import serial
import os
import time 
chunksize=4096

#LOG0002   
#32 = 124 kbps
#128 = 263 kbps
#4096 = 416 kbps
#32768 = 427 kbps
#65536 = failed

serialport = serial.Serial(port='/dev/ttyACM0', baudrate=115200, timeout=1)

def establish_connection():

    serialport.write("\n".encode())
    

    serialport.write("echo off\n".encode())
    while len(serialport.readline())>0:
        continue
    

    serialport.write("test\n".encode())
    response = serialport.readline()
    hrresponse=response.rstrip().decode('ascii')
    if hrresponse != "OK":
        print("Unexpected test response:"+str(response))
        exit()

def get_filenames():

    filenames=[]

    serialport.write("ls\n".encode())
    while True:            
            response = serialport.readline()
            hrresponse=response.rstrip().decode('ascii')
            if(len(response))>0:
                #print(hrresponse)
                filenames.append(hrresponse)
                
            else:
                break

    return filenames


def get_filesize(filename):

    filesize=0

    serialport.write(("sizeof "+str(filename)+"\n").encode())
    
    response = serialport.readline()
    hrresponse=response.rstrip().decode('ascii')
    if(len(response))>0:
        filesize=int(hrresponse)
        
    return filesize


def copy_file(source,destination,expectedsize):
    os.makedirs(os.path.dirname(writefilename), exist_ok=True)

            
    transferstarttime=time.time()
    chunkstarttime=time.time()
    last_print=time.time()

    with open(writefilename, 'wb') as writer:
        serialport.write(("chunksize "+str(chunksize)+"\n").encode())
        serialport.write(("get "+filename+"\n").encode())
                    

        acc_datalen=0

        while True:
            
            '''
            response = serialport.readline()
            hrresponse=response.rstrip().decode('ascii')
            if(len(response))>0:
                #print(hrresponse)
                writer.write(response)
                
            else:
                break
            '''

            
            data=serialport.read(chunksize)
            
            if(len(data))>0: #data received
                #print("received "+str(len(data))+" bytes")
                #hrresponse=data.rstrip().decode('ascii')
                #print(hrresponse)

                acc_datalen+=len(data)

                checksum=(sum(data) & 0xFF)
                checksumarray=bytearray([checksum])

                writer.write(data)
                serialport.write(checksumarray) #request next chunk by sending checksum of last chunk        
                
            else:
                break


            if (time.time()-last_print>0.5):
                last_print=time.time()
                chunkduration=time.time()-chunkstarttime
                chunkstarttime=time.time()
                progress=acc_datalen/expectedsize
                print(str(round(progress*100,0))+"% \t"+str(round(chunkduration*1000,3))+" ms for "+str(len(data))+" Byte \t = "+str(round((len(data)/chunkduration)/1000,3))+" kB/s")


    fileduration=time.time()-transferstarttime
        
    file_stats=os.stat(writefilename)
    print("Finished transfer of "+str(acc_datalen)+" B or "+str(file_stats.st_size)+" (os) Byte in "+str(fileduration)+" s \t = "+str(round(file_stats.st_size/fileduration/1000,3))+" kB/s") 


    return acc_datalen




def log_off():
    serialport.write(("log off\n").encode())
    response = serialport.readline()
    hrresponse=response.rstrip().decode('ascii')
    if (not hrresponse.startswith("Log disabled")):
        print("Unexpected response:"+str(response))
        exit()

def delete_file(filename):       
    
    
    serialport.write(("rm "+filename+"\n").encode())
    response = serialport.readline()
    hrresponse=response.rstrip().decode('ascii')
    if hrresponse != "OK":
        print("Unexpected response:"+str(response))
        exit()


if serialport.isOpen():
    
    establish_connection()
    


    #Get File List
    filenames=get_filenames()


    #Copy all Files    
    failed=0
    
    for filename in filenames:
        print("Reading file "+filename)
        expectedsize=get_filesize(filename)
        print("Expecting "+str(expectedsize)+" Byte")

        writefilename='sdcard/'+filename
        receivedsize=copy_file(filename,writefilename,expectedsize)
        
        if (expectedsize!=receivedsize):
            print("Warning: Filesize does not match!")
            failed+=1

        print("")

    print(str(len(filenames))+" Files copied with "+str(failed)+" failed")
    
    

    #Delete all files
    '''
    log_off()
    for filename in filenames:
        delete_file(filename)
    '''

    


serialport.write("echo on\n".encode())


    

serialport.close()