using Admin.NET.Plugin.AiDOP.Service.S8;
using System.Text.RegularExpressions;
using Xunit;

namespace Admin.NET.Plugin.AiDOP.Tests.S8;

public class S8HomeAlertQueryServiceTests
{
    private static readonly DateTime Now = new(2026, 9, 30, 12, 0, 0);

    [Fact]
    public void SeriousOutranksFollow()
    {
        var decision = S8ModuleLampPolicy.Decide(1, 4, new[] { Healthy() }, Now);

        Assert.Equal("CRITICAL", decision.BusinessState);
        Assert.Equal("HEALTHY", decision.MonitorState);
    }

    [Fact]
    public void SeriousOpenException_StaysRedWhenRuleIsDisabled()
    {
        var decision = S8ModuleLampPolicy.Decide(1, 0, new[] { Rule(enabled: false) }, Now);

        Assert.Equal("CRITICAL", decision.BusinessState);
        Assert.Equal("PAUSED", decision.MonitorState);
        Assert.Equal("RULE_DISABLED", decision.MonitorReasonCode);
    }

    [Fact]
    public void FollowOnly_IsWarningWhileMonitorStaysHealthy()
    {
        var decision = S8ModuleLampPolicy.Decide(0, 2, new[] { Healthy() }, Now);

        Assert.Equal("WARNING", decision.BusinessState);
        Assert.Equal("HEALTHY", decision.MonitorState);
        Assert.Equal("OK", decision.MonitorReasonCode);
    }

    [Fact]
    public void GreenRequiresHealthyMonitorAndZeroOpenExceptions()
    {
        var decision = S8ModuleLampPolicy.Decide(0, 0, new[] { Healthy() }, Now);

        Assert.Equal("NORMAL", decision.BusinessState);
        Assert.Equal("HEALTHY", decision.MonitorState);
    }

    [Fact]
    public void UnmonitoredModule_IsUnknown_NotGreen()
    {
        var decision = S8ModuleLampPolicy.Decide(0, 0, Array.Empty<S8WatchRuleSignal>(), Now);

        Assert.Equal("UNKNOWN", decision.BusinessState);
        Assert.Equal("UNMONITORED", decision.MonitorState);
        Assert.Equal("NO_RULE", decision.MonitorReasonCode);
    }

    [Fact]
    public void StaleRunnableRule_IsDegraded_AndDoesNotTurnGreen()
    {
        var decision = S8ModuleLampPolicy.Decide(0, 0, new[] { Healthy(Now.AddMinutes(-11)) }, Now);

        Assert.Equal("UNKNOWN", decision.BusinessState);
        Assert.Equal("DEGRADED", decision.MonitorState);
        Assert.Equal("RUN_STALE", decision.MonitorReasonCode);
    }

    [Fact]
    public void FailedRun_OutranksStaleAndNeverRun()
    {
        var rules = new[]
        {
            Healthy(Now.AddHours(-2)),
            Rule(enabled: true, lastStatus: "FAILED", lastRunAt: Now.AddMinutes(-1))
        };

        var decision = S8ModuleLampPolicy.Decide(0, 0, rules, Now);

        Assert.Equal("DEGRADED", decision.MonitorState);
        Assert.Equal("RUN_FAILED", decision.MonitorReasonCode);
    }

    [Fact]
    public void NeverRun_IsDegraded()
    {
        var decision = S8ModuleLampPolicy.Decide(0, 0, new[] { Rule(enabled: true) }, Now);

        Assert.Equal("DEGRADED", decision.MonitorState);
        Assert.Equal("NEVER_RUN", decision.MonitorReasonCode);
    }

    [Fact]
    public void EnabledRulePausedUntilFuture_IsPausedNotUnmonitored()
    {
        var decision = S8ModuleLampPolicy.Decide(
            3, 0, new[] { Rule(enabled: true, pausedUntil: Now.AddHours(1), lastStatus: "SUCCESS", lastRunAt: Now) }, Now);

        Assert.Equal("CRITICAL", decision.BusinessState);
        Assert.Equal("PAUSED", decision.MonitorState);
        Assert.Equal("RULE_PAUSED", decision.MonitorReasonCode);
    }

    [Fact]
    public void OneHealthyRunnableRule_IgnoresASiblingPausedRule()
    {
        var rules = new[]
        {
            Healthy(),
            Rule(enabled: true, pausedUntil: Now.AddHours(1))
        };

        var decision = S8ModuleLampPolicy.Decide(0, 0, rules, Now);

        Assert.Equal("NORMAL", decision.BusinessState);
        Assert.Equal("HEALTHY", decision.MonitorState);
    }

    [Fact]
    public void FreshWindow_IsAtLeastTenMinutes()
    {
        Assert.Equal(600, S8ModuleLampPolicy.FreshWindowSeconds(30));
        Assert.Equal(800, S8ModuleLampPolicy.FreshWindowSeconds(400));
    }

    [Fact]
    public void TrendCountsCreatedAt_AndDoesNotUseLastDetectedAt()
    {
        var code = ReadService();
        var trend = MethodBody(code, "public async Task<List<S8HomeTrendPoint>> GetCreatedTrendAsync");
        var summary = MethodBody(code, "public async Task<S8HomeAlertSummary> GetCreatedSummaryAsync");

        Assert.Contains("DATE(created_at)", trend);
        Assert.DoesNotContain("last_detected_at", trend);
        Assert.DoesNotContain("status NOT IN", summary);
        Assert.DoesNotContain("factory_id", trend);
        Assert.Contains("ado_s8_watch_rule", code);
        var lamps = MethodBody(code, "public async Task<S8ModuleLampPayload> GetModuleLampsAsync");
        Assert.Contains("status NOT IN ('CLOSED','REJECTED','RECOVERED')", lamps);
        Assert.Contains("S8ModuleCode.All", lamps);
        Assert.DoesNotContain("DateTime.Now", lamps);
        var endpoint = MethodBody(ReadController(), "public async Task<IActionResult> GetS8ModuleLamps");
        Assert.Contains("[HttpGet(\"s8-module-lamps\")]", ReadController());
        Assert.Contains("AidopTenantHelper.GetTenantId(HttpContext)", endpoint);
        Assert.DoesNotContain("[FromQuery]", endpoint);
        Assert.DoesNotContain("factoryId", endpoint);
        foreach (var signature in new[]
        {
            "public async Task<IActionResult> GetS8Alerts",
            "public async Task<IActionResult> GetS8AlertSummary",
            "public async Task<IActionResult> GetS8HomeTrend"
        })
        {
            Assert.DoesNotContain("ado_s8_alert_record", MethodBody(ReadController(), signature));
        }
    }

    private static S8WatchRuleSignal Healthy(DateTime? lastRunAt = null) =>
        Rule(enabled: true, lastStatus: "SUCCESS", lastRunAt: lastRunAt ?? Now.AddMinutes(-1));

    private static S8WatchRuleSignal Rule(
        bool enabled,
        string? lastStatus = null,
        DateTime? lastRunAt = null,
        DateTime? pausedUntil = null) =>
        new("S1", enabled, 300, lastStatus, lastRunAt, pausedUntil);

    private static string ReadService() => Strip(Path.Combine(PluginRoot, "Service/S8/S8HomeAlertQueryService.cs"));
    private static string ReadController() => Strip(Path.Combine(PluginRoot, "Controllers/AidopKanbanController.cs"));

    private static string PluginRoot => Path.GetFullPath(
        Path.Combine(AppContext.BaseDirectory, "../../../../Admin.NET.Plugin.AiDOP"));

    private static string Strip(string path)
    {
        var raw = File.ReadAllText(path);
        var noBlock = Regex.Replace(raw, @"/\*.*?\*/", string.Empty, RegexOptions.Singleline);
        return Regex.Replace(noBlock, @"^\s*//.*$", string.Empty, RegexOptions.Multiline);
    }

    private static string MethodBody(string code, string signature)
    {
        var start = code.IndexOf(signature, StringComparison.Ordinal);
        Assert.True(start > 0, signature);
        var from = start + signature.Length;
        var end = code.Length;
        foreach (var kw in new[] { "\n    public ", "\n    private ", "\n    internal ", "\n    protected " })
        {
            var i = code.IndexOf(kw, from, StringComparison.Ordinal);
            if (i > 0 && i < end) end = i;
        }
        return code[start..end];
    }
}