# -*- coding: utf-8 -*-
"""原创离线合成样例；不连接模型、不读取账户。输出位于脚本旁。
已有输入保留，修改输入后可以重跑。失败边界由 --negative 单独演示。
"""
from pathlib import Path
import sys, json, csv, math, io, hashlib, html, base64, re
sys.stdout.reconfigure(encoding='utf-8')
sys.stderr.reconfigure(encoding='utf-8')
BASE = Path(__file__).resolve().parent
NEG = '--negative' in sys.argv
def write(name, value):
    p=BASE/name; p.parent.mkdir(parents=True,exist_ok=True)
    if isinstance(value,bytes): p.write_bytes(value)
    else: p.write_text(value,encoding='utf-8',newline='')
def seed(name,value):
    if not (BASE/name).exists(): write(name,value)
def jwrite(name,value): write(name,json.dumps(value,ensure_ascii=False,indent=2))
def jseed(name,value):
    if not (BASE/name).exists(): jwrite(name,value)
def load(name): return json.loads((BASE/name).read_text(encoding='utf-8'))
def table(name,heads,rows):
    f=io.StringIO(newline='');w=csv.writer(f);w.writerow(heads);w.writerows(rows);write(name,f.getvalue())
def page(name,title,body):
    write(name,'<!doctype html><html lang="zh-CN"><meta charset="utf-8"><meta name="viewport" content="width=device-width,initial-scale=1"><title>'+html.escape(title)+'</title><style>body{max-width:1000px;margin:2rem auto;padding:0 1rem;font:17px/1.7 system-ui}table{border-collapse:collapse}td,th{border:1px solid #aaa;padding:.5rem}pre{white-space:pre-wrap;overflow-wrap:anywhere}img,svg{max-width:100%;height:auto}a{color:#125caa}</style><h1>'+html.escape(title)+'</h1>'+body+'</html>')
def emit(data): print(json.dumps(data,ensure_ascii=False))

from PIL import Image,ImageDraw
im=Image.new('RGBA',(96,64));ImageDraw.Draw(im).ellipse((15,5,80,60),fill=(30,100,180,180));buf=io.BytesIO();im.save(buf,format='PNG');jseed('synthetic-response.json',{'fixture':'原创合成，未调用API','data':[{'b64_json':base64.b64encode(buf.getvalue()).decode()}]});d=load('synthetic-response.json');raw=base64.b64decode(d['data'][0]['b64_json'],validate=True);write('transparent.png',raw);im=Image.open(io.BytesIO(raw)).convert('RGBA')
if NEG:im.putalpha(255)
extrema=im.getchannel('A').getextrema()
if extrema==(255,255):raise ValueError('alpha全部不透明，不能当作透明交付')
for label,color in [('light','#ffffff'),('dark','#18232f')]:bg=Image.new('RGBA',im.size,color);Image.alpha_composite(bg,im).convert('RGB').save(BASE/(label+'-preview.png'))
jwrite('delivery.json',{'sha256':hashlib.sha256(raw).hexdigest(),'alpha_extrema':extrema,'format':'PNG','fixture_only':True});emit({'alpha_extrema':extrema,'size':im.size})