"""Alembic migration environment configuration.

This module configures Alembic to work with the Flask application
and SQLAlchemy models.
"""

import os
from logging.config import fileConfig
from pathlib import Path

from alembic import context
from flask import Flask
from flask_sqlalchemy import SQLAlchemy

# this is the Alembic Config object, which provides
# access to the values within the .ini file in use.
config = context.config

# Interpret the config file for Python logging.
# This line sets up loggers basically.
if config.config_file_name is not None:
    fileConfig(config.config_file_name)

# Create minimal Flask app for migrations (without session initialization)
# This avoids Flask-Session trying to create tables before migrations run
app = Flask(__name__)
BASE_DIR = Path(__file__).parent.parent
DATA_DIR = BASE_DIR / "data"
DATA_DIR.mkdir(parents=True, exist_ok=True)

app.config["SQLALCHEMY_DATABASE_URI"] = os.environ.get(
    "DATABASE_URL", f"sqlite:///{DATA_DIR / 'sneaky-klaus.db'}"
)
app.config["SQLALCHEMY_TRACK_MODIFICATIONS"] = False

db = SQLAlchemy()
db.init_app(app)

# Import all models to register them with SQLAlchemy metadata
with app.app_context():
    from src.models import (  # noqa: F401
        Admin,
        Exchange,
        MagicToken,
        Participant,
        RateLimit,
    )

config.set_main_option("sqlalchemy.url", app.config["SQLALCHEMY_DATABASE_URI"])

# Add your model's MetaData object here for 'autogenerate' support
target_metadata = db.metadata


def run_migrations_offline() -> None:
    """Run migrations in 'offline' mode.

    This configures the context with just a URL
    and not an Engine, though an Engine is acceptable
    here as well.  By skipping the Engine creation
    we don't even need a DBAPI to be available.

    Calls to context.execute() here emit the given string to the
    script output.
    """
    url = config.get_main_option("sqlalchemy.url")
    context.configure(
        url=url,
        target_metadata=target_metadata,
        literal_binds=True,
        dialect_opts={"paramstyle": "named"},
    )

    with context.begin_transaction():
        context.run_migrations()


def run_migrations_online() -> None:
    """Run migrations in 'online' mode.

    In this scenario we need to create an Engine
    and associate a connection with the context.
    """

    # Use the Flask app's engine instead of creating a new one
    with app.app_context():
        connectable = db.engine

        with connectable.connect() as connection:
            context.configure(connection=connection, target_metadata=target_metadata)

            with context.begin_transaction():
                context.run_migrations()


if context.is_offline_mode():
    run_migrations_offline()
else:
    run_migrations_online()