# 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

## 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", readonly=False) # 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 = 30

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

filename_text = ""
save_text = "Save File - Enter Filename\nOverwriting Enabled"
save_group = label.Label(terminalio.FONT, text=save_text, color="C3B")
save_group.x = 10
save_group.y = 10
filename_group = label.Label(terminalio.FONT, text=filename_text)
filename_group.x = 0
filename_group.y = 60
save_group.append(filename_group)

files_text = ""
open_text = "Open File - Select using arrow keys"
open_group = label.Label(terminalio.FONT, text=open_text, color="C3B")
open_group.x = 10
open_group.y = 10
files_group = label.Label(terminalio.FONT, text=files_text)
files_group.x = 0
files_group.y = 30
open_group.append(files_group)

open_cursor = 0

while True:
    key = keyb.scan()
    
    if key == "BACKSP":
        if page == "editor":
            text = text[:-1]
            text_area.text = text
        elif page == "save":
            filename_text = filename_text[:-1]
            filename_group.text = filename_text
        
    elif key == "CTRLD":
        if page == "editor":
            text = ""
            text_area.text = text
        elif page == "save":
            filename_text = ""
            filename_group.text = filename_text
        
    elif key == "CTRLS":
        board.DISPLAY.root_group = save_group
        page = "save"
        filename_group.text=filename_text
        
    elif key == "CTRLO":
        board.DISPLAY.root_group = open_group
        page="open"
        files_text = ""
        index = 0
        for file in os.listdir("/sd"):
            filename = str(file)
            if index == open_cursor:
                filename = "> " + filename
            files_text = files_text + filename+"\n"
            index += 1
        files_group.text = files_text
        
    elif key == "ESC":
        if page == "editor":
            pass
        elif page == "save" or page == "open":
            board.DISPLAY.root_group = intro_text_area
        page = "editor"

        
    else:
        ## The actual editor
        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

        ## The save file menu - for typing the filename
        elif page == "save":
            if key == "DOWN":
                filename_text = filename_text + "."
                filename_group.text = filename_text
            elif key == "\n":
                with open("/sd/"+filename_text, "w") as f:
                    f.write(text)
                    f.close()
                board.DISPLAY.root_group = intro_text_area
                page = "editor"
            elif not keyb.is_alphanumeric(key):
                pass # dont allow special characters to be entered
            else:
                filename_text = filename_text+key
                filename_group.text=filename_text

        ## The open file menu - for selecting a file
        elif page == "open":
            pass