#!/usr/bin/env python3
"""
Verify Critical Imports
========================
Checks that critical imports (re-exports) haven't been removed by linters.

This script verifies that essential import statements exist in key files,
preventing issues where tools like Ruff might remove imports that appear
unused but are actually critical for the application structure.
"""

import sys
from pathlib import Path

# Define critical imports that must exist
# Format: {file_path: [(import_line, description)]}
CRITICAL_IMPORTS: dict[str, list[tuple[str, str]]] = {
    "models/database/base.py": [
        ("from app.core.database import Base", "Re-export Base for all models"),
    ],
    "models/__init__.py": [
        ("from .database.base import Base", "Export Base for Alembic and models"),
    ],
    "models/database/__init__.py": [
        ("from .base import Base", "Export Base from database package"),
    ],
    "app/core/database.py": [
        (
            "from sqlalchemy.ext.declarative import declarative_base",
            "SQLAlchemy Base declaration",
        ),
        # Note: Might also use sqlalchemy.orm declarative_base in newer versions
    ],
}


class ImportVerifier:
    """Verifies critical imports exist in codebase"""

    def __init__(self, project_root: Path):
        self.project_root = project_root
        self.issues: list[str] = []

    def verify_all(self) -> bool:
        """Verify all critical imports"""
        print("🔍 Verifying critical imports...\n")

        all_good = True
        for file_path, imports in CRITICAL_IMPORTS.items():
            if not self.verify_file(file_path, imports):
                all_good = False

        return all_good

    def verify_file(
        self, file_path: str, required_imports: list[tuple[str, str]]
    ) -> bool:
        """Verify imports in a single file"""
        full_path = self.project_root / file_path

        if not full_path.exists():
            self.issues.append(f"❌ File not found: {file_path}")
            print(f"❌ {file_path}: File not found")
            return False

        content = full_path.read_text()
        file_ok = True

        for import_line, description in required_imports:
            # Check for exact import or variations
            if import_line in content:
                print(f"✅ {file_path}: {import_line}")
            else:
                # Check for alternative import formats
                alternatives = self._get_import_alternatives(import_line)
                found = any(alt in content for alt in alternatives)

                if found:
                    print(f"✅ {file_path}: {import_line} (alternative format)")
                else:
                    self.issues.append(
                        f"❌ {file_path}: Missing critical import\n"
                        f"   Expected: {import_line}\n"
                        f"   Purpose: {description}"
                    )
                    print(f"❌ {file_path}: Missing {import_line}")
                    file_ok = False

        print()
        return file_ok

    def _get_import_alternatives(self, import_line: str) -> list[str]:
        """Get alternative formats for an import"""
        alternatives = [import_line]

        # Handle 'from x import y' vs 'from x import (y)'
        if "from" in import_line and "import" in import_line:
            parts = import_line.split("import")
            if len(parts) == 2:
                from_part = parts[0].strip()
                import_part = parts[1].strip()

                # Add parenthesized version
                alternatives.append(f"{from_part} import ({import_part})")

                # Add version with 'as' clause
                alternatives.append(f"{import_line} as")

        # Handle declarative_base alternatives (sqlalchemy changes)
        if "declarative_base" in import_line:
            # Old style
            alternatives.append(
                "from sqlalchemy.ext.declarative import declarative_base"
            )
            # New style (SQLAlchemy 1.4+)
            alternatives.append("from sqlalchemy.orm import declarative_base")

        return alternatives

    def print_summary(self):
        """Print summary of verification"""
        print("\n" + "=" * 80)
        print("📊 CRITICAL IMPORTS VERIFICATION SUMMARY")
        print("=" * 80)

        if not self.issues:
            print("\n✅ All critical imports verified successfully!")
            print("\nAll re-export patterns are intact.")
        else:
            print(f"\n❌ Found {len(self.issues)} issue(s):\n")
            for issue in self.issues:
                print(issue)
                print()

            print("💡 RESOLUTION:")
            print("   1. Check if imports were removed by linter (Ruff)")
            print("   2. Add missing imports back to the files")
            print("   3. Update pyproject.toml to ignore F401 for these files")
            print("   4. Run this script again to verify")

        print("=" * 80)


def main():
    """Main entry point"""
    project_root = Path(__file__).parent.parent

    verifier = ImportVerifier(project_root)
    success = verifier.verify_all()
    verifier.print_summary()

    sys.exit(0 if success else 1)


if __name__ == "__main__":
    main()