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#!/usr/bin/env python3
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"""
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rain.py — watch it rain in your terminal.
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Light rain in Helsinki, +3°C, Monday afternoon.
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"""
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​
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import random
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import time
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import os
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import sys
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​
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# Terminal size
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try:
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    cols, rows = os.get_terminal_size()
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except OSError:
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    cols, rows = 80, 24
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​
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# Rain characters — lighter to heavier
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DROPS = [".", ":", "|", "!", "/", "\\"]
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SPLASH = ["·", "°", "~", "˙", "'"]
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PUDDLE = ["≈", "~", "—", "_"]
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​
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class Raindrop:
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    def __init__(self, cols, rows):
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        self.x = random.randint(0, cols - 1)
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        self.y = 0
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        self.speed = random.choice([1, 1, 1, 2])  # mostly slow — light rain
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        self.char = random.choice(DROPS[:3])  # light rain = light characters
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        self.wind = random.choice([0, 0, 0, 1])  # slight northeast wind
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​
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    def fall(self):
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        self.y += self.speed
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        self.x += self.wind
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        if self.x >= cols:
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            self.x = 0
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​
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class Splash:
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    def __init__(self, x, y, cols):
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        self.x = x
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        self.y = y
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        self.char = random.choice(SPLASH)
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        self.life = random.randint(1, 3)
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​
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    def age(self):
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        self.life -= 1
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​
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def render(drops, splashes, rows, cols, frame):
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    grid = [[" "] * cols for _ in range(rows)]
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​
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    # Ground puddles — subtle
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    for c in range(cols):
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        if random.random() < 0.03:
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            grid[rows - 1][c] = random.choice(PUDDLE)
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​
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    # Splashes
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    for s in splashes:
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        if 0 <= s.y < rows and 0 <= s.x < cols:
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            grid[s.y][s.x] = s.char
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​
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    # Drops
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    for d in drops:
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        if 0 <= d.y < rows and 0 <= d.x < cols:
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            grid[d.y][d.x] = d.char
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​
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    # Temperature in corner
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    temp = "+3°C"
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    if cols > 20:
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        for i, ch in enumerate(temp):
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            if i < cols:
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                grid[0][cols - len(temp) + i] = ch
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​
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    return "\n".join("".join(row) for row in grid)
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​
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def main():
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    drops = []
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    splashes = []
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    frame = 0
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​
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    print("\033[2J\033[H", end="")  # clear screen
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    print("\033[?25l", end="")  # hide cursor
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​
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    try:
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        while True:
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            # Spawn new drops — light rain = fewer drops
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            for _ in range(random.randint(1, 3)):
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                drops.append(Raindrop(cols, rows - 1))
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​
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            # Move drops
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            new_drops = []
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            for d in drops:
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                d.fall()
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                if d.y >= rows - 1:
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                    # Hit ground — maybe splash
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                    if random.random() < 0.4:
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                        splashes.append(Splash(d.x, rows - 1, cols))
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                else:
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                    new_drops.append(d)
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            drops = new_drops
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​
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            # Age splashes
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            new_splashes = []
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            for s in splashes:
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                s.age()
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                if s.life > 0:
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                    new_splashes.append(s)
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            splashes = new_splashes
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​
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            # Render
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            output = render(drops, splashes, rows - 1, cols, frame)
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            print(f"\033[H{output}", end="", flush=True)
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​
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            frame += 1
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            time.sleep(0.15)
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​
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    except KeyboardInterrupt:
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        print("\033[?25h", end="")  # show cursor
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        print("\033[2J\033[H", end="")  # clear
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        print("the rain continues without you watching.")
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​
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if __name__ == "__main__":
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    main()
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​