brewpi/client/brewpi_gui.py

#!/usr/bin/env python3
from main_window import Ui_MainWindow
from PyQt5 import QtWidgets, QtGui, QtCore
import json
import sys
import threading
import time
from pathlib import Path
import matplotlib
matplotlib.use("Qt5Agg")
from matplotlib.backends.backend_qt5agg import FigureCanvasQTAgg
from matplotlib.figure import Figure
from matplotlib.ticker import AutoMinorLocator
from components.sud import Sud
from ws.client.ws_client import WsClient
from ws.message import MessageDispatcherSync
from queue import Queue
import asyncio
from user_config import UserConfig

# str(SudState.X) values (as sent in the 'State' message) that count as
# "running" for enabling/disabling the Start/Pause/Stop toolbar actions.
SUD_RUNNING_STATES = {"SudState.RAMPING", "SudState.HOLDING", "SudState.WAIT_USER"}
SUD_HOLDING_STATE = "SudState.HOLDING"
SUD_WAIT_USER_STATE = "SudState.WAIT_USER"
SUD_PAUSED_STATE = "SudState.PAUSED"


def _style_axis(ax):
	ax.set_facecolor('white')
	ax.spines['top'].set_visible(False)
	ax.spines['right'].set_visible(False)
	ax.xaxis.set_minor_locator(AutoMinorLocator())
	ax.yaxis.set_minor_locator(AutoMinorLocator())
	ax.tick_params(which='major', direction='out', labelsize='small')
	ax.tick_params(which='minor', direction='out', length=2)
	ax.grid(which='major', linestyle='-', linewidth=0.5, alpha=0.3)
	ax.grid(which='minor', linestyle=':', linewidth=0.5, alpha=0.15)


class RealtimePlot(FigureCanvasQTAgg):
	"""Live theta/heatrate/heater-power strip charts, mirroring figure 1 of
	scripts/demos/sud/demo_sud.py but fed from the websocket connection
	instead of an offline simulation run."""

	def __init__(self):
		figure = Figure(facecolor='white')
		FigureCanvasQTAgg.__init__(self, figure)

		self.ax_temp, self.ax_rate, self.ax_power = figure.subplots(3, 1, sharex=True)

		self.line_temp_ist, = self.ax_temp.plot([], [], '-b', linewidth=1, label="theta_ist")
		self.line_temp_soll, = self.ax_temp.plot([], [], '-r', linewidth=1, label="theta_soll")
		self.ax_temp.set_ylabel("Temp [°C]")
		self.ax_temp.legend(loc='upper left', fontsize='small')

		self.line_rate_ist, = self.ax_rate.plot([], [], '-b', linewidth=1, label="heatrate_ist")
		self.line_rate_soll, = self.ax_rate.plot([], [], '-r', linewidth=1, label="heatrate_soll")
		self.ax_rate.set_ylabel("Rate [K/min]")
		self.ax_rate.legend(loc='upper left', fontsize='small')

		self.line_power_set, = self.ax_power.plot([], [], '-r', linewidth=1, label="power_set")
		self.line_power_eff, = self.ax_power.plot([], [], '-b', linewidth=1, label="power_eff")
		self.ax_power.set_ylabel("Power [W]")
		self.ax_power.set_xlabel("t [s]")
		self.ax_power.legend(loc='upper left', fontsize='small')

		for ax in (self.ax_temp, self.ax_rate, self.ax_power):
			_style_axis(ax)

		# Only the bottom subplot needs x tick labels - sharex keeps the
		# others in sync without repeating them.
		self.ax_temp.label_outer()
		self.ax_rate.label_outer()

		figure.tight_layout()
		self.reset()

	def reset(self):
		self.t0 = time.monotonic()
		self.t = []
		self.temp_ist = []
		self.temp_soll = []
		self.rate_ist = []
		self.rate_soll = []
		self.power_set = []
		self.power_eff = []

	def sample(self, temp_ist, temp_soll, rate_ist, rate_soll, power_set, power_eff):
		self.t.append(time.monotonic() - self.t0)
		self.temp_ist.append(temp_ist)
		self.temp_soll.append(temp_soll)
		self.rate_ist.append(rate_ist)
		self.rate_soll.append(rate_soll)
		self.power_set.append(power_set)
		self.power_eff.append(power_eff)

		self.line_temp_ist.set_data(self.t, self.temp_ist)
		self.line_temp_soll.set_data(self.t, self.temp_soll)
		self.line_rate_ist.set_data(self.t, self.rate_ist)
		self.line_rate_soll.set_data(self.t, self.rate_soll)
		self.line_power_set.set_data(self.t, self.power_set)
		self.line_power_eff.set_data(self.t, self.power_eff)

		for ax in (self.ax_temp, self.ax_rate, self.ax_power):
			ax.relim()
			ax.autoscale_view()

		self.draw_idle()


class SudForecastPlot(FigureCanvasQTAgg):
	"""A preview of a Sud schedule's temperature course, computed from its
	nominal ramp rates/hold durations alone (no plant/controller model -
	just how long the declared schedule says each step should take), so it
	can be shown as soon as a schedule is loaded/edited, before a brew is
	actually started (show_schedule()).

	Once running, nonideal ramp rates/user pauses make that static estimate
	drift from reality - show_dynamic() instead re-anchors the projection
	every tick: the already-elapsed part is the actual measured trace
	(line, solid), and only the remaining steps are projected forward from
	the live current temperature/step/hold_remaining (line_projected,
	dashed)."""

	def __init__(self):
		figure = Figure(facecolor='white')
		FigureCanvasQTAgg.__init__(self, figure)

		self.ax = figure.subplots(1, 1)
		self.line, = self.ax.plot([], [], '-b', linewidth=1.5, zorder=2)
		self.line_projected, = self.ax.plot([], [], '--b', linewidth=1.5, alpha=0.5, zorder=2)
		self.progress_line = self.ax.axvline(0, color='g', linewidth=1.5, visible=False, zorder=2)
		# Current temperature - drawn behind (lower zorder than) the
		# forecast/progress lines so it never covers them.
		self.current_temp_line = self.ax.axhline(0, color='r', linewidth=1.5, visible=False, zorder=1)
		self.ax.set_xlabel("t [min]")
		self.ax.set_ylabel("Temp [°C]")
		_style_axis(self.ax)

		figure.tight_layout()

	@staticmethod
	def _estimate_course(schedule, start_theta):
		"""Walks the schedule, accumulating (t, theta) waypoints: ramps take
		abs(delta)/rate minutes at the declared rate, holds last for their
		duration at the temperature the preceding ramp reached. A step may
		carry both - ramp then hold - contributing both segments in turn."""
		t = [0.0]
		theta = [start_theta]
		for step in schedule:
			ramp = step.get('ramp')
			hold = step.get('hold')
			target = step.get('temperature')
			if ramp is not None and target is not None:
				rate = ramp.get('rate', 0)
				if rate > 0:
					t.append(t[-1] + abs(target - theta[-1]) / rate * 60.0)
					theta.append(target)
			if hold is not None:
				t.append(t[-1] + hold.get('duration', 0) * 60.0)
				theta.append(theta[-1])
		return t, theta

	def show_schedule(self, schedule, start_theta, name):
		"""Quick, approximate preview shown immediately when a schedule is
		loaded - assumes every ramp instantly achieves/sustains its
		declared rate, which real plants/controllers don't. Superseded by
		show_precomputed_course() shortly after, once the server's
		simulation-based forecast (components/sud_forecast.py) arrives."""
		t, theta = self._estimate_course(schedule, start_theta)
		t_min = [seconds / 60.0 for seconds in t]
		self._show_static_course(t_min, theta, name)

	def show_precomputed_course(self, t_min, theta, name):
		"""Like show_schedule(), but (t_min, theta) were already computed
		by the server simulating the schedule with its real plant/
		controller - see Window.on_sud_forecast_received()."""
		self._show_static_course(t_min, theta, name)

	def _show_static_course(self, t_min, theta, name):
		self.line.set_data(t_min, theta)
		self.line_projected.set_data([], [])
		self.ax.relim()
		self.ax.autoscale_view()
		self.ax.set_title("{} - {:.0f} min total".format(name, t_min[-1] if t_min else 0.0), fontsize='small')
		self.figure.tight_layout()
		self.draw_idle()

	def show_dynamic(self, history, t_rem_min, theta_rem, name):
		"""Re-anchored forecast for a run in progress: history is the
		[(t_min, theta), ...] actually measured so far (drawn solid);
		t_rem_min/theta_rem is the projected remainder (dashed), already
		computed by the caller - either the server's simulation-based
		SudForecastEstimator (preferred, see Window.on_plot_timer()) or,
		until that arrives, a quick naive abs(delta)/rate fallback."""
		hist_t = [t for t, _ in history]
		hist_theta = [theta for _, theta in history]
		self.line.set_data(hist_t, hist_theta)
		self.line_projected.set_data(t_rem_min, theta_rem)

		self.ax.relim()
		self.ax.autoscale_view()
		total_min = t_rem_min[-1] if t_rem_min else (hist_t[-1] if hist_t else 0.0)
		self.ax.set_title("{} - {:.0f} min total (est.)".format(name, total_min), fontsize='small')
		self.figure.tight_layout()
		self.draw_idle()

	def show_no_schedule(self):
		self.line.set_data([], [])
		self.line_projected.set_data([], [])
		self.clear_progress()
		self.ax.relim()
		self.ax.autoscale_view()
		self.ax.set_title("No sud loaded", fontsize='small')
		self.figure.tight_layout()
		self.draw_idle()

	def set_progress(self, t_min):
		self.progress_line.set_xdata([t_min, t_min])
		self.progress_line.set_visible(True)
		self.draw_idle()

	def clear_progress(self):
		self.progress_line.set_visible(False)
		self.draw_idle()

	def set_current_temp(self, theta):
		self.current_temp_line.set_ydata([theta, theta])
		self.current_temp_line.set_visible(True)
		self.draw_idle()

	def clear_current_temp(self):
		self.current_temp_line.set_visible(False)
		self.draw_idle()


class Window(QtWidgets.QMainWindow, Ui_MainWindow):
	# on_*_changed()/on_ws_connect_changed() are invoked straight from the
	# websocket client's background thread (WsClient.bg_thread), but Qt
	# widgets may only be touched from the GUI thread. A signal/slot crosses
	# that boundary safely (Qt auto-queues the slot call onto the receiver's
	# thread when sender and receiver differ) - recv_signal carries the
	# handler itself plus its one argument, so every channel can share it
	# instead of needing one signal per handler.
	recv_signal = QtCore.pyqtSignal(object, object)

	def __init__(self):
		QtWidgets.QMainWindow.__init__(self)
		self.setWindowIcon(QtGui.QIcon('res/beer.png'))
		self.recv_signal.connect(self._dispatch_recv)
		self.user_config = UserConfig()

		loop = asyncio.new_event_loop()
		asyncio.set_event_loop(loop)
		self.msg_dispatch = MessageDispatcherSync(auto_subscribe=True)
		self.msg_dispatch.on_connect_changed = lambda connected: self.recv_signal.emit(self.on_ws_connect_changed, connected)
		self.ws_client = WsClient(listener=self.msg_dispatch, loop=loop)
		self.connected = False
		self.sud_loaded = False
		# Whether the loaded schedule has zero steps (e.g. just after "New
		# Sud") - distinct from sud_loaded, which just means a Sud is
		# configured server-side at all. Defaults True so Start/Pause/Stop
		# stay disabled until a non-empty schedule is actually confirmed.
		self.sud_empty = True
		self.sud_state = None
		self.sud_user_message = None
		# Mirrors the server's TempController.enabled - gates the
		# temp/heatrate setpoint controls (see on_tempctrl_changed()).
		self.tc_enabled = False
		# Global, not Sud-specific - from the 'System' channel's one-time
		# startup message. warp_factor defaults to 1.0 (no scaling) until
		# that arrives, or for a server that doesn't send it at all.
		self.ambient_temp = None
		self.warp_factor = 1.0
		# Elapsed simulated seconds of the current run, as reported by the
		# server (Sud's own tick-counted 'elapsed' - see components/sud.py) -
		# None while not running. Used to position the forecast plot's
		# progress line; ground truth, not reconstructed from wall-clock
		# time, since the server's actual achieved speedup runs measurably
		# below its nominal configured warp factor under real scheduling
		# load, which used to make the live trace visibly drift from the
		# forecast.
		self.sud_elapsed_seconds = None
		# Resolved schedule + live progress within it, kept around so the
		# forecast plot can be dynamically re-anchored every tick instead of
		# only estimated once when the schedule was (re)loaded - see
		# refresh_forecast()/SudForecastPlot.show_dynamic().
		self.sud_name = ''
		self.sud_schedule = []
		self.sud_step_index = None
		self.sud_step_descr = None
		self.sud_step_type = None
		self.sud_hold_remaining = 0.0
		# [(t_min, theta), ...] actually measured since the current run
		# started - the "already happened" part of the dynamic forecast.
		self.forecast_history = []
		# (anchor_min, T, Theta) from the server's simulation-based estimate
		# of the remaining steps, recomputed on every step change -
		# anchor_min is elapsed_min as of receipt, so on_plot_timer() can
		# re-anchor the projection without it drifting right every tick.
		# None until it arrives (or after a step change, until the next one
		# does), in which case on_plot_timer() falls back to the naive
		# estimate.
		self.server_remaining_forecast = None
		self.msg_pot = self.msg_dispatch.msgio_get('Pot')
		self.msg_sensor = self.msg_dispatch.msgio_get('Sensor')
		self.msg_heater = self.msg_dispatch.msgio_get('Heater')
		self.msg_stirrer = self.msg_dispatch.msgio_get('Stirrer')
		self.msg_tempctrl = self.msg_dispatch.msgio_get('TempCtrl')
		self.msg_sud = self.msg_dispatch.msgio_get('Sud')
		self.msg_system = self.msg_dispatch.msgio_get('System')

		# set_recv_handler's callback runs on WsClient's background thread -
		# route each through recv_signal instead of wiring the real handler
		# directly, so its body always runs on the GUI thread.
		self.msg_pot.set_recv_handler(lambda msg: self.recv_signal.emit(self.on_pot_changed, msg))
		self.msg_sensor.set_recv_handler(lambda msg: self.recv_signal.emit(self.on_sensor_changed, msg))
		self.msg_heater.set_recv_handler(lambda msg: self.recv_signal.emit(self.on_heater_changed, msg))
		self.msg_stirrer.set_recv_handler(lambda msg: self.recv_signal.emit(self.on_stirrer_changed, msg))
		self.msg_tempctrl.set_recv_handler(lambda msg: self.recv_signal.emit(self.on_tempctrl_changed, msg))
		self.msg_sud.set_recv_handler(lambda msg: self.recv_signal.emit(self.on_sud_changed, msg))
		self.msg_system.set_recv_handler(lambda msg: self.recv_signal.emit(self.on_system_changed, msg))

		self.setupUi(self)
		# Matches tc_enabled's default (False) until the server says otherwise.
		self.Slider_temp_soll.setEnabled(False)
		self.doubleSpinBox_heatrate_soll.setEnabled(False)
		# Permanent (right-aligned, not cleared by showMessage()/clearMessage())
		# label for static environment info - distinct from the status bar's
		# transient step/schedule messages.
		self.status_label_env = QtWidgets.QLabel()
		self.statusBar().addPermanentWidget(self.status_label_env)
		self.update_status_env_label()

		# Blinking indicator for the temperature controller's own COOL
		# state (target below the current temperature - the heater is
		# forced off server-side and we just wait for ambient loss to
		# catch up).
		self.tc_cooling = False
		self.status_label_cooling = QtWidgets.QLabel("Cool down")
		self.status_label_cooling.setStyleSheet("color: blue; font-weight: bold;")
		self.status_label_cooling.setVisible(False)
		self.statusBar().addPermanentWidget(self.status_label_cooling)
		self.cooling_blink_timer = QtCore.QTimer(self)
		self.cooling_blink_timer.timeout.connect(self.on_cooling_blink)

		self.update_sud_actions()
		self.btn_connect.clicked.connect(self.on_btn_connect_clicked)
		self.actionStart.triggered.connect(self.on_action_sud_start)
		self.actionPause.triggered.connect(self.on_action_sud_pause)
		self.actionStop.triggered.connect(self.on_action_sud_stop)
		self.actionSudNew.triggered.connect(self.on_action_sud_new)
		self.actionSudSave.triggered.connect(self.on_action_sud_save)
		self.actionSudLoad.triggered.connect(self.on_action_sud_load)
		self.Slider_pwr_soll.valueChanged.connect(self.on_slider_pwr_soll_changed)
		self.Slider_temp_soll.valueChanged.connect(self.on_slider_temp_soll_changed)
		self.Slider_speed_soll.valueChanged.connect(self.on_slider_stirrer_speed_soll_changed)

		self.doubleSpinBox_heatrate_soll.valueChanged.connect(self.on_heatrate_soll_changed)

		self.checkbox_heater_activate.stateChanged.connect(self.on_checkbox_changed)
		self.checkbox_stirrer_activate.stateChanged.connect(self.on_checkbox_stirrer_activate_changed)
		self.checkbox_tc_enable.stateChanged.connect(self.on_checkbox_tc_enable_changed)
		self.lineEdit_ambient.returnPressed.connect(self.on_ambient_entry_changed)
		self.btn_pot_reset.clicked.connect(self.on_action_pot_reset)
		# Only meaningful (and only shown) once the server confirms its Pot
		# is simulated - see on_system_changed()'s "PlantSim" handling.
		self.btn_pot_reset.setVisible(False)

		self.send_data = Queue()
		self.slider_pwr_initial_update = True
		self.slider_temp_soll_initial_update = True
		self.slider_speed_initial_update = True
		self.checkbox_heater_activate_initial_update = True
		self.checkbox_stirrer_activate_initial_update = True
		self.heatrate_soll_initial_update = True
		self.sud_save_path = None

		# Latest values sampled by the plot timer - written from the
		# websocket recv thread, read from the GUI thread; plain floats so
		# no locking, consistent with how the rest of the GUI is wired.
		self.plot_temp_ist = 0.0
		self.plot_temp_soll = 0.0
		self.plot_rate_ist = 0.0
		self.plot_rate_soll = 0.0
		self.plot_power_set = 0.0
		self.plot_power_eff = 0.0

		self.plot = RealtimePlot()
		plot_layout = QtWidgets.QVBoxLayout(self.widget_plot)
		plot_layout.setContentsMargins(0, 0, 0, 0)
		plot_layout.addWidget(self.plot)

		self.plot_timer = QtCore.QTimer(self)
		self.plot_timer.timeout.connect(self.on_plot_timer)
		self.plot_timer.start(1000)

		self.forecast_plot = SudForecastPlot()
		forecast_layout = QtWidgets.QVBoxLayout(self.widget_plot_forecast)
		forecast_layout.setContentsMargins(0, 0, 0, 0)
		forecast_layout.addWidget(self.forecast_plot)

	def _dispatch_recv(self, handler, msg):
		"""recv_signal's slot - runs on the GUI thread regardless of which
		thread emitted the signal, so handler(msg) can touch Qt widgets
		safely."""
		handler(msg)

	def connect(self):
		self.slider_pwr_initial_update = True
		self.slider_temp_soll_initial_update = True
		self.slider_speed_initial_update = True
		self.checkbox_heater_activate_initial_update = True
		self.checkbox_stirrer_activate_initial_update = True
		self.heatrate_soll_initial_update = True
		self.plot.reset()
		self.ws_client.connect(uri=self.plainTextUri.toPlainText())
		# Fetch the schedule for the Automatic tab's forecast preview - not
		# a user-initiated save, so sud_save_path stays None and
		# on_sud_changed() routes the reply to update_sud_forecast() instead
		# of a save dialog.
		self.msg_sud.send({'Save': True})
		# Re-apply the last ambient temperature we set, in case the server
		# restarted since (and so fell back to its own config.json default).
		remembered_ambient = self.user_config.get('ambient_temperature')
		if remembered_ambient is not None:
			self.msg_system.send({'AmbientTemp': remembered_ambient})

	def _elapsed_min(self):
		"""Simulated-schedule minutes elapsed since the run started, or
		None if no run is in progress - straight from the server's own
		tick-counted Sud.elapsed (see on_sud_changed()'s 'Elapsed'
		handling), already frozen while PAUSED there."""
		if self.sud_elapsed_seconds is None:
			return None
		return self.sud_elapsed_seconds / 60.0

	def on_plot_timer(self):
		self.plot.sample(
			self.plot_temp_ist, self.plot_temp_soll,
			self.plot_rate_ist, self.plot_rate_soll,
			self.plot_power_set, self.plot_power_eff)

		elapsed_min = self._elapsed_min()
		if elapsed_min is not None:
			self.forecast_plot.set_progress(elapsed_min)

			# Re-anchor the forecast from the live state instead of redrawing
			# the static, increasingly-stale estimate from t=0. Frozen while
			# PAUSED (elapsed_min isn't advancing either, and the paused
			# phase - ramp or hold - isn't visible to the client to resume
			# the projection from correctly) - just leave the last draw up.
			if self.sud_state != SUD_PAUSED_STATE and self.plot_temp_ist:
				self.forecast_history.append((elapsed_min, self.plot_temp_ist))
				if self.server_remaining_forecast is not None:
					# Anchored to elapsed_min as of when the server computed
					# this forecast, not the current tick's - it's only
					# recomputed on step changes, so re-adding the live,
					# ever-growing elapsed_min here would push the whole
					# projection further right every tick until the next
					# step change, instead of holding it fixed.
					anchor_min, t_rem, theta_rem = self.server_remaining_forecast
				else:
					# Server's simulation-based remainder hasn't arrived
					# yet (it's recomputed on every step change, off the
					# event loop) - fall back to the quick naive estimate
					# for this one tick.
					anchor_min = elapsed_min
					t_rem, theta_rem = self.forecast_plot._estimate_course(self._remaining_schedule(), self.plot_temp_ist)
				t_rem_min = [anchor_min + seconds / 60.0 for seconds in t_rem]
				self.forecast_plot.show_dynamic(self.forecast_history, t_rem_min, theta_rem, self.sud_name)
		else:
			self.forecast_plot.clear_progress()

		if self.plot_temp_ist:
			self.forecast_plot.set_current_temp(self.plot_temp_ist)
		else:
			self.forecast_plot.clear_current_temp()

	def _remaining_schedule(self):
		"""The not-yet-done part of sud_schedule, for SudForecastPlot's
		dynamic re-anchoring: the current step's already-finished phase is
		dropped, and its still-to-run phase is left for _estimate_course()
		to size from the live theta_now/hold_remaining it's seeded with,
		rather than the step's nominal start."""
		schedule = self.sud_schedule
		index = self.sud_step_index
		if not schedule or index is None or not (0 <= index < len(schedule)):
			return []
		current = schedule[index]
		rest = schedule[index + 1:]
		if self.sud_state == SUD_WAIT_USER_STATE:
			# The current step (both its ramp and hold, if any) is already
			# done - only waiting on the user to advance.
			return rest
		if self.sud_state == SUD_HOLDING_STATE:
			remaining_minutes = max(self.sud_hold_remaining, 0.0) / 60.0
			return [{'hold': {'duration': remaining_minutes}}] + rest
		# RAMPING: _estimate_course() recomputes the ramp's remaining
		# distance from whatever start_theta it's given, so the step is
		# used as-is; its hold phase (if any) hasn't started yet either.
		return [current] + rest

	def disconnect(self):
		# ws_client.disconnect() blocks until the websocket's close handshake
		# completes (or times out, ~10s if the server doesn't ack promptly),
		# joining the connection's background thread - run it off a throwaway
		# thread so that wait doesn't freeze the GUI. on_ws_connect_changed()
		# still flips the button once the disconnect actually finishes.
		threading.Thread(target=self.ws_client.disconnect, daemon=True).start()

	def on_btn_connect_clicked(self):
		if self.connected:
			self.disconnect()
		else:
			self.connect()

	def on_ws_connect_changed(self, connected):
		self.connected = connected
		self.btn_connect.setText("Disconnect" if connected else "Connect")
		if not connected:
			# Nothing reported over a dead connection can be trusted anymore.
			self.sud_loaded = False
			self.sud_empty = True
			self.sud_state = None
			self.sud_user_message = None
			self.tc_enabled = False
			self.checkbox_tc_enable.blockSignals(True)
			self.checkbox_tc_enable.setChecked(False)
			self.checkbox_tc_enable.blockSignals(False)
			self.Slider_temp_soll.setEnabled(False)
			self.doubleSpinBox_heatrate_soll.setEnabled(False)
			self.ambient_temp = None
			self.lineEdit_ambient.clear()
			self.btn_pot_reset.setVisible(False)
			self.warp_factor = 1.0
			self.sud_elapsed_seconds = None
			self.sud_name = ''
			self.sud_schedule = []
			self.sud_step_index = None
			self.sud_step_descr = None
			self.sud_step_type = None
			self.sud_hold_remaining = 0.0
			self.forecast_history = []
			self.server_remaining_forecast = None
			self.set_tc_cooling(False)
			self.update_sud_actions()
			self.update_status_env_label()
			self.setWindowTitle("BrewPi")

	def update_sud_actions(self):
		can_run = self.sud_loaded and not self.sud_empty
		running = can_run and self.sud_state in SUD_RUNNING_STATES
		paused = can_run and self.sud_state == SUD_PAUSED_STATE
		# Start also doubles as Resume while paused; Stop can still abort a
		# paused run, but there's nothing left to Pause once already paused.
		self.actionStart.setEnabled(can_run and not running)
		self.actionPause.setEnabled(running)
		self.actionStop.setEnabled(running or paused)

	def on_system_changed(self, msg):
		print("on_system_changed {}".format(msg))
		for key in msg:
			if "AmbientTemp" in key:
				self.ambient_temp = msg['AmbientTemp']
				# Only sync the entry's text while the user isn't actively
				# editing it, so a server echo doesn't clobber in-progress
				# typing.
				if not self.lineEdit_ambient.hasFocus():
					self.lineEdit_ambient.setText("{:.1f}".format(self.ambient_temp))
			elif "WarpFactor" in key:
				self.warp_factor = msg['WarpFactor']
			elif "PlantSim" in key:
				self.btn_pot_reset.setVisible(msg['PlantSim'])
		self.update_status_env_label()

	def on_action_pot_reset(self):
		self.msg_pot.send({'Reset': True})

	def on_ambient_entry_changed(self):
		try:
			value = float(self.lineEdit_ambient.text())
		except ValueError:
			return
		self.user_config.set('ambient_temperature', value)
		self.msg_system.send({'AmbientTemp': value})

	def update_status_env_label(self):
		ambient = "{:.1f}°C".format(self.ambient_temp) if self.ambient_temp is not None else "-"
		self.status_label_env.setText("Ambient: {}   Warp: {:.1f}x".format(ambient, self.warp_factor))

	@staticmethod
	def _make_window_title(name, description):
		title = "BrewPi"
		if name:
			title += " - {}".format(name)
		if description:
			title += " - {}".format(description)
		return title

	def set_tc_cooling(self, cooling):
		if cooling == self.tc_cooling:
			return
		self.tc_cooling = cooling
		if cooling:
			self.status_label_cooling.setVisible(True)
			self.cooling_blink_timer.start(500)
		else:
			self.cooling_blink_timer.stop()
			self.status_label_cooling.setVisible(False)

	def on_cooling_blink(self):
		self.status_label_cooling.setVisible(not self.status_label_cooling.isVisible())

	def on_slider_temp_soll_changed(self, value):
		print("on_slider_temp_soll_changed {}".format(value))
		self.msg_tempctrl.send({'Soll': {'Temp': value}})

	def on_heatrate_soll_changed(self, value):
		value = round(value, 1)
		print("on_textbox_heatrate_soll_changed {}".format(value))
		self.msg_tempctrl.send({'Soll': {'Rate': value}})

	def on_slider_pwr_soll_changed(self, value):
		print("on_slider_pwr_soll_changed {}".format(value))
		self.msg_heater.send({'Power': value})

	def on_checkbox_changed(self, value):
		print("on_checkbox_changed {}".format(value))
		self.msg_heater.send({'Activate': int(value == 2)})

	def on_slider_stirrer_speed_soll_changed(self, value):
		print("on_slider_stirrer_speed_soll_changed {}".format(value))
		self.msg_stirrer.send({'Speed': value})

	def on_checkbox_stirrer_activate_changed(self, value):
		print("on_checkbox_stirrer_activate_changed {}".format(value))
		self.msg_stirrer.send({'Activate': int(value == 2)})

	def on_checkbox_tc_enable_changed(self, value):
		print("on_checkbox_tc_enable_changed {}".format(value))
		self.msg_tempctrl.send({'Enable': value == 2})

	def on_action_sud_start(self):
		self.msg_sud.send({'Start': True})

	def on_action_sud_pause(self):
		self.msg_sud.send({'Pause': True})

	def on_action_sud_stop(self):
		self.msg_sud.send({'Stop': True})

	def show_user_message(self, message):
		# on_sud_changed() already runs on the GUI thread (via recv_signal),
		# so this can show the dialog directly. The Sud is already blocked
		# in WAIT_USER server-side; closing this dialog is what unblocks it.
		QtWidgets.QMessageBox.information(self, "Sud", message)
		self.msg_sud.send({'Confirm': True})

	def on_action_sud_new(self):
		# Replaces the running Sud's schedule with an empty one, same as
		# Load but with a built-in empty document instead of a file dialog.
		self.msg_sud.send({'Load': {'Name': '', 'Description': '', 'pot_mass': 0, 'pot_material': None, 'steps': []}})

	def on_action_sud_save(self):
		# Pick the destination up front, on the GUI thread - the actual
		# write happens in on_sud_changed(), which runs off a worker thread
		# and must not touch Qt (e.g. open a file dialog) itself.
		start_dir = self.user_config.get('sud_dir', '')
		path, _ = QtWidgets.QFileDialog.getSaveFileName(self, "Save Sud", start_dir, filter="JSON files (*.json)")
		if not path:
			return
		self.user_config.set('sud_dir', str(Path(path).parent))
		self.sud_save_path = path
		self.msg_sud.send({'Save': True})

	def on_action_sud_load(self):
		start_dir = self.user_config.get('sud_dir', '')
		path, _ = QtWidgets.QFileDialog.getOpenFileName(self, "Load Sud", start_dir, filter="JSON files (*.json)")
		if not path:
			return
		self.user_config.set('sud_dir', str(Path(path).parent))
		with open(path) as f:
			data = json.load(f)
		self.msg_sud.send({'Load': data})

	def on_pot_changed(self, msg):
		print("on_pot_changed {}".format(msg))
		for key in msg:
			if "Power" in key:
				self.lcdNumber_power_pot.display(msg['Power'])

	def on_sensor_changed(self, msg):
		print("on_sensor_changed {}".format(msg))

	def on_tempctrl_changed(self, msg):
		print("on_tempctrl_changed {}".format(msg))
		for key in msg:
			if 'State' in key:
				self.label_state.setText(msg['State'])
				self.set_tc_cooling(msg['State'] == 'States.COOL')
			elif "Soll" in key:
				submsg = msg['Soll']
				if 'Temp' in submsg:
					self.plot_temp_soll = submsg['Temp']
					self.lcdNumber_temp_soll.display(str(submsg['Temp']))
					if self.slider_temp_soll_initial_update:
						# blockSignals: setValue() here is just syncing the
						# slider's display to the server's current value, not
						# a user edit - without this it would also fire
						# valueChanged and echo the value straight back as a
						# command.
						self.Slider_temp_soll.blockSignals(True)
						self.Slider_temp_soll.setValue(int(round(submsg['Temp'])))
						self.Slider_temp_soll.blockSignals(False)
						self.slider_temp_soll_initial_update = False
				if 'Rate' in submsg:
					subsubmsg = submsg['Rate']
					for subkey in subsubmsg:
						if "Current" in subkey:
							self.plot_rate_soll = subsubmsg['Current']
							self.lcdNumber_heatrate_soll.display(str(subsubmsg['Current']))
						if "Set" in subkey:
							if self.heatrate_soll_initial_update:
								self.heatrate_soll_initial_update = False
								self.doubleSpinBox_heatrate_soll.blockSignals(True)
								self.doubleSpinBox_heatrate_soll.setValue(subsubmsg['Set'])
								self.doubleSpinBox_heatrate_soll.blockSignals(False)
			elif "Enabled" in key:
				self.tc_enabled = msg['Enabled']
				self.checkbox_tc_enable.blockSignals(True)
				self.checkbox_tc_enable.setChecked(self.tc_enabled)
				self.checkbox_tc_enable.blockSignals(False)
				self.Slider_temp_soll.setEnabled(self.tc_enabled)
				self.doubleSpinBox_heatrate_soll.setEnabled(self.tc_enabled)
			if "Ist" in key:
				submsg = msg['Ist']
				if 'Temp' in submsg:
					self.plot_temp_ist = submsg['Temp']
					self.lcdNumber_temp_ist.display(str(submsg['Temp']))
				if 'Rate' in submsg:
					self.plot_rate_ist = submsg['Rate']
					self.lcdNumber_heatrate_ist.display(str(submsg['Rate']))

	def on_heater_changed(self, msg):
		print("on_heater_changed {}".format(msg))
		for key in msg:
			if "Activate" in key:
				if self.checkbox_heater_activate_initial_update:
					self.checkbox_heater_activate.blockSignals(True)
					self.checkbox_heater_activate.setCheckState(2 if msg['Activate'] == 1 else 0)
					self.checkbox_heater_activate.blockSignals(False)
					self.checkbox_heater_activate_initial_update = False
			elif "PowerSet" in key:
				self.plot_power_set = msg['PowerSet']
			elif "Power" in key:
				self.plot_power_eff = msg['Power']
				self.lcdNumber_power_heater.display(msg['Power'])
				if self.slider_pwr_initial_update:
					# blockSignals: this is a display-only sync of the
					# slider to the heater's current power, not a manual
					# override - letting valueChanged fire here would echo
					# it back as {'Power': ...}, which tasks/heater.py's
					# power_soll = max(power_soll, power_actor) latches as a
					# floor that never goes back down on its own. That's the
					# "stale power > 0 after reconnect" bug.
					self.Slider_pwr_soll.blockSignals(True)
					self.Slider_pwr_soll.setValue(int(round(msg['Power'])))
					self.Slider_pwr_soll.blockSignals(False)
					self.slider_pwr_initial_update = False
			elif "Capabilities" in key:
				submsg = msg['Capabilities']
				if "Power" in submsg:
					submsg = submsg['Power']
					self.Slider_pwr_soll.setMinimum(int(submsg['Min']))
					self.Slider_pwr_soll.setMaximum(int(submsg['Max']))

	def on_stirrer_changed(self, msg):
		print("on_stirrer_changed {}".format(msg))
		for key in msg:
			if "Activate" in key:
				if self.checkbox_stirrer_activate_initial_update:
					self.checkbox_stirrer_activate.blockSignals(True)
					self.checkbox_stirrer_activate.setCheckState(2 if msg['Activate'] == 1 else 0)
					self.checkbox_stirrer_activate.blockSignals(False)
					self.checkbox_stirrer_activate_initial_update = False
			elif "Speed" in key:
				if self.slider_speed_initial_update:
					self.Slider_speed_soll.blockSignals(True)
					self.Slider_speed_soll.setValue(int(round(msg['Speed'])))
					self.Slider_speed_soll.blockSignals(False)
					self.slider_speed_initial_update = False
			elif "Capabilities" in key:
				submsg = msg['Capabilities']
				if "Power" in submsg:
					submsg = submsg['Power']
					self.Slider_speed_soll.setMinimum(int(submsg['Min']))
					self.Slider_speed_soll.setMaximum(int(submsg['Max']))

	def on_sud_changed(self, msg):
		print("on_sud_changed {}".format(msg))
		# Receiving anything at all on this channel means a Sud is loaded
		# server-side - the schedule it's running may still be coming.
		self.sud_loaded = True
		for key in msg:
			if "Json" in key:
				if self.sud_save_path:
					with open(self.sud_save_path, 'w') as f:
						json.dump(msg['Json'], f, indent='\t')
					self.sud_save_path = None
				else:
					self.update_sud_forecast(msg['Json'])
			elif "Name" in key:
				self.statusBar().showMessage("Sud schedule updated: {}".format(msg['Name']), 5000)
				self.setWindowTitle(self._make_window_title(msg.get('Name', ''), msg.get('Description', '')))
			elif "State" in key:
				prev_state = self.sud_state
				self.sud_state = msg['State']

				if self.sud_state in SUD_RUNNING_STATES and self.sud_elapsed_seconds is None:
					self.sud_elapsed_seconds = 0.0
					# Start the dynamic forecast's measured-history trace
					# fresh for this run.
					self.forecast_history = []
				elif self.sud_state not in SUD_RUNNING_STATES and self.sud_state != SUD_PAUSED_STATE:
					was_running = self.sud_elapsed_seconds is not None
					self.sud_elapsed_seconds = None
					# on_plot_timer() only redraws the dynamic forecast while
					# sud_elapsed_seconds is set.
					if was_running:
						# A run just finished or was stopped - leave the
						# dynamic view's last frame (the actual measured
						# history) up rather than recomputing a "static"
						# plan from here, which would walk the *whole*
						# original schedule again starting from wherever
						# the brew happens to have ended up (e.g. close to
						# the last step's target), producing a nonsensical
						# total.
						pass
					elif self.sud_schedule:
						# Fresh load (or reconnecting to an already-idle
						# server) - no run has happened yet, so the upfront
						# plan starting from the current temperature is
						# exactly right.
						start_theta = self.plot_temp_ist if self.plot_temp_ist else 20.0
						self.forecast_plot.show_schedule(self.sud_schedule, start_theta, self.sud_name)

				if self.sud_state == SUD_WAIT_USER_STATE and prev_state != SUD_WAIT_USER_STATE and self.sud_user_message:
					self.show_user_message(self.sud_user_message)
			elif "UserMessage" in key:
				self.sud_user_message = msg['UserMessage']
			elif "Step" in key:
				step = msg['Step']
				self.sud_step_index = step.get('Index')
				self.sud_step_descr = step.get('Descr')
				self.sud_step_type = step.get('Type')
				# Stale for the step that just ended - the server is
				# already recomputing it (see on_plot_timer()'s fallback
				# to the naive estimate in the meantime).
				self.server_remaining_forecast = None
				self.update_status_step_label()
			elif "HoldRemaining" in key:
				self.sud_hold_remaining = msg['HoldRemaining']
				self.update_status_step_label()
			elif "Elapsed" in key:
				self.sud_elapsed_seconds = msg['Elapsed']
			elif "RemainingForecast" in key:
				forecast = msg['RemainingForecast']
				# Anchor to elapsed_min as of receipt - close enough to
				# when the server actually computed it (it's seeded from
				# the live theta_ist at that moment) - rather than the
				# live elapsed_min on_plot_timer() sees on later ticks.
				anchor_min = self._elapsed_min()
				if anchor_min is not None:
					self.server_remaining_forecast = (anchor_min, forecast['T'], forecast['Theta'])
			elif "Forecast" in key:
				self.on_sud_forecast_received(msg['Forecast'])
		self.update_sud_actions()

	def on_sud_forecast_received(self, forecast):
		# The server computes this asynchronously (it simulates the whole
		# schedule) and it can arrive slightly after the schedule itself -
		# only apply it if we're still looking at the static "not running
		# yet" preview show_schedule() drew; a run already in progress (or
		# one that's since finished) owns the plot via show_dynamic()/its
		# frozen last frame instead.
		if self.sud_empty or self.sud_elapsed_seconds is not None:
			return
		t_min = [seconds / 60.0 for seconds in forecast['T']]
		self.forecast_plot.show_precomputed_course(t_min, forecast['Theta'], self.sud_name)

	def update_status_step_label(self):
		if not self.sud_step_descr:
			self.statusBar().clearMessage()
			return
		text = "Step {}: {}".format(self.sud_step_index, self.sud_step_descr)
		if self.sud_step_type == 'hold':
			remaining = max(self.sud_hold_remaining, 0.0)
			text += " ({:.0f}:{:02.0f} remaining)".format(remaining // 60, remaining % 60)
		self.statusBar().showMessage(text)

	def update_sud_forecast(self, doc):
		try:
			name, _, schedule, _, _ = Sud._parse_data(doc)
		except (KeyError, TypeError):
			return
		self.sud_name = name
		self.sud_schedule = schedule
		self.sud_empty = len(schedule) == 0
		self.update_sud_actions()
		if self.sud_empty:
			self.forecast_plot.show_no_schedule()
			return
		# No measured starting temperature is available before a brew has
		# started; fall back to a plausible ambient guess. If a run is
		# already in progress (e.g. reconnecting mid-brew), the next
		# on_plot_timer() tick switches this over to the dynamic view.
		start_theta = self.plot_temp_ist if self.plot_temp_ist else 20.0
		self.forecast_plot.show_schedule(schedule, start_theta, name)

	def closeEvent(self, event):
		print("Exitting gracefully!")
		self.ws_client.disconnect()


if __name__ == '__main__':
	app = QtWidgets.QApplication(sys.argv)
	win = Window()
	win.show()
	sys.exit(app.exec_())

	print ("End of program.")