursor()
        
        print(f"📖 Starting bulk ingestion for '{file_path}'...")
        count = 0
        
        try:
            with open(file_path, 'r', encoding='utf-8') as f:
                content = f.read()
            
            # Find all matching row structures inside the text
            matches = self.row_regex.findall(content)
            
            for es_raw, en_raw, ctx_raw in matches:
                spanish_text = self.clean_text(es_raw)
                english_text = self.clean_text(en_raw)
                context_tag = self.clean_text(ctx_raw)
                unit_number = self.parse_unit(context_tag)
                
                # Skip header rows or structural markers
                if spanish_text.lower() in ["alphabetical glossary", "spanish", "word"]:
                    continue

                # 1. Insert Spanish Term
                cursor.execute("""
                    INSERT INTO phrases (text, language, textbook, unit, source_context)
                    VALUES (?, 'es', ?, ?, ?)
                """, (spanish_text, textbook_name, unit_number, context_tag))
                es_id = cursor.lastrowid

                # 2. Insert English Term
                cursor.execute("""
                    INSERT INTO phrases (text, language, textbook, unit, source_context)
                    VALUES (?, 'en', ?, ?, ?)
                """, (english_text, textbook_name, unit_number, context_tag))
                en_id = cursor.lastrowid

                # 3. Create Bidirectional Bridges
                cursor.execute("INSERT INTO translations (source_phrase_id, target_phrase_id) VALUES (?, ?)", (es_id, en_id))
                cursor.execute("INSERT INTO translations (source_phrase_id, target_phrase_id) VALUES (?, ?)", (en_id, es_id))
                
                count += 1

            conn.commit()
            print(f"🎉 Successfully imported {count} linked glossary pairs into SQLite!")
            return count

        except Exception as e:
            conn.rollback()
            print(f"❌ Error during bulk data ingestion: {e}")
            return 0
        finally:
            conn.close()