import os
from typing import Dict

from dotenv import load_dotenv
from flask import Flask, jsonify, render_template, request

from aws_service import (
    AWSOperationError,
    ConfigError,
    AccountConfig,
    load_account_configs,
    replace_instance_ip,
)
from db import init_db, load_disallowed_ips


load_dotenv()

app = Flask(__name__)


def load_configs() -> Dict[str, AccountConfig]:
    config_path = os.getenv("AWS_CONFIG_PATH", "config/accounts.yaml")
    return load_account_configs(config_path)


try:
    account_configs = load_configs()
    init_error = ""
except ConfigError as exc:
    account_configs = {}
    init_error = str(exc)

retry_limit = int(os.getenv("IP_RETRY_LIMIT", "5"))

try:
    init_db()
    db_error = ""
except Exception as exc:  # noqa: BLE001 - surface DB connection issues to UI
    db_error = f"数据库初始化失败: {exc}"


@app.route("/", methods=["GET"])
def index():
    if init_error or db_error:
        return render_template("index.html", accounts=[], init_error=init_error or db_error)
    return render_template("index.html", accounts=account_configs.values(), init_error="")


@app.route("/replace_ip", methods=["POST"])
def replace_ip():
    if init_error or db_error:
        return jsonify({"error": init_error or db_error}), 500

    ip_to_replace = request.form.get("ip_to_replace", "").strip()
    account_name = request.form.get("account_name", "").strip()

    if not ip_to_replace:
        return jsonify({"error": "请输入要替换的IP"}), 400
    if account_name not in account_configs:
        return jsonify({"error": "无效的账户选择"}), 400

    disallowed = load_disallowed_ips()
    account = account_configs[account_name]
    try:
        result = replace_instance_ip(ip_to_replace, account, disallowed, retry_limit)
    except AWSOperationError as exc:
        return jsonify({"error": str(exc)}), 400

    return jsonify(result), 200


if __name__ == "__main__":
    app.run(host="0.0.0.0", port=5000, debug=True)