# wemos_flash.py Test flash chips with ESP8266 host

# Released under the MIT License (MIT). See LICENSE.
# Copyright (c) 2020 Peter Hinch

import uos
from machine import SPI, Pin
from flash_spi import FLASH

cspins = (Pin(5, Pin.OUT, value=1), Pin(14, Pin.OUT, value=1))

spi = SPI(-1, baudrate=20_000_000, sck=Pin(4), miso=Pin(0), mosi=Pin(2))


def get_flash():
    flash = FLASH(spi, cspins)
    print("Instantiated Flash")
    return flash


directory = "/fl_ext"
a = bytearray(range(256))  # Data to write
b = bytearray(256)  # Data to read back
files = {}  # n:length
errors = 0


def fname(n):
    return "{}/{:05d}".format(directory, n + 1)  # Names start 00001


def fcreate(n):  # Create a binary file of random length
    length = int.from_bytes(uos.urandom(2), "little") + 1  # 1-65536 bytes
    linit = length
    with open(fname(n), "wb") as f:
        while length:
            nw = min(length, 256)
            f.write(a[:nw])
            length -= nw
    files[n] = length
    return linit


def fcheck(n):
    length = files[n]
    with open(fname(n), "rb") as f:
        while length:
            nr = f.readinto(b)
            if not nr:
                return False
            if a[:nr] != b[:nr]:
                return False
            length -= nr
    return True


def check_all():
    global errors
    for n in files:
        if fcheck(n):
            print("File {:d} OK".format(n))
        else:
            print("Error in file", n)
            errors += 1
    print("Total errors:", errors)


def remove_all():
    for n in files:
        uos.remove(fname(n))


def flash_test(format=False):
    eep = get_flash()
    if format:
        uos.VfsLfs2.mkfs(eep)
    try:
        uos.mount(eep, "/fl_ext")
    except OSError:  # Already mounted
        pass
    for n in range(128):
        length = fcreate(n)
        print("Created", n, length)
    print("Created files", files)
    check_all()
    for _ in range(100):
        for x in range(5):  # Rewrite 5 files with new lengths
            n = int.from_bytes(uos.urandom(1), "little") & 0x7F
            length = fcreate(n)
            print("Rewrote", n, length)
        check_all()
    remove_all()


msg = """Run wemos_flash.flash_test(True) to format new array, otherwise
wemos_flash.flash_test()
Runs prolonged test of filesystem."""
print(msg)