helpers.py

# -*- coding: utf-8 -*-


import i18n

import datetime
from threading import Thread
import os
import errno
import random
import sys
import time
import subprocess
import io
import codecs
import ast
from web.webapi import seeother
from blinker import signal

import web
from web import form

import gv
from web.session import sha1

try:
    from gpio_pins import GPIO, pin_rain_sense, pin_relay
    if gv.use_pigpio:
        import pigpio
        pi = pigpio.pi()
except ImportError:
    print 'error importing GPIO pins into helpers'
    pass

try:
    import json
except ImportError:
    try:
        import simplejson as json
    except ImportError:
        print _("Error: json module not found")
        sys.exit()


##############################
#### Function Definitions ####

station_completed = signal('station_completed')
def report_station_completed(station):
    """
    Send blinker signal indicating that a station has completed.
    Include the station number as data.
    """
    station_completed.send(station)

stations_scheduled = signal('stations_scheduled')
def report_stations_scheduled(txt=None):
    """
    Send blinker signal indicating that stations had been scheduled.
    """
    stations_scheduled.send('SIP',txt=txt)


rain_changed = signal('rain_changed')
def report_rain_changed(txt=None):
    """
    Send blinker signal indicating that rain sensor changed.
    """
    rain_changed.send()


restarting = signal('restart') #: Signal to send on software restart
def report_restart():
    """
    Send blinker signal indicating system will restart.
    """
    restarting.send()

def reboot(wait=1, block=False):
    """
    Reboots the Raspberry Pi from a new thread.
    
    @type wait: int
    @param wait: length of time to wait before rebooting
    @type block: bool
    @param block: If True, clear output and perform reboot after wait.
        Set to True at start of thread (recursive).
    """
    if block:
        from gpio_pins import set_output
        gv.srvals = [0] * (gv.sd['nst'])
        set_output()
        if gv.use_pigpio:
            pass
        else:
            GPIO.cleanup()
        time.sleep(wait)
        try:
            print _('Rebooting...')
        except Exception:
            pass
        subprocess.Popen(['reboot'])
    else:
        t = Thread(target=reboot, args=(wait, True))
        t.start()


def poweroff(wait=1, block=False):
    """
    Powers off the Raspberry Pi from a new thread.
    
    @type wait: int or float
    @param wait: number of seconds to wait before rebooting
    @type block: bool
    @param block: If True, clear output and perform reboot after wait.
        Set to True at start of thread (recursive).
    """
    if block:
        from gpio_pins import set_output
        gv.srvals = [0] * (gv.sd['nst'])
        set_output()
        if gv.use_pigpio:
            pass
        else:
            GPIO.cleanup()
        time.sleep(wait)
        try:
            print _('Powering off...')
        except Exception:
            pass
        subprocess.Popen(['poweroff'])
    else:
        t = Thread(target=poweroff, args=(wait, True))
        t.start()


def restart(wait=1, block=False):
    """
    Restarts the software from a new thread.
    
    @type wait: int
    @param wait: length of time to wait before rebooting
    @type block: bool
    @param block: If True, clear output and perform reboot after wait.
        Set to True at start of thread (recursive).
    """
    if block:
        report_restart()
        from gpio_pins import set_output
        gv.srvals = [0] * (gv.sd['nst'])
        set_output()
        if gv.use_pigpio:
            pass
        else:
            GPIO.cleanup()
        time.sleep(wait)
        try:
            print _('Restarting...')
        except Exception:
            pass
        gv.restarted = 0
        subprocess.Popen('systemctl restart sip.service'.split())
    else:
        t = Thread(target=restart, args=(wait, True))
        t.start()


def uptime():
    """
    Returns UpTime for RPi
    
    @rtype: String
    @return: Length of time System has been running.
    """
    string = 'Error 1: uptime'

    with open("/proc/uptime") as f:
        total_sec = float(f.read().split()[0])
        string = str(datetime.timedelta(seconds=total_sec)).split('.')[0]

    return string


def get_ip():
    """
    Returns the IP address of the system if available.
    """
    try:
        arg = 'ip route list'
        p = subprocess.Popen(arg, shell=True, stdout=subprocess.PIPE)
        data = p.communicate()
        split_data = data[0].split()
        ipaddr = split_data[split_data.index('src') + 1]
        return ipaddr
    except:
        return "No IP Settings"


def get_rpi_revision():
    """
    Returns the hardware revision of the Raspberry Pi
    using the RPI_REVISION method from RPi.GPIO.
    """
    try:
        import RPi.GPIO as GPIO

        return GPIO.RPI_REVISION
    except ImportError:
        return 0

def mkdir_p(path):
    try:
        os.makedirs(path)
    except OSError as exc:  # Python >2.5
        if exc.errno == errno.EEXIST and os.path.isdir(path):
            pass
        else:
            raise

def check_rain():
    """
    Checks status of an installed rain sensor.
    
    Handles normally open and normally closed rain sensors
    
    Sets gv.sd['rs'] to 1 if rain is detected otherwise 0.
    """

    global pi
    try:
        if gv.sd['rst'] == 1:  # Rain sensor type normally open (default)
            if gv.use_pigpio:
                if not pi.read(pin_rain_sense):  # Rain detected
                    gv.sd['rs'] = 1
                else:
                    gv.sd['rs'] = 0
            else:
                if GPIO.input(pin_rain_sense) == gv.sd['rs']: #  Rain sensor changed, reading and gv.sd['rs'] are inverse.
                    report_rain_changed()
                    gv.sd['rs'] = 1 - gv.sd['rs'] #  toggle
        elif gv.sd['rst'] == 0:  # Rain sensor type normally closed
            if gv.use_pigpio:
                if pi.read(pin_rain_sense):  # Rain detected
                    gv.sd['rs'] = 1
                else:
                    gv.sd['rs'] = 0
            else:
                if GPIO.input(pin_rain_sense) != gv.sd['rs']:  # Rain sensor changed
                    report_rain_changed()
                    gv.sd['rs'] = 1 - gv.sd['rs'] #  toggle
    except NameError:
        pass


def clear_mm():
    """
    Clear manual mode settings and stop any running zones.
    """
    from gpio_pins import set_output
    if gv.sd['mm']:
        gv.sbits = [0] * (gv.sd['nbrd'] + 1)
        gv.ps = []
        for i in range(gv.sd['nst']):
            gv.ps.append([0, 0])
        gv.rs = []
        for i in range(gv.sd['nst']):
            gv.rs.append([0, 0, 0, 0])
        gv.srvals = [0] * (gv.sd['nst'])
        set_output()
    return


def plugin_adjustment():
    """
    Sums irrigation time (water level) adjustments from multiple plugins.
    
    The adjustment value output from a plugin must be 
    a unique element in the gv.sd dictionary with a key starting with 'wl_'
    
    @rtype:   float
    @return:  Total irrigation time adjustments for all active plugins
    """
    duration_adjustments = [gv.sd[entry] for entry in gv.sd if entry.startswith('wl_')]
    result = reduce(lambda x, y: x * y / 100, duration_adjustments, 1.0)
    return result


def get_cpu_temp(unit=None):
    """
    Reads and returns the temperature of the CPU if available.
    If unit is F, temperature is returned as Fahrenheit otherwise Celsius.
    
    @type unit: character
    @param unit: F or C        
    @rtype:   string
    @return:  CPU temperature
    """

    try:
        if gv.platform == 'bo':
            res = os.popen('cat /sys/class/hwmon/hwmon0/device/temp1_input').readline()
            temp = str(int(float(res) / 1000))
        elif gv.platform == 'pi':
            command = "cat /sys/class/thermal/thermal_zone0/temp"
            output = subprocess.check_output(command.split())
            temp = str(int(float(output) / 1000))
        else:
            temp = str(0)

        if unit == 'F':
            return str(1.8 * float(temp) + 32)
#            return str(9.0 / 5.0 * float(temp) + 32)
        elif unit is not None:
            return str(float(temp))
        else:
            return temp
    except Exception:
        return '!!'


def timestr(t):
    """
    Convert duration in seconds to string in the form mm:ss.
      
    @type  t: int
    @param t: duration in seconds
    @rtype:   string
    @return:  duration as "mm:ss"   
    """
    return str((t / 60 >> 0) / 10 >> 0) + str((t / 60 >> 0) % 10) + ":" + str((t % 60 >> 0) / 10 >> 0) + str(
        (t % 60 >> 0) % 10)


def log_run():
    """
    Add run data to json log file - most recent first.
    
    If a record limit is specified (gv.sd['lr']) the number of records is truncated.  
    """

    if gv.sd['lg']:
        program = _('program')
        station = _('station')
        duration = _('duration')
        strt = _('start')
        date = _('date')
        if gv.lrun[1] == 98:
            pgr = _('Run-once')
        elif gv.lrun[1] == 99:
            pgr = _('Manual')
        else:
            pgr = str(gv.lrun[1])
        start = time.gmtime(gv.now - gv.lrun[2])
        logline = '{"'+program+'":"' + pgr + '","'+station+'":' + str(gv.lrun[0]) + ',"'+duration+'":"' + timestr(
            gv.lrun[2]) + '","'+strt+'":"' + time.strftime('%H:%M:%S","'+date+'":"%Y-%m-%d"', start) + '}'
        lines = []
        lines.append(logline + '\n')
        log = read_log()
        for r in log:
            lines.append(json.dumps(r) + '\n')
        with codecs.open('./data/log.json', 'w', encoding='utf-8') as f:
            if gv.sd['lr']:
                f.writelines(lines[:gv.sd['lr']])
            else:
                f.writelines(lines)
    return


def prog_match(prog):
    """
    Test a program for current date and time match.
    """
    if not prog[0]:
        return 0  # Skip if program is not enabled
    devday = int(gv.now / 86400)  # Check day match
    lt = time.gmtime(gv.now)
    if (prog[1] >= 128) and (prog[2] > 1):  # Interval program
        if (devday % prog[2]) != (prog[1] - 128):
            return 0
    else:  # Weekday program
        if not prog[1] - 128 & 1 << lt[6]:
            return 0
        if prog[1] >= 128 and prog[2] == 0:  # even days
            if lt[2] % 2 != 0:
                return 0
        if prog[1] >= 128 and prog[2] == 1:  # Odd days
            if lt[2] == 31 or (lt[1] == 2 and lt[2] == 29):
                return 0
            elif lt[2] % 2 != 1:
                return 0
    this_minute = (lt[3] * 60) + lt[4]  # Check time match
    if this_minute < prog[3] or this_minute >= prog[4]:
        return 0
    if prog[5] == 0:
        return 0
    if ((this_minute - prog[3]) / prog[5]) * prog[5] == this_minute - prog[3]:
        return 1  # Program matched
    return 0


def schedule_stations(stations):
    """
    Schedule stations/valves/zones to run.
    """
    if gv.sd['rd'] or (gv.sd['urs'] and gv.sd['rs']):  # If rain delay or rain detected by sensor
        rain = True
    else:
        rain = False
    accumulate_time = gv.now
    if gv.sd['seq']:  # sequential mode, stations run one after another
        for b in range(len(stations)):
            for s in range(8):
                sid = b * 8 + s  # station index
                if gv.rs[sid][2]:  # if station has a duration value
                    if not rain or gv.sd['ir'][b] & 1 << s:  # if no rain or station ignores rain
                        gv.rs[sid][0] = accumulate_time  # start at accumulated time
                        accumulate_time += gv.rs[sid][2]  # add duration
                        gv.rs[sid][1] = accumulate_time  # set new stop time
                        accumulate_time += gv.sd['sdt']  # add station delay
                    else:
                        gv.sbits[b] &= ~1 << s
                        gv.ps[s] = [0, 0]
    else:  # concurrent mode, stations allowed to run in parallel
        for b in range(len(stations)):
            for s in range(8):
                sid = b * 8 + s  # station index
                if not stations[b] & 1 << s:  # skip stations not in prog
                    continue
                if gv.rs[sid][2]:  # if station has a duration value
                    if not rain or gv.sd['ir'][b] & 1 << s:  # if no rain or station ignores rain
                        gv.rs[sid][0] = gv.now  # accumulate_time # set start time
                        gv.rs[sid][1] = (gv.now + gv.rs[sid][2])  # set stop time
                    else:  # if rain and station does not ignore, clear station from display
                        gv.sbits[b] &= ~1 << s
                        gv.ps[s] = [0, 0]
    report_stations_scheduled()
    gv.sd['bsy'] = 1
    return


def stop_onrain():
    """
    Stop stations that do not ignore rain.
    """

    from gpio_pins import set_output
    do_set_output = False
    for b in range(gv.sd['nbrd']):
        for s in range(8):
            sid = b * 8 + s  # station index
            if gv.sd['ir'][b] & 1 << s:  # if station ignores rain...
                continue
            elif not all(v == 0 for v in gv.rs[sid]):
                gv.srvals[sid] = 0
                do_set_output = True
                gv.sbits[b] &= ~1 << s  # Clears stopped stations from display
                gv.ps[sid] = [0, 0]
                gv.rs[sid] = [0, 0, 0, 0]

    if do_set_output:
        set_output()
    return


def stop_stations():
    """
    Stop all running stations, clear schedules.
    """
    from gpio_pins import set_output
    gv.srvals = [0] * (gv.sd['nst'])
    set_output()
    gv.ps = []
    for i in range(gv.sd['nst']):
        gv.ps.append([0, 0])
    gv.sbits = [0] * (gv.sd['nbrd'] + 1)
    gv.rs = []
    for i in range(gv.sd['nst']):
        gv.rs.append([0, 0, 0, 0])
    gv.sd['bsy'] = 0
    return


def read_log():
    """
    
    """
    result = []
    try:
        with io.open('./data/log.json') as logf:
            records = logf.readlines()
            for i in records:
                try:
                    rec = ast.literal_eval(json.loads(i))
                except ValueError:
                    rec = json.loads(i)
                result.append(rec)
        return result
    except IOError:
        return result


def jsave(data, fname):
    """
    Save data to a json file.
    
    
    """
    with open('./data/' + fname + '.json', 'w') as f:
        json.dump(data, f, indent=4, sort_keys=True)


def station_names():
    """
    Load station names from /data/stations.json file if it exists
    otherwise create file with defaults.
    
    Return station names as a list.
    
    """
    try:
        with open('./data/snames.json', 'r') as snf:
            return json.load(snf)
    except IOError:
        stations = [u"S01", u"S02", u"S03", u"S04", u"S05", u"S06", u"S07", u"S08"]
        jsave(stations, 'snames')
        return stations


def load_programs():
    """
    Load program data into memory from /data/programs.json file if it exists.
    otherwise create an empty programs data list (gv.pd).
    
    """
    try:
        with open('./data/programs.json', 'r') as pf:
            gv.pd = json.load(pf)
    except IOError:
        gv.pd = []  # A config file -- return default and create file if not found.
        with open('./data/programs.json', 'w') as pf:
            json.dump(gv.pd, pf, indent=4, sort_keys=True)
    return gv.pd


def password_salt():
    """
    Generate random number for use as salt for password encryption
    
    @rtype: string
    @return: random value as 64 byte string.
    """
    return "".join(chr(random.randint(33, 127)) for _ in xrange(64))


def password_hash(password, salt):
    """
    Generate password hash using sha-1.
    
    @type: string
    @param param: password
    @type param: string
    @param: salt 
    """
    return sha1(password + salt).hexdigest()


########################
#### Login Handling ####

def check_login(redirect=False):
    """
    Check login.
    """
    qdict = web.input()

    try:
        if gv.sd['ipas'] == 1:
            return True

        if web.config._session.user == 'admin':
            return True
    except KeyError:
        pass

    if 'pw' in qdict:
        if gv.sd['password'] == password_hash(qdict['pw'], gv.sd['salt']):
            return True
        if redirect:
            raise web.unauthorized()
        return False

    if redirect:
        raise web.seeother('/login')
    return False


signin_form = form.Form(
    form.Password('password', description = _('Password') + ':'),
    validators=[
        form.Validator(
            _("Incorrect password, please try again"),
            lambda x: gv.sd['password'] == password_hash(x.password, gv.sd['salt'])
        )
    ]
)


def get_input(qdict, key, default=None, cast=None):
    """
    Checks data returned from a UI web page.
    
    
    """
    result = default
    if key in qdict:
        result = qdict[key]
        if cast is not None:
            result = cast(result)
    return result