#!/usr/bin/python3
# -*- coding: utf-8 -*-


import os, sys, termios, tty, time, random
from math import sin, cos, tan, sqrt
from time import sleep

# Randomly choose a cow
cows = "🐵🐒🦍🦧🐕🐯🦝🐩🐅🐴🐎🦄🦌🐗🐂🐃🐄🐪🐫🦙🦒🐹🦘🦡🐧🕊️🦅🦆🦉🐍🦎🐊🦜🦚🦩🐲🐉🦕"
cowlistlength = len(cows)
cow = cows[random.randint(0, cowlistlength - 1)]
cowlength = len(cow)

# Needed: find our screensize
termsize_xy = os.get_terminal_size()
xmax = termsize_xy[0] - 1
ymax = termsize_xy[1]
ymin = 0
xmin = 0
xold = xmin

# pi is not defined by default
pi = 3.1416
deg2rad = pi / 180

# position cursor at x,y - where x=0 y=0 is the left lower corner like in mathematical diagrams
def curpos(x, y):
    print("\033[%d;%dH" % (ymax - y, x), end="", flush=True)


outputfile = open("cowyeetflugbahn.txt", "w")

# CTRL and ESC-codes for the used outputdevice. Probably a terminal.
clear, home, curoff, curon = "'\x1b[2J\x1b[H", "\x1b[H", "\x1b[?25l", "\x1b[?25h"


# some scales, we need
# not everything has to be recomputed in loops.
xsteps = xmax
x = 0
y = x**2
erde = 9.81
mond = 1.6
jupiter = 24
gravitation = erde
# in scala the resulting coordinates will be returned
scala = []

# used, if input is disabled
starthoehe = 0
startwinkel = 26 * deg2rad
startgeschwindigkeit = 36
loeschen = "y"

bla = input("Parameter editieren (y) oder Vorgabe nutzen?")
if bla == "y":
    # Be a friendly host, lets have a talk.
    # comment out to speed up testing
    starthoehe = float(input("Starthöhe in Metern, empf: 0-20: "))
    startwinkel = float(input("Startwinkel 0° - 90°: ")) * deg2rad
    startgeschwindigkeit = float(input("Startgeschwindigkeit Meter (zb 20) pro Sekunde: "))
    loeschen = input("Kuh löschen? (y/n)")
####

# Calculate time of flight
flugdauer = startgeschwindigkeit * sin(startwinkel) / gravitation
schlafdauer = flugdauer / xmax
# Calculate maximum height
hoehe = 0.5 * gravitation * flugdauer**2 + starthoehe

# calculate length of flight
wurfweite = (
    startgeschwindigkeit
    * cos(startwinkel)
    * (startgeschwindigkeit * sin(startwinkel) + sqrt(startgeschwindigkeit**2 * sin(startwinkel) ** 2 + 2 * gravitation * starthoehe))
) / gravitation


# init screen and wait for userinput

print(clear, curoff)
print(
    "xteps: ",
    xsteps,
    "\nwurfweite: ",
    wurfweite,
    "\nstartwinkel: ",
    startwinkel / deg2rad,
    "\nstartgeschwindigkeit: ",
    startgeschwindigkeit,
    "\nstarthoehe: ",
    starthoehe,
    "\nhoehe: ",
    hoehe,
    "\nschlafdauer: ",
    schlafdauer,
)

bla = input("CR please:")

# position cursor down left corner
curpos(1, ymax)

# cowlength is 2, if cow is an UTF8-Icon, otherwise 1
for x in range(xmin, xsteps - 1, cowlength):
    # the formula, which generates the y position for the corresponding x, shamelessly ripped from some schoolbook and modified.
    yold = y
    y = (-(gravitation / (2 * startgeschwindigkeit**2 * cos(startwinkel) ** 2)) * x**2) + (tan(startwinkel) * x + starthoehe)

    time.sleep(schlafdauer)
    # Ensure, that nothing has to be drawn outside the viewport
    if y < ymax and y > ymin:
        curpos(x, y)
        print(cow, end="")
        # Stash awa the coordinates into scala, which will be returned
        scala += [x, int(y * 10 + 5) / 10]
        if loeschen == "y":
            curpos(xold, yold)
            print(" ", end="")
    else:
        scala += [x, 0]

    xold = x

curpos(0, 0)
outputfile.write(str(scala))
sys.exit(curon + "Moooooooooooo.")