BOARDS/CARDPUTER CircuitPython/projects/text_editor.py

# GUIDE
# type freely! CTRL+D clears the text.
# backspace, space, and return function as expected.
# keys not recognised WILL print "UNKNOWN 0x??", but this is useful for extra key scans
#
# WORK IN PROGRESS
# CTRL + S to save text to the SD Card
# CTRL + O to open a text file
# UP and DOWN scrolling - (use cursor )
######

import board
import terminalio
from adafruit_display_text import label
from keyboard import Keyboard

import busio
import sdcardio
import storage
import os

def save_file():
    save_text = "save file"
    save_group = label.Label(terminalio.FONT, text=save_text)
    save_group.x = 10
    save_group.y = 10
    board.DISPLAY.root_group = save_group

def open_file():
    open_text = "open file"
    open_group = label.Label(terminalio.FONT, text=open_text)
    open_group.x = 10
    open_group.y = 10
    board.DISPLAY.root_group = open_group

def editor(text):
    if page == "editor":
        ## WRAPPING
        ## calculate wrapping when entering a character 
        lines = text.split("\n")
        current_line = lines[len(lines)-1]
        if len(current_line) > 35:
            text=text+"\n" # <- start a new line here
        ##############################################
        text = text+key
        text_area.text = text
    return text

def esc():
    if page == "editor":
        pass
    elif page == "save" or page == "open":
        board.DISPLAY.root_group = intro_text_area

## SD Card set up for saving text to SD card
spi = busio.SPI(board.SD_SCK, MOSI=board.SD_MOSI, MISO=board.SD_MISO)
cs = board.SD_CS

try:
    sdcard = sdcardio.SDCard(spi, cs)
    vfs = storage.VfsFat(sdcard)

    storage.mount(vfs, "/sd") # access files on sd card here
    SD_status = "SD Card Mounted"
except OSError:
    SD_status = "No SD card found"
    pass # SD card not inserted/found
#########################################

keyb = Keyboard()

page = "editor"

intro_text = "Press CTRL+D to clear text\n"+SD_status+"\n\n"
intro_text_area = label.Label(terminalio.FONT, text=intro_text, color="C3B")
intro_text_area.x = 10
intro_text_area.y = 10

text = ""
text_area = label.Label(terminalio.FONT, text=text)
text_area.x = 0
text_area.y = 40

board.DISPLAY.root_group = intro_text_area
intro_text_area.append(text_area)

while True:
    key = keyb.scan()
    if key == "BACKSP":
        text = text[:-1] 
    elif key == "CTRLD":
        text = ""
    elif key == "CTRLS":
        save_file()
        page = "save"
    elif key == "CTRLO":
        open_file()
        page="open"
    elif key == "ESC":
        esc()
        page = "editor"
    else:
        text = editor(text)