# -*- coding: utf-8 -*-
import json, pymysql

conn = pymysql.connect(
db='test',
user='ksv',
passwd='1234567890',
host='kis',
charset='utf8')
c = conn.cursor()


def createTables(tbl_list):
    global tbl_descr_list, tbl_struct_list
    i = 0
    tbl_names_list = []
    tbl_descr_list = []
    tbl_struct_list = []

    while i < len(tbl_list):
        one_Table_descr = []
        one_Table_struct = []
        one_Table_relation = []
        tbl_descr = tbl_list[i]["tableDescription"]
        tbl_name = tbl_list[i]["tableName"]
        #field_list = tbl_list[i]["fieldList"][i].keys()
        tbl_names_list.append([tbl_name, tbl_descr])
        one_Table_descr.append(tbl_name)
        one_Table_struct.append(tbl_name)

        x = 0
        # список всех полей таблицы
        qwery_create = "CREATE TABLE IF NOT EXISTS " + tbl_name + " ("
        index = ""
        field_names_list = []
        struct_fields_list = []
        while x < len(tbl_list[i]["fieldList"]):
            if tbl_list[i]["fieldList"][x]["autoIncrement"] == "yes":
                auto_increment = " AUTO_INCREMENT, "
            else:
                auto_increment = ", "
            qwery_create = qwery_create + tbl_list[i]["fieldList"][x]["fName"] + " " + \
                           tbl_list[i]["fieldList"][x]["fType"] + auto_increment
            if tbl_list[i]["fieldList"][x]["index"] == "PRIMARY KEY":
                index = "PRIMARY KEY(" + tbl_list[i]["fieldList"][x]["fName"] + ")"
            field_names_list.append(tbl_list[i]["fieldList"][x]["fDescription"])
            struct_fields_list.append(tbl_list[i]["fieldList"][x]["fName"])
            if tbl_list[i]["fieldList"][x]["relation"]:
                relation_list=[tbl_list[i]["fieldList"][x]["fName"]]
                relation_list.append(tbl_list[i]["fieldList"][x]["relation"])

                one_Table_relation.append(relation_list)
            x = x + 1

        qwery_create = qwery_create + index + ");"
        one_Table_struct.append(struct_fields_list)
        one_Table_struct.append(one_Table_relation)
        one_Table_descr.append(field_names_list)
        i = i + 1
        tbl_descr_list.append(one_Table_descr)
        tbl_struct_list.append(one_Table_struct)
        c.execute(qwery_create)
    return tbl_names_list

def initDBstructure():
    global tbl_descr_list
    table_list = open("tables.json", "r", encoding="utf-8")
    data = json.load(table_list, encoding="utf-8")
    tbl_list = data["tables"]
    tbl_names_list = createTables(tbl_list)

    return tbl_names_list

# выборка данных из заданной таблицы
def selectData(tbl):
    global tbl_struct_list
    # если юольше 1 поля добавить CONCAT
    qwery = "SELECT "
    subqwery = ""
    for item in tbl_struct_list:
        if item[0] == tbl:
            for field in item[1]:
                qwery = qwery + field + ","
            for rel in item[2]:
                field = rel[0]
                field_rel = rel[1][0]
                field_replace = rel[1][1]
                field_replace = field_replace.replace(",", ",' ',")
                # определяем название таблицы для вложенного запроса
                table1 = field_rel.split('.')[0]
                field1 = field_rel.split('.')[1]
                if table1 == tbl:
                    table1 = table1 + "_1"
                    subqwery = tbl + " AS " +table1
                else:
                    subqwery = table1
                # составляем подзапрос и подменяем им поле в запросе
                subqwery = "(SELECT CONCAT(" + field_replace + ") FROM " + subqwery +" WHERE "+ table1 + "." + field1 +"="+ tbl +"."+ field +") AS " + field
                qwery = qwery.replace(field, subqwery)
    qwery = qwery.rstrip(',') + " FROM " + tbl + " LIMIT 10000"
    c.execute(qwery)

    return c.fetchall()

# получаем на вход имя таблицы и возвращаем список заголовков полей
def getTablesStructure(tbl):
    global tbl_descr_list
    for item in tbl_descr_list:
        if item[0] == tbl:
            return item[1]

#initDBstructure()