#!micropython
print("Start main.py")
import json
import time
import machine
import socket
import micropython as mp

from nodemcu_gpio_lcd import GpioLcd
from machine import Pin, PWM
import network

backlight = PWM(Pin(12), freq=500, duty=200)

wlan = network.WLAN()

lcd = GpioLcd(rs_pin=Pin(16), enable_pin=Pin(5), 
        d4_pin=Pin(4), d5_pin=Pin(0), d6_pin=Pin(2), d7_pin=Pin(14), 
        num_lines=2, num_columns=16)

lcd.clear()
lcd.putstr("Verbinde mit:\n{}".format(wlan.config('essid')))
while not wlan.isconnected():
    continue
lcd.clear()
lcd.putstr("Verbunden")

HOST = b'www.localnet.cc'
HEADERS = b'Host: www.localnet.cc\r\nConnection: close\r\n\r\n'

displays = [
        { #          ################     ################   <- 16 chars
            "name": "Zusammenfassung " + "                ",
            "text": "I: ____ E: ____ " + "W: ____ßS: ____ß",
            "values" : [
                """SELECT sum("d4_count")*30 FROM "stromzaehler3" WHERE time > now() - 2m""",
                """SELECT sum("d1_count")*30 FROM "stromzaehler3" WHERE time > now() - 2m""",
                """SELECT last(value) FROM temp0 WHERE sensor = '28-8B-DC-E9-16-13-01-D5'""",
                """SELECT last(value) FROM temp0 WHERE sensor = '28-7F-69-16-17-13-01-A6'""",
                ]
            },
        { #          ################     ################   <- 16 chars
            "name": "Stromz\xe1hler     " + "   Heute        ",
            "text": "\xf6 Import  ____Wh" + "\xf6 Export  ____Wh",
            "values" : [
                "SELECT last(sum) FROM (SELECT sum(d4_count) FROM stromzaehler3 WHERE time > now() - 1d GROUP BY time(1d)  tz('Europe/Berlin'))",
                "SELECT last(sum) FROM (SELECT sum(d1_count) FROM stromzaehler3 WHERE time > now() - 1d GROUP BY time(1d)  tz('Europe/Berlin'))",
                ],
            },
        { #          ################     ################   <- 16 chars
            "name": "Heizung Solar   " + "                ",
            "text": "Von Dach: ____ß " + "Zum Dach: ____ß ",
            "values" : [
                "SELECT last(value) FROM temp0 WHERE sensor = '28-7F-69-16-17-13-01-A6'",
                "SELECT last(value) FROM temp0 WHERE sensor = '28-99-38-EB-16-13-01-22'",
                ]
            },
        { #          ################     ################   <- 16 chars
            "name": "BFT Rheinau     " + "                ",
            "text": "S95-E5:  __.___ " + "Diesel:  __.___ ",
            "values" : [
                """SELECT last(value) FROM "tankerkoenig.SP95-E5" WHERE "name" = 'Rheinau-Freistett - BFT - Freistett'""",
                """SELECT last(value) FROM "tankerkoenig.Diesel" WHERE "name" = 'Rheinau-Freistett - BFT - Freistett'""",
                ]},
            ]

def query_one(db, select):
    select_esc = select.replace(" ", "%20")
    select_esc = select_esc.replace("\"", "%22")
    addr = socket.getaddrinfo(HOST, 80)[0][-1]
    s = socket.socket()
    s.connect(addr)
    s.send(b'GET /grafana/api/datasources/proxy/3/query?db={}&q={}&epoch=ms\r\n'.format(db, select_esc))
    s.send(HEADERS)
    data = json.load(s)
    s.close()
    return data['results'][0]['series'][0]['values'][0][1]

current_display = 0
def update():
    global UPDATE_RUN, current_display, display, lcd

    lcd.move_to(0, 0)
    text = displays[current_display]["text"]

    s = ""
    cur = ""
    pos = 0
    i = 0
    while i<len(text):
        c = text[i]
        cur_added = False
        if c == '_' or ( len(cur) > 0 and c == '.' ):
            cur += c
            cur_added = True

        if len(cur) > 0 and (not cur_added or i == len(text) - 1):
            value_query = displays[current_display]["values"][pos]
            v = query_one("data", value_query)
            if isinstance(v, float):
                if "." in cur:
                    precision = len(cur) - cur.index(".") - 1
                else:
                    precision = 0
                fmt_string = "{{: >{}.{}f}}".format(len(cur), precision)
            elif isinstance(v, int):
                fmt_string = "{{: >{}d}}".format(len(cur))
            else:
                raise Exception("Wrong type: {}".format(type(v)))
            s += fmt_string.format(v)
            lcd.putstr(s)
            s = ""
            cur = ""
            pos += 1

        if not cur_added:
            s += c

        if not cur_added and i == len(text)-1:
            lcd.putstr(s)
            s = ""

        i += 1

    lcd.putstr(s)

last_update = 0

def schedule_update(timer=None, force=False):
    global last_update
    def ex(none):
        try:
            update()
        except Exception as e:
            lcd.clear()
            msg = "Error: {}".format(str(e)[0:(32-7)])
            lcd.putstr(msg)
            raise e

    now = time.ticks_ms()
    if force:
        last_update = now
        ex(None)
    elif now - last_update > 5000:
        last_update = now
        mp.schedule(ex, None)

timer = machine.Timer(-1)

def switch_display(none):
    global current_display, displays

    current_display += 1
    current_display %= len(displays)
    lcd.move_to(0,0)
    lcd.putstr(displays[current_display]['name'])

    # trigger update in 1s
    last_update = time.ticks_ms() - 4000

last_switch = 0
def switch_pressed(pin):
    global last_switch
    now = time.ticks_ms()
    if pin.value() == 0 and now - last_switch > 200:
        mp.schedule(switch_display, None)
        last_switch = now

switch = machine.Pin(13, machine.Pin.IN)
switch.irq(switch_pressed)

timer.init(period=500, mode=machine.Timer.PERIODIC, callback=schedule_update)

print("main.py finished")