// Copyright (C) 2024, The Duplicati Team
// https://duplicati.com, hello@duplicati.com
// 
// Permission is hereby granted, free of charge, to any person obtaining a 
// copy of this software and associated documentation files (the "Software"), 
// to deal in the Software without restriction, including without limitation 
// the rights to use, copy, modify, merge, publish, distribute, sublicense, 
// and/or sell copies of the Software, and to permit persons to whom the 
// Software is furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in 
// all copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER 
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING 
// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 
// DEALINGS IN THE SOFTWARE.

using Duplicati.Library.Interface;

namespace Duplicati.Library.SecretProvider;

/// <summary>
/// Secret provider that reads secrets from environment variables
/// </summary>
public class EnvironmentSecretProvider : ISecretProvider
{
    /// <inheritdoc />
    public string Key => "env";

    /// <inheritdoc />
    public string DisplayName => Strings.EnvironmentSecretProvider.DisplayName;

    /// <inheritdoc />
    public string Description => Strings.EnvironmentSecretProvider.Description;

    /// <inheritdoc />
    public IList<ICommandLineArgument> SupportedCommands => [];

    /// <inheritdoc />
    public Task InitializeAsync(Uri config, CancellationToken cancellationToken)
        => Task.CompletedTask;

    /// <inheritdoc />
    public Task<Dictionary<string, string>> ResolveSecretsAsync(IEnumerable<string> keys, CancellationToken cancellationToken)
    {
        var env = Environment.GetEnvironmentVariables(EnvironmentVariableTarget.Process);
        var envLookup = env.Keys.Cast<string>().ToDictionary(k => k, k => env[k] as string, StringComparer.OrdinalIgnoreCase);
        return Task.FromResult(
            keys.ToDictionary(
                k => k,
                k =>
                {
                    var value = envLookup.GetValueOrDefault(k);
                    if (string.IsNullOrWhiteSpace(value))
                        throw new KeyNotFoundException($"The key '{k}' was not found");
                    return value;
                }
            )
        );
    }
}
