#静态文件管理：优雅地加载 CSS、JavaScript 和本地图片

# app/__init__.py
from flask import Flask

def create_app():
    app = Flask(__name__)

    # 添加额外的静态文件夹
    app.add_url_rule(
        '/media',
        endpoint='media',
        view_func=lambda: None
    )

    # 更简单的方式：
    from werkzeug.middleware.shared_data import SharedDataMiddleware
    app.wsgi_app = SharedDataMiddleware(
        app.wsgi_app,
        {"/media": "path/to/media"}
    )

    return app

# app/utils.py
import hashlib
import os

def static_url(filename):
    """生成带哈希的静态文件 URL（用于缓存控制）"""
    filepath = os.path.join(
        current_app.root_path, "static", filename
    )
    if os.path.exists(filepath):
        with open(filepath, "rb") as f:
            version = hashlib.md5(f.read()).hexdigest()[:8]
        return url_for("static", filename=filename) + f"?v={version}"
    return url_for("static", filename=filename)

# app/__init__.py
import os

app.config["MAX_CONTENT_LENGTH"] = 16 * 1024 * 1024  # 最大 16MB
app.config["ALLOWED_EXTENSIONS"] = {"png", "jpg", "jpeg", "gif", "webp"}
UPLOAD_FOLDER = os.path.join(os.path.dirname(os.path.abspath(__file__)), "static", "uploads")

def allowed_file(filename):
    return "." in filename and filename.rsplit(".", 1)[1].lower() in app.config["ALLOWED_EXTENSIONS"]

# app/routes/upload.py
from flask import Blueprint, request, redirect, url_for, flash
from werkzeug.utils import secure_filename
from flask_login import current_user
import os
import uuid

upload_bp = Blueprint("upload", __name__)

@upload_bp.route("/upload/avatar", methods=["POST"])
def upload_avatar():
    if not current_user.is_authenticated:
        return redirect(url_for("auth.login"))

    if "file" not in request.files:
        flash("没有文件！")
        return redirect(url_for("profile"))

    file = request.files["file"]
    if file.filename == "":
        flash("没有选择文件！")
        return redirect(url_for("profile"))

    if file and allowed_file(file.filename):
        # 生成安全文件名（UUID + 原扩展名）
        ext = file.filename.rsplit(".", 1)[1].lower()
        filename = f"{uuid.uuid4().hex}.{ext}"
        filepath = os.path.join(app.root_path, "static", "uploads", "avatars", filename)

        os.makedirs(os.path.dirname(filepath), exist_ok=True)
        file.save(filepath)

        # 更新用户头像
        current_user.avatar = f"/static/uploads/avatars/{filename}"
        db.session.commit()

        flash("头像上传成功！")
        return redirect(url_for("profile"))

    flash("不支持的文件类型！")
    return redirect(url_for("profile"))