#!/usr/bin/env python3
import logging
import math
import pathlib
import random
import sys
import time
import threading

import RPi.GPIO as GPIO
import ST7735
from fonts.ttf import RobotoMedium as UserFont
from PIL import Image, ImageDraw, ImageFont

import yaml
from grow import Piezo
from grow.moisture import Moisture
from grow.pump import Pump


BUTTONS = [5, 6, 16, 24]
LABELS = ["A", "B", "X", "Y"]

DISPLAY_WIDTH = 160
DISPLAY_HEIGHT = 80

COLOR_WHITE = (255, 255, 255)
COLOR_BLUE = (32, 137, 251)
COLOR_GREEN = (100, 255, 124)
COLOR_YELLOW = (254, 219, 82)
COLOR_RED = (254, 82, 82)


# Only the ALPHA channel is used from these images
icon_drop = Image.open("../icons/icon-drop.png")
icon_nodrop = Image.open("../icons/icon-nodrop.png")
icon_rightarrow = Image.open("../icons/icon-rightarrow.png")
icon_snooze = Image.open("../icons/icon-snooze.png")

alarm = False
alarm_enable = True


def icon(image, icon, position, color):
    col = Image.new("RGBA", (20, 20), color=color)
    image.paste(col, position, mask=icon)


class View:
    def __init__(self):
        pass

    def button_a(self):
        return False

    def button_b(self):
        return False

    def button_x(self):
        return False

    def button_y(self):
        return False

    def update(self):
        pass

    def render(self, canvas):
        pass

    def label(self, canvas, position="X", text="", bgcolor=(0, 0, 0), textcolor=(255, 255, 255), margin=4):
        if position not in ["A", "B", "X", "Y"]:
            raise ValueError(f"Invalid label position {position}")

        draw = ImageDraw.Draw(canvas)
        text_w, text_h = draw.textsize(text, font=font)
        text_h = 11
        text_w += margin * 2
        text_h += margin * 2

        if position == "A":
            x, y = 0, 0
        if position == "B":
            x, y = 0, DISPLAY_HEIGHT - text_h
        if position == "X":
            x, y = DISPLAY_WIDTH - text_w, 0
        if position == "Y":
            x, y = DISPLAY_WIDTH - text_w, DISPLAY_HEIGHT - text_h

        x2, y2 = x + text_w, y + text_h

        draw.rectangle((x, y, x2, y2), bgcolor)
        draw.text(
            (x + margin, y + margin - 1),
            text,
            font=font,
            fill=textcolor
        )


class MainView(View):
    def __init__(self, channels=None):
        self.channels = channels
        View.__init__(self)

    def render_channel(self, canvas, channel, font):
        draw = ImageDraw.Draw(image)
        x = [21, 61, 101][channel.channel - 1]

        # Saturation amounts from each sensor
        saturation = channel.sensor.saturation
        active = channel.sensor.active and channel.enabled

        if active:
            # Draw background bars
            draw.rectangle(
                (x, int((1.0 - saturation) * HEIGHT), x + 37, HEIGHT),
                channel.indicator_color(saturation) if active else (229, 229, 229),
            )

        # Channel selection icons
        x += 15
        draw.rectangle(
            (x, 2, x + 15, 17),
            channel.indicator_color(saturation, channel.label_colours) if active else (129, 129, 129),
        )

        # TODO: replace number text with graphic
        tw, th = font.getsize("{}".format(channel.channel))
        draw.text(
            (x + int(math.ceil(8 - (tw / 2.0))), 2),
            "{}".format(channel.channel),
            font=font,
            fill=(255, 255, 255),
        )

    def render(self, canvas):
        draw = ImageDraw.Draw(canvas)
        width, height = canvas.size
        draw.rectangle((0, 0, width, height), (255, 255, 255))

        for channel in self.channels:
            self.render_channel(canvas, channel, font)

        # Icon backdrops
        draw.rectangle((0, 0, 19, 19), (32, 138, 251))

        # Icons
        icon(image, icon_rightarrow, (0, 0), (255, 255, 255))

        alarm.render(canvas, (0, DISPLAY_HEIGHT - 19))


class DetailView(View):
    def __init__(self, channel=None):
        self.channel = channel
        View.__init__(self)

    def render(self, canvas):
        draw = ImageDraw.Draw(canvas)
        width, height = canvas.size
        draw.rectangle((0, 0, width, height), (255, 255, 255))

        draw.text(
            (23, 3),
            "{}".format(self.channel.title),
            font=font,
            fill=(0, 0, 0),
        )

        graph_height = DISPLAY_HEIGHT - 20

        draw.rectangle((
            0, 20,
            DISPLAY_WIDTH, DISPLAY_HEIGHT
        ), (60, 60, 60))

        offset_x = 20
        offset_y = 20

        for x, value in enumerate(self.channel.sensor.history[:DISPLAY_WIDTH]):
            color = self.channel.indicator_color(value)
            h = value * graph_height
            draw.rectangle((x, DISPLAY_HEIGHT - h, x + 1, DISPLAY_HEIGHT), color)

        alarm_line = self.channel.alarm_level * graph_height
        draw.rectangle((0, DISPLAY_HEIGHT - alarm_line, DISPLAY_WIDTH, DISPLAY_HEIGHT - alarm_line + 1), (255, 0, 0))
        draw.rectangle((DISPLAY_WIDTH - 50, DISPLAY_HEIGHT - alarm_line - 16, DISPLAY_WIDTH, DISPLAY_HEIGHT - alarm_line + 1), (255, 0, 0))

        draw.text(
            (DISPLAY_WIDTH - 47, DISPLAY_HEIGHT - alarm_line - 15),
            "Alarm",
            font=font,
            fill=(255, 255, 255),
        )

        # Icon backdrops
        draw.rectangle((0, 0, 19, 19), (32, 138, 251))

        # Icons
        icon(image, icon_rightarrow, (0, 0), (255, 255, 255))

        # Edit
        self.label(canvas, "X", "Edit", textcolor=(255, 255, 255), bgcolor=COLOR_RED)


class EditView(View):
    def __init__(self, channel=None):
        self._options = [
                {"title": "Alarm Level", "prop": "alarm_level", "inc": 0.05, "min": 0, "max": 1.0, "scale": 100, "format": "{value:0.2f}%"},
                {"title": "Wet Point", "prop": "wet_point", "inc": 0.5, "min": 1, "max": 27, "scale": 1, "format": "{value:0.2f}Hz"},
                {"title": "Dry Point", "prop": "dry_point", "inc": 0.5, "min": 1, "max": 27, "scale": 1,  "format": "{value:0.2f}Hz"},
        ]
        self._current_option = 0
        self._change_mode = False
        self.channel = channel
        View.__init__(self)

    def render(self, canvas):
        draw = ImageDraw.Draw(canvas)
        width, height = canvas.size
        draw.rectangle((0, 0, width, height), (255, 255, 255))

        draw.text(
            (23, 3),
            "{}".format(self.channel.title),
            font=font,
            fill=(0, 0, 0)
        )


        draw.text(
            (5, 25),
            f"Now: {self.channel.sensor.saturation * 100:.2f}% {self.channel.sensor.moisture:.2f}Hz",
            font=font,
            fill=(0, 0, 0)
        )

        option = self._options[self._current_option]
        title = option["title"]
        prop = option["prop"]
        value = getattr(self.channel, prop)
        scale = option["scale"]
        text = option["format"].format(value=value * scale)
        draw.text(
            (5, 40),
            f"{title} : {text}",
            font=font,
            fill=(0, 0, 0)
        )

        draw.rectangle((0, 0, 19, 19), (138, 138, 138))

        # Icons
        icon(image, icon_rightarrow, (0, 0), (255, 255, 255))


        if self._change_mode:
            self.label(canvas, "Y", "++", textcolor=COLOR_WHITE, bgcolor=COLOR_YELLOW)
            self.label(canvas, "B", "--", textcolor=COLOR_WHITE, bgcolor=COLOR_BLUE)
        else:
            self.label(canvas, "Y", "Change", textcolor=COLOR_WHITE, bgcolor=COLOR_YELLOW)
            self.label(canvas, "B", "Next", textcolor=COLOR_WHITE, bgcolor=COLOR_BLUE)

        self.label(canvas, "X", "Done", textcolor=COLOR_WHITE, bgcolor=COLOR_RED)

    def button_a(self):
        pass

    def button_b(self):
        if self._change_mode:
            option = self._options[self._current_option]
            prop = option["prop"]
            inc = option["inc"]
            limit = option["min"]
            value = getattr(self.channel, prop)
            value -= inc
            if value < limit:
                value = limit
            setattr(self.channel, prop, value)
        else:
            self._current_option += 1
            self._current_option %= len(self._options)

    def button_x(self):
        if self._change_mode:
            self._change_mode = False
            return True
        return False

    def button_y(self):
        if self._change_mode:
            option = self._options[self._current_option]
            prop = option["prop"]
            inc = option["inc"]
            limit = option["max"]
            value = getattr(self.channel, prop)
            value += inc
            if value > limit:
                value = limit
            setattr(self.channel, prop, value)
        else:
            self._change_mode = True


class Channel:
    bar_colours = [
        (192, 225, 254),  # Blue
        (196, 255, 209),  # Green
        (255, 243, 192),  # Yellow
        (254, 192, 192),  # Red
    ]

    label_colours = [
        COLOR_BLUE,
        COLOR_GREEN,
        COLOR_YELLOW,
        COLOR_RED,
    ]

    def __init__(
        self,
        display_channel,
        sensor_channel,
        pump_channel,
        title=None,
        water_level=0.5,
        alarm_level=0.5,
        pump_speed=0.7,
        pump_time=0.7,
        watering_delay=30,
        wet_point=0.7,
        dry_point=26.7,
        icon=None,
        auto_water=False,
        enabled=False,
    ):
        self.channel = display_channel
        self.sensor = Moisture(sensor_channel)
        self.pump = Pump(pump_channel)
        self.water_level = water_level
        self.alarm_level = alarm_level
        self.auto_water = auto_water
        self.pump_speed = pump_speed
        self.pump_time = pump_time
        self.watering_delay = watering_delay
        self.wet_point = wet_point
        self.dry_point = dry_point
        self.last_dose = time.time()
        self.icon = icon
        self.enabled = enabled
        self.alarm = False
        self.title = "Channel {}".format(display_channel) if title is None else title

        self.sensor.set_wet_point(wet_point)
        self.sensor.set_dry_point(dry_point)

    def indicator_color(self, value, r=None):
        value = 1.0 - value

        if r is None:
            r = self.bar_colours
        if value == 1.0:
            return r[-1]
        if value == 0.0:
            return r[0]

        value *= len(r) - 1
        a = int(math.floor(value))
        b = a + 1
        blend = float(value - a)

        r, g, b = [int(((r[b][i] - r[a][i]) * blend) + r[a][i]) for i in range(3)]

        return (r, g, b)

    def update_from_yml(self, config):
        if config is not None:
            self.pump_speed = config.get("pump_speed", self.pump_speed)
            self.pump_time = config.get("pump_time", self.pump_time)
            self.alarm_level = config.get("alarm_level", self.alarm_level)
            self.water_level = config.get("water_level", self.water_level)
            self.watering_delay = config.get("watering_delay", self.watering_delay)
            self.auto_water = config.get("auto_water", self.auto_water)
            self.enabled = config.get("enabled", self.enabled)
            self.wet_point = config.get("wet_point", self.wet_point)
            self.dry_point = config.get("dry_point", self.dry_point)

        pass

    def __str__(self):
        return """Channel: {channel}
Enabled: {enabled}
Alarm level: {alarm_level}
Auto water: {auto_water}
Water level: {water_level}
Pump speed: {pump_speed}
Pump time: {pump_time}
Delay: {watering_delay}
Wet point: {wet_point}
Dry point: {dry_point}
""".format(
            **self.__dict__
        )

    def water(self):
        if not self.auto_water:
            return False
        if time.time() - self.last_dose > self.watering_delay:
            self.pump.dose(self.pump_speed, self.pump_time, blocking=False)
            self.last_dose = time.time()
            return True
        return False

    def render(self, image, font):
        pass

    def update(self):
        if not self.enabled:
            return
        sat = self.sensor.saturation
        if sat < self.water_level:
            if self.water():
                logging.info(
                    "Watering Channel: {} - rate {:.2f} for {:.2f}sec".format(
                        self.channel, self.pump_speed, self.pump_time
                    )
                )
            if sat < self.alarm_level and not self.alarm:
                logging.warning(
                    "Alarm on Channel: {} - saturation is {:.2f}% (warn level {:.2f}%)".format(
                        self.channel, sat * 100, self.alarm_level * 100
                    )
                )
                self.alarm = True


class Alarm:
    def __init__(self, enabled=True, interval=10.0, beep_frequency=440):
        self.piezo = Piezo()
        self.enabled = enabled
        self.interval = interval
        self.beep_frequency = beep_frequency
        self._triggered = False
        self._time_last_beep = time.time()
        self._sleep_until = None

    def update_from_yml(self, config):
        if config is not None:
            self.enabled = config.get("alarm_enable", self.enabled)
            self.interval = config.get("alarm_interval", self.interval)

    def update(self):
        if self._sleep_until is not None:
            if self._sleep_until > time.time():
                return

        if self.enabled and self._triggered and time.time() - self._time_last_beep > self.interval:
            self.piezo.beep(self.beep_frequency, 0.1, blocking=False)
            threading.Timer(0.3, self.piezo.beep, args=[self.beep_frequency, 0.1], kwargs={"blocking":False}).start()
            threading.Timer(0.6, self.piezo.beep, args=[self.beep_frequency, 0.1], kwargs={"blocking":False}).start()
            self._time_last_beep = time.time()

    def render(self, canvas, position=(0, 0)):
        draw = ImageDraw.Draw(canvas)
        x, y = position
        # Draw the snooze icon- will be pulsing red if the alarm state is True
        draw.rectangle((x, y, x + 19, y + 19), (255, 255, 255))
        r = 129
        if self._triggered:
            r = int(((math.sin(time.time() * 3 * math.pi) + 1.0) / 2.0) * 255)
        icon(image, icon_snooze, (x, y - 1), (r, 129, 129))

        if self._sleep_until is not None:  # TODO maybe sleeping alarm icon?
            if self._sleep_until > time.time():
                draw.text((x, y), "zZ", font=font, fill=(255, 255, 255))

    def trigger(self):
        self._triggered = True

    def disable(self):
        self.enabled = False

    def enable(self):
        self.enabled = True

    def sleep(self, duration=500):
        self._sleep_until = time.time() + duration


class ViewController():
    def __init__(self, views):
        self.views = views
        self._current_view = 0
        self._current_subview = 0

    def next_subview(self):
        view = self.views[self._current_view]
        if isinstance(view, tuple):
            self._current_subview += 1
            self._current_subview %= len(view)

    def next_view(self):
        if self._current_subview == 0:
            self._current_view += 1
            self._current_view %= len(self.views)
            self._current_subview = 0
            print(f"Switched to view {self._current_view}")

    def get_current_view(self):
        view = self.views[self._current_view]
        if isinstance(view, tuple):
            view = view[self._current_subview]

        return view

    @property
    def view(self):
        return self.get_current_view()

    def update(self):
        self.view.update()

    def render(self, canvas):
        self.view.render(canvas)

    def button_a(self):
        if not self.view.button_a():
            self.next_view()

    def button_b(self):
        self.view.button_b()

    def button_x(self):
        if not self.view.button_x():
            self.next_subview()

    def button_y(self):
        self.view.button_y()


def handle_button(pin):
    index = BUTTONS.index(pin)
    label = LABELS[index]

    if label == "A":  # Select View
        viewcontroller.button_a()
 
    if label == "B":  # Sleep Alarm
        if not viewcontroller.button_b():
            alarm.sleep()

    if label == "X":
        viewcontroller.button_x()

    if label == "Y":
        viewcontroller.button_y()


# Set up the ST7735 SPI Display
display = ST7735.ST7735(
    port=0, cs=1, dc=9, backlight=12, rotation=270, spi_speed_hz=80000000
)
display.begin()
WIDTH, HEIGHT = display.width, display.height

# Set up our canvas and prepare for drawing
image = Image.new("RGBA", (WIDTH, HEIGHT), color=(255, 255, 255))
font = ImageFont.truetype(UserFont, 14)


# Pick a random selection of plant icons to display on screen
channels = [
    Channel(1, 1, 1),
    Channel(2, 2, 2),
    Channel(3, 3, 3),
]

viewcontroller = ViewController([
    MainView(channels=channels),
    (DetailView(channel=channels[0]), EditView(channel=channels[0])),
    (DetailView(channel=channels[1]), EditView(channel=channels[1])),
    (DetailView(channel=channels[2]), EditView(channel=channels[2]))
])

alarm = Alarm()


def main():
    global alarm

    GPIO.setmode(GPIO.BCM)
    GPIO.setwarnings(False)
    GPIO.setup(BUTTONS, GPIO.IN, pull_up_down=GPIO.PUD_UP)

    for pin in BUTTONS:
        GPIO.add_event_detect(pin, GPIO.FALLING, handle_button, bouncetime=200)

    settings_file = "settings.yml"
    if len(sys.argv) > 1:
        settings_file = sys.argv[1]
    settings_file = pathlib.Path(settings_file)
    if settings_file.is_file():
        try:
            config = yaml.safe_load(open(settings_file))
        except yaml.parser.ParserError as e:
            raise yaml.parser.ParserError(
                "Error parsing settings file: {} ({})".format(settings_file, e)
            )

        for channel in channels:
            ch = config.get("channel{}".format(channel.channel), None)
            channel.update_from_yml(ch)

        settings = config.get("general", None)
        if settings is not None:
            alarm.update_from_yml(settings)

    print("Channels:")
    for channel in channels:
        print(channel)

    print(
        """Settings:
Alarm Enabled: {}
Alarm Interval: {:.2f}s
""".format(
            alarm.enabled, alarm.interval
        )
    )

    while True:
        for channel in channels:
            channel.update()
            if channel.alarm:
                alarm.trigger()

        alarm.update()

        viewcontroller.update()
        viewcontroller.render(image)
        display.display(image.convert("RGB"))

        # 5 FPS
        time.sleep(1.0 / 10)


if __name__ == "__main__":
    main()