from flask import Flask, render_template, g
from flask.json import jsonify
from flask.templating import render_template_string
from sqlalchemy.orm import joinedload
import ttdb
from ttdb.model import HierarchyElement, obtain_session

#configuration
SQL_CONNECTION_STRING = "sqlite:///tt.db"
DEBUG = True

app = Flask(__name__)

#app.config.from_object('config')
app.config.from_object(__name__)

@app.before_request
def before_request():
    g.ttdb = obtain_session(app.config["SQL_CONNECTION_STRING"])

@app.teardown_request
def teardown_request(exception):
    #tdb = getattr(g, 'db', None)
    pass


@app.errorhandler(404)
def not_found(error):
    return render_template('404.html')

@app.route('/')
@app.route('/tree')
def tree():
    elements = g.ttdb.query(HierarchyElement).options(joinedload('children')).all()

    #root elements
    root_elements = [element for element in elements if element.parent_id is None]

    #render
    return render_template('tree.html', elements=root_elements)


@app.route('/get_children/<int:id>')
def get_children(id):
    element = g.ttdb.query(HierarchyElement).get(id)
    return jsonify(children=element.children)

@app.route('/table')
def table():
    #select all elements populating children right away
    elements = g.ttdb.query(HierarchyElement).options(joinedload('children', 'channel')).all()

    #root elements
    root_elements = [element for element in elements if element.parent_id is None]

    #recursive function to sort array according to hierarchy
    ordered_elements = []

    def build_hierarchy(el, level):
        ordered_elements.append(("&nbsp;"*5*level, el,))
        if len(el.children):
            for child in el.children:
                build_hierarchy(child, level+1)

    for root_element in root_elements:
        build_hierarchy(root_element, 0)

    #render
    return render_template('index.html', elements=ordered_elements)