screen_controller/main.py

#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
屏幕播放控制系统 - 后端服务
Screen Controller - Backend Server

一个用于展厅多屏幕定时播放控制的轻量级系统：
- 控制端（/）通过 Web 界面管理设备与播放列表
- 播放端（/player?device_id=xxx）按配置的时间定时播放图片/视频
- 支持局域网内多台设备同时访问
"""

import os
import json
from datetime import datetime

from flask import (
    Flask,
    render_template,
    request,
    jsonify,
    send_from_directory,
)
from werkzeug.utils import secure_filename

app = Flask(__name__)

# ---------------------------------------------------------------------------
# 基础配置
# ---------------------------------------------------------------------------
BASE_DIR = os.path.dirname(os.path.abspath(__file__))
CONFIG_FILE = os.path.join(BASE_DIR, "config.json")
STATIC_DIR = os.path.join(BASE_DIR, "static")
UPLOAD_DIR = STATIC_DIR  # 上传的媒体文件存放目录

# 允许上传的媒体类型（扩展名 -> 类型）
ALLOWED_EXTENSIONS = {
    "png": "image",
    "jpg": "image",
    "jpeg": "image",
    "gif": "image",
    "webp": "image",
    "bmp": "image",
    "mp4": "video",
    "webm": "video",
    "ogg": "video",
    "mov": "video",
    "avi": "video",
    "mkv": "video",
}

# 默认监听地址与端口（0.0.0.0 允许局域网访问）
HOST = os.environ.get("HOST", "0.0.0.0")
PORT = int(os.environ.get("PORT", "5000"))


# ---------------------------------------------------------------------------
# 配置读写
# ---------------------------------------------------------------------------
def load_config():
    """加载配置文件；若不存在则返回默认结构。"""
    if os.path.exists(CONFIG_FILE):
        try:
            with open(CONFIG_FILE, "r", encoding="utf-8") as f:
                data = json.load(f)
                if not isinstance(data, dict):
                    data = {}
                if "devices" not in data or not isinstance(data["devices"], list):
                    data["devices"] = []
                return data
        except (json.JSONDecodeError, OSError):
            return {"devices": []}
    return {"devices": []}


def save_config(config):
    """保存配置到文件。"""
    with open(CONFIG_FILE, "w", encoding="utf-8") as f:
        json.dump(config, f, ensure_ascii=False, indent=4)


def find_device(config, device_id):
    """在配置中查找指定 id 的设备。"""
    return next((d for d in config.get("devices", []) if d.get("id") == device_id), None)


def allowed_file(filename):
    """判断文件扩展名是否在允许列表中。"""
    return "." in filename and filename.rsplit(".", 1)[1].lower() in ALLOWED_EXTENSIONS


# ---------------------------------------------------------------------------
# 页面路由
# ---------------------------------------------------------------------------
@app.route("/")
def index():
    """控制端：设备管理页面。"""
    return render_template("index.html")


@app.route("/player")
@app.route("/player/<device_id>")
def player(device_id=None):
    """播放端页面。device_id 既可通过路径也可通过查询参数传入。"""
    return render_template("player.html")


# ---------------------------------------------------------------------------
# API：配置
# ---------------------------------------------------------------------------
@app.route("/get_config")
def get_config():
    """返回完整 JSON 配置。"""
    return jsonify(load_config())


@app.route("/save_config", methods=["POST"])
def save_config_endpoint():
    """保存完整配置（来自控制端编辑）。"""
    try:
        data = request.get_json(force=True, silent=True)
        if not isinstance(data, dict) or "devices" not in data:
            return jsonify({"status": "error", "message": "配置格式不正确"}), 400
        save_config(data)
        return jsonify({"status": "success"})
    except Exception as e:  # noqa: BLE001
        return jsonify({"status": "error", "message": str(e)}), 400


@app.route("/get_playlist/<device_id>")
def get_playlist(device_id):
    """播放端请求某个设备的播放列表。"""
    config = load_config()
    device = find_device(config, device_id)
    if not device:
        return jsonify({"error": "Device not found"}), 404
    # 按 start_time 升序返回，便于前端调度
    playlist = sorted(
        device.get("playlist", []),
        key=lambda x: x.get("start_time", ""),
    )
    return jsonify(
        {
            "device_id": device_id,
            "name": device.get("name", device_id),
            "playlist": playlist,
        }
    )


# ---------------------------------------------------------------------------
# API：媒体文件
# ---------------------------------------------------------------------------
@app.route("/upload", methods=["POST"])
def upload_file():
    """上传媒体文件到 static 目录。"""
    if "file" not in request.files:
        return jsonify({"status": "error", "message": "未找到文件字段"}), 400
    file = request.files["file"]
    if file.filename == "":
        return jsonify({"status": "error", "message": "未选择文件"}), 400
    if not allowed_file(file.filename):
        return jsonify({"status": "error", "message": "不支持的文件类型"}), 400

    filename = secure_filename(file.filename)
    # 避免重名覆盖
    base, ext = os.path.splitext(filename)
    counter = 1
    target = os.path.join(UPLOAD_DIR, filename)
    while os.path.exists(target):
        filename = f"{base}_{counter}{ext}"
        target = os.path.join(UPLOAD_DIR, filename)
        counter += 1

    file.save(target)
    media_type = ALLOWED_EXTENSIONS[filename.rsplit(".", 1)[1].lower()]
    return jsonify(
        {
            "status": "success",
            "filename": filename,
            "path": f"/static/{filename}",
            "type": media_type,
        }
    )


@app.route("/files")
def list_files():
    """列出 static 目录下可用的媒体文件。"""
    files = []
    if os.path.isdir(STATIC_DIR):
        for name in sorted(os.listdir(STATIC_DIR)):
            ext = name.rsplit(".", 1)[-1].lower() if "." in name else ""
            if ext in ALLOWED_EXTENSIONS:
                files.append({"name": name, "path": f"/static/{name}", "type": ALLOWED_EXTENSIONS[ext]})
    return jsonify({"files": files})


@app.route("/static/<path:filename>")
def serve_static(filename):
    """提供静态媒体文件访问。"""
    return send_from_directory(STATIC_DIR, filename)


if __name__ == "__main__":
    os.makedirs(STATIC_DIR, exist_ok=True)
    # 关闭 debug 以避免生产环境安全隐患；可通过环境变量 FLASK_DEBUG=1 开启
    debug = os.environ.get("FLASK_DEBUG", "0") == "1"
    print(f"屏幕控制系统已启动： http://{HOST}:{PORT}/  (局域网内其他设备可访问)")
    app.run(host=HOST, port=PORT, debug=debug)