import click
import os
import glob
import time

from sqlalchemy import create_engine
from sqlalchemy.orm import sessionmaker
from sqlalchemy.ext.declarative import declarative_base

from flask_sqlalchemy import SQLAlchemy

from app.settings import app_cfg

@click.command('migrate_to_mysql')
@click.pass_context
def cli(ctx):
  """
  - Create connections to both databases
  - For each table, for each row, insert from one to the other
  """
  mysql_session, mysql_base = make_mysql_base()
  sqlite_session, sqlite_base = make_sqlite3_base()
  mysql_classes = make_classes(mysql_base)
  sqlite_classes = make_classes(sqlite_base)

  for mysql_class, sqlite_class in zip(mysql_classes, sqlite_classes):
    sqlite_objs = sqlite_session.query(sqlite_class).order_by(sqlite_class.id).all()
    for sqlite_obj in sqlite_objs:
      mysql_obj = mysql_class()
      for column in sqlite_class.__table__.columns:
        table_name, column_name = str(column).split(".")
        # print(f"{table_name} => {column_name}")
        # if column_name != 'id':
        setattr(mysql_obj, column_name, getattr(sqlite_obj, column_name))
      mysql_session.add(mysql_obj)
      mysql_session.commit()

def make_mysql_base():
  """Make a Mysql connection"""
  connection_url = "mysql+pymysql://{}:{}@{}/{}?charset=utf8mb4".format(
    os.getenv("DB_USER"),
    os.getenv("DB_PASS"),
    os.getenv("DB_HOST"),
    os.getenv("DB_NAME")
  )
  return make_base(connection_url)

def make_sqlite3_base():
  """Make a SQLite3 connection"""
  connection_url = "sqlite:///{}".format(os.path.join(app_cfg.DIR_DATABASE, 'animism.sqlite3'))
  return make_base(connection_url)

def make_base(connection_url):
  """Make a connection base from a connection URL"""
  engine = create_engine(connection_url, encoding="utf-8", pool_recycle=3600)
  Session = sessionmaker(bind=engine)
  Base = declarative_base()
  Base.metadata.bind = engine
  db = SQLAlchemy()
  return Session(), Base

def make_classes(Base):
  """Make classes from a base"""

  from sqlalchemy import create_engine, Table, Column, Text, String, Integer, \
    Boolean, Float, DateTime, JSON, ForeignKey
  from sqlalchemy_utc import UtcDateTime, utcnow

  class Upload(Base):
    """Table for storing references to various media"""
    __tablename__ = 'upload'
    id = Column(Integer, primary_key=True)
    graph_id = Column(Integer, ForeignKey('graph.id'), nullable=True)
    sha256 = Column(String(256), nullable=False)
    fn = Column(String(256), nullable=False)
    ext = Column(String(4, convert_unicode=True), nullable=False)
    tag = Column(String(64, convert_unicode=True), nullable=True)
    username = Column(String(16, convert_unicode=True), nullable=False)
    created_at = Column(UtcDateTime(), default=utcnow())

  class Tile(Base):
    """Table for storing references to tiles"""
    __tablename__ = 'tile'
    id = Column(Integer, primary_key=True)
    graph_id = Column(Integer, ForeignKey('graph.id'), nullable=True)
    page_id = Column(Integer, ForeignKey('page.id'), nullable=True)
    target_page_id = Column(Integer, ForeignKey('page.id'), nullable=True)
    type = Column(String(16, convert_unicode=True), nullable=False)
    sort_order = Column(Integer, default=0)
    settings = Column(JSON, default={}, nullable=True)
    created_at = Column(UtcDateTime(), default=utcnow())
    updated_at = Column(UtcDateTime(), onupdate=utcnow())

  class Page(Base):
    """Table for storing references to pages"""
    __tablename__ = 'page'
    id = Column(Integer, primary_key=True)
    graph_id = Column(Integer, ForeignKey('graph.id'), nullable=True)
    path = Column(String(64, convert_unicode=True), nullable=False)
    title = Column(String(64, convert_unicode=True), nullable=False)
    username = Column(String(32, convert_unicode=True), nullable=False)
    description = Column(Text(convert_unicode=True), nullable=False)
    settings = Column(JSON, default={}, nullable=True)
    created_at = Column(UtcDateTime(), default=utcnow())
    updated_at = Column(UtcDateTime(), onupdate=utcnow())

  class Graph(Base):
    """Table for storing references to graphs"""
    __tablename__ = 'graph'
    id = Column(Integer, primary_key=True)
    home_page_id = Column(Integer, nullable=True)
    path = Column(String(64, convert_unicode=True), nullable=False)
    title = Column(String(64, convert_unicode=True), nullable=False)
    username = Column(String(32, convert_unicode=True), nullable=False)
    description = Column(Text(convert_unicode=True), nullable=False)
    settings = Column(JSON, default={}, nullable=True)
    created_at = Column(UtcDateTime(), default=utcnow())
    updated_at = Column(UtcDateTime(), onupdate=utcnow())

  return [ Upload, Graph, Page, Tile ]