import re
from app import schemas
from datetime import datetime
from datetime import timedelta
from datetime import timezone
import croniter

from configs.settings import config

hour_min = config.get('CRON_CONFIG', 'hour_min')
hour_max = config.get('CRON_CONFIG', 'hour_max')
enable = config.get('CRON_CONFIG', 'enable')


def joint_cron_expression(item: schemas.CronExpression):
    cron = ""
    if item.cron_select_type == 0:
        if item.minute is not None:
            cron += '0/'+str(item.minute) + ' *'
        elif item.hour is not None:
            cron += '0 4-22/'+str(item.hour)
        else: cron += '*'
        cron += ' * * *'
    elif item.cron_select_type == 1:
        if item.minute is not None:
            cron += str(item.minute)
        else: cron += '*'
        cron += ' '
        if item.hour is not None:
            cron += str(item.hour)
        else: cron += '*'
        cron += ' * * *'
    elif item.cron_select_type == 2:
        if item.minute is not None:
            cron += str(item.minute)
        else: cron += '*'
        cron += ' '
        if item.hour is not None:
            cron += str(item.hour)
        else: cron += '*'
        if item.week is not None:
            cron += ' ? * '
            cron += str(item.week)
        else: cron += ' * * *'
    elif item.cron_select_type == 3:
        if item.minute is not None:
            cron += str(item.minute)
        else: cron += '*'
        cron += ' '
        if item.hour is not None:
            cron += str(item.hour)
        else: cron += '*'
        cron += ' '
        if item.day is not None:
            cron += str(item.day)
        else: cron += '*'
        cron += ' '
        if item.month is not None:
            cron += '1/'+str(item.month)
        else: cron += '*'
        if item.day is not None:
            cron += ' ?'
        else: cron += ' *'
    else:
        cron = item.cron_expression
    check_cron_expression(cron)
    if enable == '1': check_cron_hour(cron)
    return cron

# 不允许隔小时、分钟
enable_section_reg_list = [
    "^(([0-9]|[0-5][0-9]))$",
    "^(([0-9]|[1][0-9]|2[0-3]))$",
    "^((([1-9]|[1-2][0-9]|3[01])(\\,|\\-|\\/){1}([1-9]|[1-2][0-9]|3[01]))|([1-9]|[1-2][0-9]|3[01])|(\\*)|(\\?))$",
    "^((([1-9]|[1][0-2])(\\,|\\-|\\/){1}([1-9]|[1][0-2]))|([1-9]|[1][0-2])|(\\*))$",
    "^((([1-7])(\\,|\\-|\\/){1}([1-7]))|([1-7])|(\\*)|(\\?))$"
]

# 允许隔小时分钟
no_section_reg_list = [
    "^((([0-9]|[1-5][0-9])(\\,|\\-|\\/){1}([1-9]|[1-5][0-9]))|([0-9]|[0-5][0-9])|(\\*))$",
    "^((([0-9]|[1][0-9]|2[0-3])(\\,|\\-|\\/){1}([1-9]|[1][0-9]|2[0-3]))|([0-9]|[1][0-9]|2[0-3])|(\\*))$",
    "^((([1-9]|[1-2][0-9]|3[01])(\\,|\\-|\\/){1}([1-9]|[1-2][0-9]|3[01]))|([1-9]|[1-2][0-9]|3[01])|(\\*)|(\\?))$",
    "^((([1-9]|[1][0-2])(\\,|\\-|\\/){1}([1-9]|[1][0-2]))|([1-9]|[1][0-2])|(\\*))$",
    "^((([1-7])(\\,|\\-|\\/){1}([1-7]))|([1-7])|(\\*)|(\\?))$"
]


def check_cron_expression(cron_expression):
    cron_list = cron_expression.split(' ')
    unit_list = ['minute', 'hour', 'day', 'month', 'week']
    reg_list = no_section_reg_list if enable == '0' else enable_section_reg_list
    for cron, unit, reg in zip(cron_list, unit_list, reg_list):
        match_obj = re.match(reg, cron)
        if match_obj is None:
            raise Exception(f'在{unit}的位置上，数据校验错误')

def parsing_cron_expression(cron_expression):
    cron_list = cron_expression.split(' ')
    unit_list = ['minute', 'hour', 'day', 'month', 'week']
    cron_dict = {}
    for cron, unit in zip(cron_list, unit_list):
        if not bool(re.match('^((\\*)|(\\?))$',cron)):
            cron_dict.update({unit: cron.replace('0/','').replace('1/','')})
    return cron_dict

def check_cron_hour(cron_expression):
    cron_list = cron_expression.split(' ')
    unit_list = ['minute', 'hour', 'day', 'month', 'week']
    for cron, unit in zip(cron_list, unit_list):
        if unit == 'hour':
            if int(cron) < int(hour_min) or int(cron) > int(hour_max)-1:
                raise Exception(f'执行时间必须在每日{hour_min}～{hour_max}时之间')

def run_get_next_time(cron_expression):
    SHA_TZ = timezone(timedelta(hours=8),name='Asia/Shanghai',)
    utc_now = datetime.utcnow().replace(tzinfo=timezone.utc)
    now = utc_now.astimezone(SHA_TZ)
    cron_str = cron_expression.replace('?','*')
    cron = croniter.croniter(cron_str, now)
    execute_list = []
    for i in range(0, 5):
        next_time = cron.get_next(datetime).strftime("%Y-%m-%d %H:%M")
        execute_list.append(next_time)
    return execute_list