import functools

from flask import (
    Blueprint, flash, g, redirect, render_template, request, session, url_for
)
from flask import Blueprint
from flask_restful import Resource, Api, reqparse

from .db import get_db

class Students(Resource):
    def get(self):
        db = get_db()
        cur = db.cursor()
        cur.execute("SELECT uid, last_name_val, first_name_val, middle_name_val, discipline_val, mark"
                    " FROM main"
                    " join last_name on main.last_name = last_name_id"
                    " join first_name on main.first_name = first_name_id"
                    " join middle_name on main.middle_name = middle_name_id"
                    " join discipline on main.discipline = discipline_id")
        students = cur.fetchall()
        def convert(data):
            return {
                'uid': data[0],
                'last_name': data[1],
                'first_name': data[2],
                'middle_name': data[3],
                'discipline': data[4],
                'mark': data[5]
            }
        students = [convert(student) for student in students]
        return students

    def post(self):
        db = get_db()
        cur = db.cursor()
        parser = reqparse.RequestParser()
        parser.add_argument('last_name')
        parser.add_argument('first_name')
        parser.add_argument('middle_name')
        parser.add_argument('discipline')
        parser.add_argument('mark')
        args = parser.parse_args()

        cur.execute("SELECT uid FROM main ORDER BY uid DESC LIMIT 1")
        uid = cur.fetchone()
        if uid is None:
            uid = 0
        else:
            uid = uid[0] + 1

        cur.execute("SELECT last_name_id FROM last_name WHERE last_name_val = %s", (args['last_name'],))
        last_name = cur.fetchone()
        if last_name is None:
            cur.execute("INSERT INTO last_name (last_name_val) VALUES (%s)", (args['last_name'],))
            cur.execute("SELECT last_name_id FROM last_name WHERE last_name_val = %s", (args['last_name'],))
            last_name = cur.fetchone()
            last_name = last_name[0]
        else:
            last_name = last_name[0]

        cur.execute("SELECT first_name_id FROM first_name WHERE first_name_val = %s", (args['first_name'],))
        first_name = cur.fetchone()
        if first_name is None:
            cur.execute("INSERT INTO first_name (first_name_val) VALUES (%s)", (args['first_name'],))
            cur.execute("SELECT first_name_id FROM first_name WHERE first_name_val = %s", (args['first_name'],))
            first_name = cur.fetchone()
            first_name = first_name[0]
        else:
            first_name = first_name[0]

        cur.execute("SELECT middle_name_id FROM middle_name WHERE middle_name_val = %s", (args['middle_name'],))
        middle_name = cur.fetchone()
        if middle_name is None:
            cur.execute("INSERT INTO middle_name (middle_name_val) VALUES (%s)", (args['middle_name'],))
            cur.execute("SELECT middle_name_id FROM middle_name WHERE middle_name_val = %s", (args['middle_name'],))
            middle_name = cur.fetchone()
            middle_name = middle_name[0]
        else:
            middle_name = middle_name[0]

        cur.execute("SELECT discipline_id FROM discipline WHERE discipline_val = %s", (args['discipline'],))
        discipline = cur.fetchone()
        if discipline is None:
            cur.execute("INSERT INTO discipline (discipline_val) VALUES (%s)", (args['discipline'],))
            cur.execute("SELECT discipline_id FROM discipline WHERE discipline_val = %s", (args['discipline'],))
            discipline = cur.fetchone()
            discipline = discipline[0]
        else:
            discipline = discipline[0]

        cur.execute("INSERT INTO main (uid, last_name, first_name, middle_name, discipline, mark)"
                    " VALUES (%s, %s, %s, %s, %s, %s)",
                    (uid, last_name, first_name, middle_name, discipline, args['mark']))

        db.commit()
        return {'uid': uid}, 201

class Student(Resource):
    def get(self, uid):
        db = get_db()
        cur = db.cursor()
        cur.execute("SELECT uid, last_name_val, first_name_val, middle_name_val, discipline_val, mark"
                    " FROM main"
                    " join last_name on main.last_name = last_name_id"
                    " join first_name on main.first_name = first_name_id"
                    " join middle_name on main.middle_name = middle_name_id"
                    " join discipline on main.discipline = discipline_id"
                    " WHERE uid = %s", (uid,))
        student = cur.fetchone()
        if student is None:
            return {'message': 'Student not found'}, 404
        def convert(data):
            return {
                'uid': data[0],
                'last_name': data[1],
                'first_name': data[2],
                'middle_name': data[3],
                'discipline': data[4],
                'mark': data[5]
            }
        student = convert(student)
        return student

    def delete(self, uid):
        db = get_db()
        cur = db.cursor()
        cur.execute("SELECT uid FROM main WHERE uid = %s", (uid,))
        student = cur.fetchone()
        if student is None:
            return {'message': 'Student not found'}, 404
        cur.execute("DELETE FROM main WHERE uid = %s", (uid,))
        db.commit()
        return {'message': 'Student deleted'}

    def put(self, uid):
        parser = reqparse.RequestParser()
        parser.add_argument('last_name')
        parser.add_argument('first_name')
        parser.add_argument('middle_name')
        parser.add_argument('discipline')
        parser.add_argument('mark')
        args = parser.parse_args()

        db = get_db()
        cur = db.cursor()
        cur.execute("SELECT uid FROM main WHERE uid = %s", (uid,))
        student = cur.fetchone()
        if student is None:
            return {'message': 'Student not found'}, 404

        if args['last_name'] is not None:
            cur.execute("SELECT last_name_id FROM last_name WHERE last_name_val = %s", (args['last_name'],))
            last_name = cur.fetchone()
            if last_name is None:
                cur.execute("INSERT INTO last_name (last_name_val) VALUES (%s)", (args['last_name'],))
                cur.execute("SELECT last_name_id FROM last_name WHERE last_name_val = %s", (args['last_name'],))
                last_name = cur.fetchone()
                last_name = last_name[0]
            else:
                last_name = last_name[0]
            cur.execute("UPDATE main SET last_name = %s WHERE uid = %s", (last_name, uid))

        if args['first_name'] is not None:
            cur.execute("SELECT first_name_id FROM first_name WHERE first_name_val = %s", (args['first_name'],))
            first_name = cur.fetchone()
            if first_name is None:
                cur.execute("INSERT INTO first_name (first_name_val) VALUES (%s)", (args['first_name'],))
                cur.execute("SELECT first_name_id FROM first_name WHERE first_name_val = %s", (args['first_name'],))
                first_name = cur.fetchone()
                first_name = first_name[0]
            else:
                first_name = first_name[0]
            cur.execute("UPDATE main SET first_name = %s WHERE uid = %s", (first_name, uid))

        if args['middle_name'] is not None:
            cur.execute("SELECT middle_name_id FROM middle_name WHERE middle_name_val = %s", (args['middle_name'],))
            middle_name = cur.fetchone()
            if middle_name is None:
                cur.execute("INSERT INTO middle_name (middle_name_val) VALUES (%s)", (args['middle_name'],))
                cur.execute("SELECT middle_name_id FROM middle_name WHERE middle_name_val = %s", (args['middle_name'],))
                middle_name = cur.fetchone()
                middle_name = middle_name[0]
            else:
                middle_name = middle_name[0]
            cur.execute("UPDATE main SET middle_name = %s WHERE uid = %s", (middle_name, uid))

        if args['discipline'] is not None:
            cur.execute("SELECT discipline_id FROM discipline WHERE discipline_val = %s", (args['discipline'],))
            discipline = cur.fetchone()
            if discipline is None:
                cur.execute("INSERT INTO discipline (discipline_val) VALUES (%s)", (args['discipline'],))
                cur.execute("SELECT discipline_id FROM discipline WHERE discipline_val = %s", (args['discipline'],))
                discipline = cur.fetchone()
                discipline = discipline[0]
            else:
                discipline = discipline[0]
            cur.execute("UPDATE main SET discipline = %s WHERE uid = %s", (discipline, uid))

        if args['mark'] is not None:
            cur.execute("UPDATE main SET mark = %s WHERE uid = %s", (args['mark'], uid))

        db.commit()
        return {'message': 'Student updated'}