from pyheatpump.db import DB, RowClass

from pyheatpump.logger import logger_init
logger = logger_init()

class VariableType(RowClass):
    slabel: str = '' 
    label: str = '' 
    type: str = '' 
    start_address: int = None
    end_address: int = None

    def __init__(self, **kwargs):
        super().__init__(**kwargs)

        if self.slabel is None and self.label is not None:
            self.slabel = self.label[0]


    def __str__(self):
        return self.slabel or self.label[0]


    def cast(self):
        # Function to convert numbers > 2**15 to negative numbers (issue #30)
        #complement = lambda x: x - (1 << 16 if x & (1 << 15) else 0)
        complement = lambda x: x - (1 << 16) if x >> 15 else x
        #complement = lambda x: int.from_bytes(bytes(x), 'big', signed=True)

        if self.type == 'bool':
            # returns a boolean
            return lambda x: x % 2
        elif self.type == 'float':
            # returns a signed float
            return lambda x: round(complement(x) / 10, 2)
        elif self.type == 'int':
            # returns the signed integer
            return lambda x: int(complement(x))

        return None

    def select(self):
        try:
            elt = next(super().select('slabel', 'var_type'))
        except StopIteration:
            logger.error('VariableType.select(%s, %s): does not exist')
        return elt


    def save(self):
        q = ['UPDATE var_type SET']
        updates = []
        if self.start_address is not None:
            updates.append(f'start_address = {self.start_address}')
        if self.end_address is not None:
            updates.append(f'end_address = {self.end_address}')
        if len(updates) == 0:
            return False
        q.append(','.join(updates))
        q.append(f"WHERE slabel = {self.slabel}'")

        return DB.sql(' '.join(q), self.__dict__)


    def get_variables(self):
        from .variable import Variable
        return Variable.getall_of_type(self)

    def get_variables_values(self):
        from .variable import Variable
        values = Variable.getall_values_of_type(self)
        res = {}
        for address, variable in values.items():
            logger.debug('address: %s, start_addres: %s, calc: %s',
                address, self.start_address, address - self.start_address + 1)
            res[str(address - self.start_address + 1)] = variable
        return res


    def get_variables_values_since(self, since: int):
        from .variable import Variable
        res = {}
        values = Variable.getall_values_of_type_since(self, since)
        for address, variable in values.items():
            logger.debug('address: %s, start_addres: %s, calc: %s',
                address, self.start_address, address - self.start_address + 1)
            res[str(address - self.start_address + 1)] = variable
        return res


    def control(self, data):
        from .variable import Variable
        from .variable_value import VariableValue

        for s_address, s_value in data.items():
            address = int(s_address)
            if self.slabel == 'I':
                # For integers, we have to respect the offset to get the address
                address = address + self.start_address - 1

            # All values are stored in strings that represent floats
            # We have to convert them
            f_value = float(s_value)

            if self.slabel == 'A':
                f_value = f_value * 10

            # Value is stored as integers in database
            value = int(f_value)

            if not Variable(**{
                    'type': self,
                    'address': address}).exists():
                continue

            new_var_value = VariableValue(**{
                'type': self,
                'address': address,
                'value': value})

            old_var_value = VariableValue.get(
                self, address)

            if old_var_value.equals(new_var_value):
                continue

            new_var_value.set()

    @staticmethod
    def getall():
        return {
            row['label']: VariableType(**dict(row))
            for row in DB.sql('SELECT * FROM var_type')
        }

    @staticmethod
    def get(slabel: str):
        if len(slabel) > 1:
            slabel = slabel[0]

        try:
            return VariableType(**dict(
                next(DB.sql(
                """
                SELECT * FROM var_type
                WHERE slabel = ?
                """, slabel))))
        except StopIteration as exc:
            raise NameError from exc