#!/bin/python3

import random
from bitarray import bitarray
from bitarray.util import zeros
from dht.hashes import Hash

class Block:
    """This class represents a block in the Ethereum blockchain."""

    def __init__(self, blockSize):
        """Initialize the block with a data array of blocksize^2 zeros."""
        self.blockSize = blockSize
        self.data = zeros(self.blockSize*self.blockSize)

    def fill(self):
        """It fills the block data with ones."""
        self.data.setall(1)

    def merge(self, merged):
        """It merges (OR) the existing block with the received one."""
        self.data |= merged.data

    def getSegment(self, rowID, columnID):
        """Check whether a segment is included"""
        return self.data[rowID*self.blockSize + columnID]

    def setSegment(self, rowID, columnID, value = 1):
        """Set value for a segment (default 1)"""
        self.data[rowID*self.blockSize + columnID] = value

    def getColumn(self, columnID):
        """It returns the block column corresponding to columnID."""
        return self.data[columnID::self.blockSize]

    def mergeColumn(self, columnID, column):
        """It merges (OR) the existing column with the received one."""
        self.data[columnID::self.blockSize] |= column

    def repairColumn(self, id):
        """It repairs the entire column if it has at least blockSize/2 ones.
            Returns: list of repaired segments
        """
        line = self.data[id::self.blockSize]
        success = line.count(1)
        if success >= self.blockSize/2:
            ret = ~line
            self.data[id::self.blockSize] = 1
        else:
            ret = zeros(self.blockSize)
        return ret

    def getRow(self, rowID):
        """It returns the block row corresponding to rowID."""
        return self.data[rowID*self.blockSize:(rowID+1)*self.blockSize]

    def mergeRow(self, rowID, row):
        """It merges (OR) the existing row with the received one."""
        self.data[rowID*self.blockSize:(rowID+1)*self.blockSize] |= row

    def repairRow(self, id):
        """It repairs the entire row if it has at least blockSize/2 ones.
            Returns: list of repaired segments.
        """
        line = self.data[id*self.blockSize:(id+1)*self.blockSize]
        success = line.count(1)
        if success >= self.blockSize/2:
            ret = ~line
            self.data[id*self.blockSize:(id+1)*self.blockSize] = 1
        else:
            ret = zeros(self.blockSize)
        return ret

    def print(self):
        """It prints the block in the terminal (outside of the logger rules))."""
        dash = "-" * (self.blockSize+2)
        print(dash)
        for i in range(self.blockSize):
            line = "|"
            for j in range(self.blockSize):
                line += "%i" % self.data[(i*self.blockSize)+j]
            print(line+"|")
        print(dash)


    # --- DHT Related ---
    def getUniqueIDforSegment(self, rowID, columnID):
        """It returns a unique ID for a segment indicating its coordinates in the block"""
        return f"r{rowID}-c{columnID}"

    def getSegmentHash(self, rowID, columnID):
        """It generates the Hash that will be used to identify the segment in the DHT.

        This includes matching the uniqueID based on the row and the column
        with the actual value of the segment.
        """
        segmentID = self.getUniqueIDforSegment(rowID, columnID) + f"x{self.getSegment(rowID, columnID)}"
        return Hash(segmentID)