using System;
using System.Collections.Generic;
using System.Threading;
using System.Threading.Tasks;
using StellaOps.Notify.Engine;
using StellaOps.Notify.Models;
using Xunit;

namespace StellaOps.Notify.Connectors.Slack.Tests;

public sealed class SlackChannelHealthProviderTests
{
    private static readonly SlackChannelHealthProvider Provider = new();

    [Fact]
    public async Task CheckAsync_ReturnsHealthy()
    {
        var channel = CreateChannel(enabled: true, target: "#sec-ops");

        var context = new ChannelHealthContext(
            channel.TenantId,
            channel,
            channel.Config.Target!,
            new DateTimeOffset(2025, 10, 20, 14, 0, 0, TimeSpan.Zero),
            "trace-slack-001");

        var result = await Provider.CheckAsync(context, CancellationToken.None);

        Assert.Equal(ChannelHealthStatus.Healthy, result.Status);
        Assert.Equal("true", result.Metadata["slack.channel.enabled"]);
        Assert.Equal("true", result.Metadata["slack.validation.targetPresent"]);
        Assert.Equal("#sec-ops", result.Metadata["slack.channel"]);
        Assert.Equal(ComputeSecretHash(channel.Config.SecretRef), result.Metadata["slack.secretRef.hash"]);
    }

    [Fact]
    public async Task CheckAsync_ReturnsDegradedWhenDisabled()
    {
        var channel = CreateChannel(enabled: false, target: "#sec-ops");

        var context = new ChannelHealthContext(
            channel.TenantId,
            channel,
            channel.Config.Target!,
            DateTimeOffset.UtcNow,
            "trace-slack-002");

        var result = await Provider.CheckAsync(context, CancellationToken.None);

        Assert.Equal(ChannelHealthStatus.Degraded, result.Status);
        Assert.Equal("false", result.Metadata["slack.channel.enabled"]);
    }

    [Fact]
    public async Task CheckAsync_ReturnsUnhealthyWhenTargetMissing()
    {
        var channel = CreateChannel(enabled: true, target: null);

        var context = new ChannelHealthContext(
            channel.TenantId,
            channel,
            channel.Name,
            DateTimeOffset.UtcNow,
            "trace-slack-003");

        var result = await Provider.CheckAsync(context, CancellationToken.None);

        Assert.Equal(ChannelHealthStatus.Unhealthy, result.Status);
        Assert.Equal("false", result.Metadata["slack.validation.targetPresent"]);
    }

    private static NotifyChannel CreateChannel(bool enabled, string? target)
    {
        return NotifyChannel.Create(
            channelId: "channel-slack-sec-ops",
            tenantId: "tenant-sec",
            name: "slack:sec-ops",
            type: NotifyChannelType.Slack,
            config: NotifyChannelConfig.Create(
                secretRef: "ref://notify/channels/slack/sec-ops",
                target: target,
                properties: new Dictionary<string, string>
                {
                    ["workspace"] = "stellaops-sec",
                    ["botToken"] = "xoxb-123456789012-abcdefghijklmnop"
                }),
            enabled: enabled);
    }

    private static string ComputeSecretHash(string secretRef)
    {
        var bytes = System.Text.Encoding.UTF8.GetBytes(secretRef.Trim());
        var hash = System.Security.Cryptography.SHA256.HashData(bytes);
        return Convert.ToHexString(hash.AsSpan(0, 8)).ToLowerInvariant();
    }
}