from machine import Pin
import time
stepping = [[1,0,1,0],[1,0,0,0],[1,0,0,1],[0,0,0,1],[0,1,0,1],[0,1,0,0],[0,1,1,0],[0,0,1,0]]

class Stepper:
    def __init__(self,pins,stepsPerRev=400):
        self._pins = [Pin(p, Pin.OUT) for p in  pins]
        self.stepnum = 0
        self.rotDirection = 1
        self.rotTarget = 0
        self.stepDuration = 0.05
        self._lastStepTime = time.time()
        self.stepsPerRev=stepsPerRev

    def _setPins(self,level):
        self._pins[0].value(level[0])
        self._pins[1].value(level[1])
        self._pins[2].value(level[2])
        self._pins[3].value(level[3])

    def doSteppsBlock(self,num,speed=0.05):
        for i in range(num):
            self.stepnum = (self.stepnum + 1)
            self._setPins(stepping[self.stepnum%8])
            time.sleep(speed)
        self.disablePower()

    def rotateTo(self, target,direction=0):
        """sets the rotation target and (if direction == 0) calculates if
        it should rotate left or right"""
        self.rotTarget = int(target*self.stepsPerRev) % self.stepsPerRev
        if (direction == 0):
            self.rotDirection = 1 if (self.stepnum- self.rotTarget)%self.stepsPerRev \
                > self.stepsPerRev/2 else 0
        else:
            self.rotDirection = direction

    def update(self):
        if (self.rotTarget%self.stepsPerRev != self.stepnum%self.stepsPerRev) \
                and not self.isMoving():
            self._lastStepTime = time.ticks_ms()
            self.stepnum = (self.stepnum + self.rotDirection) % self.stepsPerRev
            self._setPins(stepping[self.stepnum%8])
            #time.sleep(speed)

    def disablePower(self):
        self._setPins([0,0,0,0])

    def isMoving(self):
        return time.ticks_diff(time.ticks_ms(), self._lastStepTime) <= self.stepDuration

    def isAtTarget(self):
        return (not self.isMoving()) \
            and (self.rotTarget%self.stepsPerRev == self.stepnum%self.stepsPerRev)