#!/usr/bin/env python
import requests
from datetime import datetime, timedelta
from collections import defaultdict
import json
import os, sys
import pytz
import argparse

URL= "https://maps.googleapis.com/maps/api/distancematrix/json"

parser = argparse.ArgumentParser(description='Plot traffic information for various origin-destinations')
parser.add_argument('-c', '--config', type=str, default='config.json', help='Config file to load (default config.jsonà')
parser.add_argument('-n', '--dry-run', action='store_true', help='Run in dry-run mode (don’t make any api call)')
parser.add_argument('-d', '--date', type=str, default='now', help='date (%%Y-%%m-%%d) for which to generate the plots')
parser.add_argument('-s', '--stats', action='store_true', help='only print number of weekly calls for the config')
args = parser.parse_args()

WEEKDAYS = ["monday", "tuesday", "wednesday", "thursday", "friday", "saturday", "sunday"]
SETTINGS = json.load(open(args.config, "r"))

if args.date == "now":
    date = datetime.now(tz=pytz.timezone("Europe/Paris"))
else:
    date = datetime.strptime(args.date, "%Y-%m-%d").replace(tzinfo=pytz.timezone("Europe/Paris"))

def parse_plot(info):
    def condition(d):
        return "days" not in info or WEEKDAYS[d.weekday()] in info["days"]
    return {
            "name": info["name"],
            "origin": SETTINGS.get("locations", {}).get(info["origin"], info["origin"]),
            "destination": SETTINGS.get("locations", {}).get(info["destination"], info["destination"]),
            "condition": condition,
            "times": [t.split(":") for t in info["times"]],
            }

plots = {}
for name,info in SETTINGS["plots"].items():
    plots[name] = parse_plot(info)

def to_time(date, hour, minute):
    return date.replace(date.year, date.month, date.day, int(hour), int(minute), 0, 0)

def get(time, origin, destination):
    keys = {
            "origins": origin,
            "destinations": destination,
            "departure_time": int(time.timestamp()),
            "key": SETTINGS["api_key"],
            }
    return requests.get(URL, params=keys)

def stats():
    total_calls_per_week = 0
    for k, infos in plots.items():
        calls_per_week = 0
        for i in range(0, 7):
            if infos["condition"](date + timedelta(i)):
                calls_per_week += 1
        total_calls_per_week += calls_per_week * len(infos["times"])
    print("{} calls per week to api".format(total_calls_per_week))
if args.stats:
    stats()
    sys.exit(0)

gnuplot = """
reset
set terminal png size 1024,768 enhanced font "Helvetica"
set output 'outputs/{fname}.png'
set datafile separator "\\t"
set xlabel "Time"
set ylabel "Duration"

set xdata time
set timefmt "%H:%M"
set format x "%H:%M"
set title "{date} {name}"
plot '{fname}.dat' using 1:2 with linespoints pointtype 5 title ""
"""

def get_times(name, infos, date, dry_run=False):
    result = {}
    if "condition" in infos and not infos["condition"](date):
        return result
    for time in infos["times"]:
        t = to_time(date, time[0], time[1])
        try:
            if dry_run:
                v = 42
            else:
                v = get(t, infos["origin"], infos["destination"]).json()
                v = int(v["rows"][0]["elements"][0]["duration_in_traffic"]["value"] / 60)
        except:
            continue
        result[t.strftime("%H:%M")] = v
    with open(date.strftime("%Y-%m-%d_{}.json".format(name)), "w") as f:
        f.write(json.dumps(result, indent=True))

    fname = date.strftime("%Y-%m-%d_{}".format(name))
    with open("{}.dat".format(fname), "w") as f:
        for time, duration in result.items():
            f.write('{}\t{}\n'.format(time, duration))
    with open("{}.gnuplot".format(fname), "w") as f:
        f.write(gnuplot.format(**{
            "fname": fname,
            "name": infos["name"],
            "date": date.strftime("%Y-%m-%d")
            }))
    os.system("gnuplot -c {}.gnuplot".format(fname))
    return result

for name, infos in plots.items():
    get_times(name, infos, date, dry_run=args.dry_run)