From b539f42b87a4e3a1312442c1d54ddc848d39774c Mon Sep 17 00:00:00 2001
From: KemoNine <kemonine@kemonine.info>
Date: Sun, 16 Aug 2020 01:52:21 -0400
Subject: [PATCH] Add slidshow album controls

---
 docs/lcd_controls.md |  33 +++++++
 docs/slideshow.md    |   6 +-
 lcd_controls.py      | 222 +++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 260 insertions(+), 1 deletion(-)
 create mode 100644 docs/lcd_controls.md
 create mode 100644 lcd_controls.py

diff --git a/docs/lcd_controls.md b/docs/lcd_controls.md
new file mode 100644
index 0000000..7b79460
--- /dev/null
+++ b/docs/lcd_controls.md
@@ -0,0 +1,33 @@
+# LCD Controls
+
+The below will setup an Adafruit mini LCD with 2 buttons as a controller for selecting which photo albums are displayed on a PiFrame. This setup also includes the Adafruit stemma/qwiic LUX sensor setup which will be integrated further in the future.
+
+``` sh
+
+apt install -y python3-pip ttf-dejavu python3-pil python3-numpy
+
+pip3 install adafruit-circuitpython-rgb-display adafruit-circuitpython-bh1750 RPI.GPIO
+pip3 install --upgrade --force-reinstall spidev
+
+git clone https://git.kemonine.info/kemonine/piframe.git /opt/piframe
+cp /opt/piframe/lcd_control.py /usr/local/bin/
+chmod a+x /usr/local/bin/lcd_control.py
+cat > /etc/systemd/system/lcd_control.service <<EOF
+[Unit]
+Description=Control which album is shown as a slideshow
+After=fim.service
+
+[Service]
+Type=simple
+User=root
+ExecStart=/usr/local/bin/lcd_control.py
+TimeoutSec=15
+Restart=always
+
+[Install]
+WantedBy=multi-user.target
+EOF
+systemctl daemon-reload
+systemctl enable --now lcd_control
+
+```
diff --git a/docs/slideshow.md b/docs/slideshow.md
index 3ac5e44..9293d96 100644
--- a/docs/slideshow.md
+++ b/docs/slideshow.md
@@ -168,8 +168,12 @@ unbind "|";
 unbind "}";
 unbind "~";
 EOF
+cat > /etc/default/fim_album_path <<EOF
+/tank/pictures
+EOF
 cat > /usr/local/bin/fim-slideshow.sh <<EOF
 #!/bin/bash
+ALBUM_PATH=\`cat /etc/default/fim_album_path\`
 # options inspiration: https://www.raspberrypi.org/forums/viewtopic.php?t=196043
 tput civis
 /usr/bin/fim --verbose --no-commandline --no-history \
@@ -178,7 +182,7 @@ tput civis
 --execute-commands 'while(1){display;sleep "300";next;}' \
 --autozoom --random \
 --cd-and-readdir --recursive \
-/tank/pictures
+"\$ALBUM_PATH"
 EOF
 chmod a+x /usr/local/bin/fim-slideshow.sh
 cat > /etc/systemd/system/fim.service <<EOF
diff --git a/lcd_controls.py b/lcd_controls.py
new file mode 100644
index 0000000..be19016
--- /dev/null
+++ b/lcd_controls.py
@@ -0,0 +1,222 @@
+#!/usr/bin/python3
+# -*- coding: utf-8 -*-
+
+####################
+# Inspiration / Further Reading
+####################
+# https://circuitpython.readthedocs.io/projects/bh1750/en/latest/
+# https://raspi.tv/2013/how-to-use-interrupts-with-python-on-the-raspberry-pi-and-rpi-gpio-part-3
+# https://stackoverflow.com/questions/16148735/how-to-implement-a-watchdog-timer-in-python
+# https://learn.adafruit.com/adafruit-bh1750-ambient-light-sensor
+# https://learn.adafruit.com/adafruit-mini-pitft-135x240-color-tft-add-on-for-raspberry-pi/overview
+
+import board
+import busio
+import dbus
+import digitalio
+import os
+import time
+from threading import Timer
+from PIL import Image, ImageDraw, ImageFont
+import RPi.GPIO as GPIO
+import adafruit_rgb_display.st7789 as st7789
+import adafruit_bh1750
+
+# Generic watchdog timer used for backlight controls
+class Watchdog:
+    def __init__(self, timeout, userHandler=None):  # timeout in seconds
+        self.timeout = timeout
+        self.handler = userHandler if userHandler is not None else self.defaultHandler
+        self.timer = Timer(self.timeout, self.handler)
+        # Do NOT start timer by default ; we want this triggered by reset events that come through
+        #     via the inotify filesystem watcher
+        #self.timer.start()
+
+    def reset(self):
+        self.timer.cancel()
+        self.timer = Timer(self.timeout, self.handler)
+        self.timer.start()
+
+    def stop(self):
+        self.timer.cancel()
+
+    def defaultHandler(self):
+        raise self
+
+# Cheat for walking only one level deep via os.walk (faster than other options)
+def walklevel(some_dir, level=1):
+    some_dir = some_dir.rstrip(os.path.sep)
+    assert os.path.isdir(some_dir)
+    num_sep = some_dir.count(os.path.sep)
+    for root, dirs, files in os.walk(some_dir):
+        yield root, dirs, files
+        num_sep_this = root.count(os.path.sep)
+        if num_sep + level <= num_sep_this:
+            del dirs[:]
+
+# bh1740 lux sensor
+i2c = busio.I2C(board.SCL, board.SDA)
+sensor = adafruit_bh1750.BH1750(i2c)
+
+# Configuration for CS and DC pins (these are FeatherWing defaults on M0/M4):
+cs_pin = digitalio.DigitalInOut(board.CE0)
+dc_pin = digitalio.DigitalInOut(board.D25)
+reset_pin = None
+
+# Setup button pins as inputs
+GPIO.setup(23, GPIO.IN)  
+GPIO.setup(24, GPIO.IN)
+
+# Config for display baudrate (default max is 24mhz):
+BAUDRATE = 64000000
+
+# Setup SPI bus using hardware SPI:
+spi = board.SPI()
+
+# Create the ST7789 display:
+disp = st7789.ST7789(
+    spi,
+    cs=cs_pin,
+    dc=dc_pin,
+    rst=reset_pin,
+    baudrate=BAUDRATE,
+    width=135,
+    height=240,
+    x_offset=53,
+    y_offset=40,
+)
+
+# Create blank image for drawing.
+# Make sure to create image with mode 'RGB' for full color.
+height = disp.width  # we swap height/width to rotate it to landscape!
+width = disp.height
+image = Image.new('RGB', (width, height))
+rotation = 90
+
+# Get drawing object to draw on image.
+draw = ImageDraw.Draw(image)
+
+# Draw a black filled box to clear the image.
+draw.rectangle((0, 0, width, height), outline=0, fill=(0, 0, 0))
+disp.image(image, rotation)
+# Draw some shapes.
+# First define some constants to allow easy resizing of shapes.
+padding = -2
+top = padding
+bottom = height - padding
+# Move left to right keeping track of the current x position for drawing shapes.
+x = 0
+
+# Alternatively load a TTF font.  Make sure the .ttf font file is in the
+# same directory as the python script!
+# Some other nice fonts to try: http://www.dafont.com/bitmap.php
+#font = ImageFont.truetype('/usr/share/fonts/truetype/dejavu/DejaVuSansMono-Bold.ttf', 24)
+font_small = font = ImageFont.truetype('/usr/share/fonts/truetype/dejavu/DejaVuSansMono-Bold.ttf', 24)
+font = ImageFont.truetype('/usr/share/fonts/truetype/dejavu/DejaVuSansMono-Bold.ttf', 48)
+
+# Turn on the backlight
+backlight = digitalio.DigitalInOut(board.D22)
+backlight.switch_to_output()
+backlight.value = True
+
+# Watchdog timer for screen on/off control based on button presses
+#    Turns off screen 10s after last button press
+#    Turns on screen for 10s when starting up
+#    Restart fim slideshow when the screen blanks so there is an indicator when it's going to change the selection
+def backlight_callback():
+    global backlight
+    backlight.value = False
+    sysbus = dbus.SystemBus()
+    systemd1 = sysbus.get_object('org.freedesktop.systemd1', '/org/freedesktop/systemd1')
+    manager = dbus.Interface(systemd1, 'org.freedesktop.systemd1.Manager')
+    job = manager.RestartUnit('fim.service', 'fail')
+
+watchdog = Watchdog(10.0, backlight_callback)
+
+# Figure out which albums are present as well as the special 'All' album
+albums = [ 'All' ]
+selected_album = 0
+try:
+    with open('/etc/default/fim_album_index', 'r') as f:
+        selected_album = int(f.readline())
+except IOError:
+    pass
+except ValueError:
+    pass
+for root, dirs, files in walklevel('/tank/pictures'):
+    for folder in dirs:
+        if folder == '.stfolder':
+            continue
+        albums.append(folder)
+albums.sort()
+
+# Method for drawing on the screen
+#    Called by the button handlers since we don't need anything more than a basic while(1) main for this setup
+def refresh_screen():
+    global width, height, x, y, top, draw, selected_album, albums, font, font_small
+
+    # Draw a black filled box to clear the image.
+    draw.rectangle((0, 0, width, height), outline=0, fill=0)
+
+    # Split the line on spaces and then add a blank line if needed to avoid crashes
+    text_lines = albums[selected_album].split(' ')
+    if len(text_lines) < 2:
+        text_lines.append('')
+    
+    # Write some text
+    y = top
+    draw.text((x, y), text_lines[0], font=font, fill='#DCDCDC')
+    y += font.getsize('0')[1]
+    draw.text((x, y), text_lines[1], font=font, fill='#DCDCDC')
+    lux = 'Light: %.2f Lux' % sensor.lux
+    y = height - font_small.getsize(lux)[1]
+    draw.text((x, y), lux, font=font_small, fill='#DCDCDC')
+
+    # Display image.
+    disp.image(image, rotation)
+
+# Write current album when restarting the slideshow
+def write_selected_album():
+    with open('/etc/default/fim_album', 'w') as f:
+        f.write(str(selected_album))
+    with open('/etc/default/fim_album_path', 'w') as f:
+        if not selected_album == 0:
+            f.write('/tank/pictures/' + albums[selected_album])
+        else:
+            f.write('/tank/pictures')
+
+# Interrupt callback for changing albums (up)
+def up_button(channel):
+    global selected_album, albums, backlight
+    backlight.value = True
+    selected_album += 1
+    if selected_album >= len(albums):
+        selected_album = 0
+    refresh_screen()
+    write_selected_album()
+    watchdog.reset()
+    
+# Interrupt callback for changing albums (dn)
+def dn_button(channel):
+    global selected_album, albums, backlight
+    backlight.value = True
+    selected_album -= 1
+    if selected_album < 0:
+        selected_album = len(albums) - 1
+    refresh_screen()
+    write_selected_album()
+    watchdog.reset()
+
+# Setup button interrupts
+GPIO.add_event_detect(23, GPIO.FALLING, callback=up_button, bouncetime=300)
+GPIO.add_event_detect(24, GPIO.FALLING, callback=dn_button, bouncetime=300)
+
+# Draw initial screen state
+refresh_screen()
+
+# Kick off watchdog to start the 10s initial 'on' status
+watchdog.reset()
+
+# Work with the LCD / Buttons in an infinate loop
+while True:
+    time.sleep(300)