#!/usr/bin/env python3
"""Turn static building sprites into looping pulse animations.

For each building sprite: find its glowing pixels (high saturation or very
bright — the pink trims, blue rings, neon), then emit N frames where those
pixels breathe between base and boosted brightness on a sine. WithSpriteBody
PlayRepeating()s the idle sequence, so multi-frame sheets animate for free.

Regenerates <name>.png in sequences/assets as an N-frame sheet and rewrites the
matching `idle:` block in sequences/economy.yaml (Length + Tick).
Safe to re-run: it always starts from assets_src frame-0 backups it maintains.
"""
import math, os, re, shutil
from PIL import Image
from PIL.PngImagePlugin import PngInfo

ROOT = os.path.join(os.path.dirname(__file__), '..')
ASSETS = os.path.join(ROOT, 'mods', 'vinylgod', 'sequences', 'assets')
BACKUP = os.path.join(ROOT, 'assets_src', 'static_frames')
os.makedirs(BACKUP, exist_ok=True)

FRAMES = 6
TICK = 130  # ms per frame -> ~0.8s pulse

BUILDINGS = ['popupshop', 'pressplant', 'ampstack', 'vault', 'merchtable', 'garage',
             'mastering', 'hornpit', 'streamhub', 'datacentre', 'transcoder', 'podfarm',
             'printfarm', 'adblocker', 'algorithm', 'launchramp', 'droneport', 'waxseed',
             'lacquer']


def glow_mask(im):
    """Alpha-scaled mask of 'lit' pixels: saturated or very bright."""
    hsv = im.convert('RGB').convert('HSV')
    h, s, v = hsv.split()
    a = im.getchannel('A')
    mask = Image.new('L', im.size, 0)
    mp, sp, vp, ap = mask.load(), s.load(), v.load(), a.load()
    for y in range(im.height):
        for x in range(im.width):
            if ap[x, y] > 40 and (sp[x, y] > 130 and vp[x, y] > 110 or vp[x, y] > 225):
                mp[x, y] = ap[x, y]
    return mask


def brighten(im, factor):
    r, g, b, a = im.split()
    out = Image.merge('RGBA', tuple(ch.point(lambda p: min(255, int(p * factor))) for ch in (r, g, b)) + (a,))
    return out


def animate(name):
    src = os.path.join(ASSETS, f'{name}.png')
    if not os.path.exists(src):
        return None
    back = os.path.join(BACKUP, f'{name}.png')
    if not os.path.exists(back):
        im = Image.open(src).convert('RGBA')
        # if this is already a sheet somehow, keep frame 0
        if im.width > im.height:
            im = im.crop((0, 0, im.height, im.height))
        im.save(back)
    base = Image.open(back).convert('RGBA')
    w, h = base.size
    mask = glow_mask(base)

    sheet = Image.new('RGBA', (w * FRAMES, h), (0, 0, 0, 0))
    for i in range(FRAMES):
        t = 0.5 + 0.5 * math.sin(2 * math.pi * i / FRAMES)
        lit = brighten(base, 1.0 + 0.55 * t)
        frame = Image.composite(lit, base, mask.point(lambda p: int(p * t)))
        sheet.paste(frame, (i * w, 0))
    meta = PngInfo()
    meta.add_text('FrameSize', f'{w},{h}')
    sheet.save(src, pnginfo=meta)
    return w


def patch_sequences(done):
    p = os.path.join(ROOT, 'mods', 'vinylgod', 'sequences', 'economy.yaml')
    s = open(p).read()
    for name in done:
        # idle block: add/replace Length+Tick right after the Filename line
        pat = re.compile(
            rf'(^{name}:\n\tidle:\n\t\tFilename: sequences/assets/{name}\.png\n)(?:\t\tLength: \d+\n)?(?:\t\tTick: \d+\n)?',
            re.M)
        s = pat.sub(rf'\g<1>\t\tLength: {FRAMES}\n\t\tTick: {TICK}\n', s)
    open(p, 'w').write(s)


done = []
for b in BUILDINGS:
    if animate(b):
        done.append(b)
        print(f'animated {b}')
patch_sequences(done)
print(f'{len(done)} sprites animated, sequences patched')