// -----------------------------------------------------------------------------
// Azure RG Smart Janitor - Enhanced Cleanup Tool
// Run with:   dotnet run smart-cleanup.cs
// Targets:    .NET 10 Preview 4+
// -----------------------------------------------------------------------------

#:package Azure.Identity@1.*
#:package Azure.ResourceManager@1.*
#:package Azure.ResourceManager.Compute@1.*
#:package Azure.ResourceManager.Storage@1.*
#:package Azure.ResourceManager.Sql@1.*
#:package Spectre.Console@0.50.0

using Azure.Identity;
using Azure.ResourceManager;
using Azure.ResourceManager.Resources;
using Azure.ResourceManager.Compute;
using Azure.ResourceManager.Storage;
using Azure.ResourceManager.Sql;
using Spectre.Console;
using System.Text.RegularExpressions;

// ─────────────── Settings ─────────────────────────────────────────────────────
const int MaxParallel = 5;                // Reduced for safety
const int StaleAgeDays = 30;              // Consider RGs older than this as potentially stale
const int EmptyResourceThreshold = 3;     // RGs with <= this many resources are candidates
// ──────────────────────────────────────────────────────────────────────────────

// 1️⃣ Select subscription
var arm = new ArmClient(new DefaultAzureCredential());
var subList = new List<SubscriptionResource>();

await AnsiConsole.Status()
    .Spinner(Spinner.Known.Dots)
    .SpinnerStyle(Style.Parse("yellow"))
    .StartAsync("Fetching Azure subscriptions...", async ctx =>
    {
        await foreach (var s in arm.GetSubscriptions())
            subList.Add(s);
    });

if (subList.Count == 0)
{
    AnsiConsole.MarkupLine("[red]❌ No subscriptions found.[/]");
    return;
}

var subChoices = subList.Select(s => $"{s.Data.DisplayName} ({s.Data.SubscriptionId})").ToList();
subChoices.Add("Cancel");
var selectedSub = AnsiConsole.Prompt(
    new SelectionPrompt<string>()
        .Title("Select an Azure subscription:")
        .AddChoices(subChoices)
        .PageSize(10)
        .MoreChoicesText("[grey](Move up and down to reveal more subscriptions)[/]")
        .HighlightStyle("blue")
        .EnableSearch()
);

if (selectedSub == "Cancel")
{
    AnsiConsole.MarkupLine("[red]❌ Aborted by user.[/]");
    return;
}

var subIdx = subChoices.IndexOf(selectedSub);
var sub = subList[subIdx];

AnsiConsole.MarkupLine($"[bold blue]🔍 Analyzing subscription [yellow]{sub.Data.DisplayName}[/]…[/]");

// Helper function to analyze a resource group
async Task<RgInfo> AnalyzeResourceGroup(ResourceGroupResource rg)
{
    var resources = new List<string>();
    var resourceTypes = new List<string>();
    var hasRunningVMs = false;
    var hasDatabases = false;
    var hasProductionIndicators = false;
    DateTime? lastModified = null;

    try
    {
        // Get all resources in the RG - Fixed: removed GetAll() as Pageable<T> is already IEnumerable
        var genericResources = rg.GetGenericResources();
        foreach (var resource in genericResources)
        {
            resources.Add(resource.Data.Name);
            var resourceType = resource.Data.ResourceType.Type;
            if (!resourceTypes.Contains(resourceType))
                resourceTypes.Add(resourceType);

            // Check for running VMs
            if (resourceType == "virtualMachines")
            {
                try
                {
                    var vmResource = await rg.GetVirtualMachines().GetAsync(resource.Data.Name);
                    if (vmResource.Value.Data.InstanceView?.Statuses?.Any(s => 
                        s.Code?.Contains("PowerState/running") == true) == true)
                    {
                        hasRunningVMs = true;
                    }
                }
                catch { /* Ignore access errors */ }
            }

            // Check for databases
            if (resourceType == "servers" || resourceType == "databases" || 
                resourceType == "sqlServers" || resourceType == "managedInstances")
            {
                hasDatabases = true;
            }

            // Update last modified
            if (resource.Data.CreatedOn.HasValue && 
                (!lastModified.HasValue || resource.Data.CreatedOn.Value.DateTime > lastModified))
            {
                lastModified = resource.Data.CreatedOn.Value.DateTime;
            }
        }
    }
    catch
    {
        // If we can't enumerate resources, be conservative
        hasProductionIndicators = true;
    }

    // Check for production indicators
    var rgName = rg.Data.Name.ToLowerInvariant();
    var tags = rg.Data.Tags ?? new Dictionary<string, string>();
    
    hasProductionIndicators = hasProductionIndicators ||
        rgName.Contains("prod") ||
        rgName.Contains("production") ||
        tags.Any(t => t.Key.ToLowerInvariant().Contains("env") && 
                     t.Value.ToLowerInvariant().Contains("prod")) ||
        tags.Any(t => t.Value.ToLowerInvariant().Contains("production"));

    // Check if it matches test patterns
    var testPatterns = new[] { "test", "demo", "poc", "temp", "sandbox", "dev", "experiment", "trial", "sample" };
    var matchesTestPattern = testPatterns.Any(pattern => rgName.Contains(pattern)) ||
        tags.Any(t => testPatterns.Any(p => t.Value.ToLowerInvariant().Contains(p)));

    // Determine risk level
    var riskLevel = "HIGH"; // Default to high risk
    
    if (!hasRunningVMs && !hasDatabases && !hasProductionIndicators)
    {
        if (matchesTestPattern || resources.Count <= EmptyResourceThreshold)
            riskLevel = "LOW";
        else if (lastModified.HasValue && (DateTime.UtcNow - lastModified.Value).Days > StaleAgeDays)
            riskLevel = "MEDIUM";
        else
            riskLevel = "MEDIUM";
    }

    return new RgInfo(
        rg,
        resources.Count,
        hasRunningVMs,
        hasDatabases,
        hasProductionIndicators,
        matchesTestPattern,
        lastModified,
        riskLevel,
        resourceTypes
    );
}

// 2️⃣ Analyze all resource groups intelligently
var allRgs = new List<RgInfo>();
var analyzed = 0;

await AnsiConsole.Progress()
    .AutoClear(false)
    .Columns(
    [
        new TaskDescriptionColumn(),
        new ProgressBarColumn(),
        new SpinnerColumn(),
        new ElapsedTimeColumn(),
    ])
    .StartAsync(async ctx =>
    {
        var rgList = new List<ResourceGroupResource>();
        // Fixed: removed GetAll() as Pageable<T> is already IEnumerable
        foreach (var rg in sub.GetResourceGroups())
            rgList.Add(rg);

        var analysisTask = ctx.AddTask($"[blue]Analyzing resource groups[/]", maxValue: rgList.Count);

        foreach (var rg in rgList)
        {
            try
            {
                analysisTask.Description = $"[blue]Analyzing[/] [yellow]{rg.Data.Name}[/]";
                var rgInfo = await AnalyzeResourceGroup(rg);
                allRgs.Add(rgInfo);
                analyzed++;
            }
            catch (Exception ex)
            {
                AnsiConsole.MarkupLine($"[red]⚠ Error analyzing {rg.Data.Name}: {ex.Message}[/]");
            }
            analysisTask.Increment(1);
        }
    });

AnsiConsole.MarkupLine($"[green]✅ Analyzed {analyzed} resource groups[/]");

// 3️⃣ Filter for cleanup candidates
var cleanupCandidates = allRgs.Where(rg => 
    rg.RiskLevel == "LOW" || rg.RiskLevel == "MEDIUM"
).OrderBy(rg => rg.RiskLevel)
  .ThenBy(rg => rg.ResourceGroup.Data.Name, StringComparer.OrdinalIgnoreCase)
  .ToList();

if (cleanupCandidates.Count == 0)
{
    AnsiConsole.MarkupLine("[green]✔ No cleanup candidates found. Your subscription looks clean![/]");
    
    // Show summary of what was excluded
    var excluded = allRgs.Where(rg => rg.RiskLevel == "HIGH").ToList();
    if (excluded.Count > 0)
    {
        AnsiConsole.MarkupLine($"\n[yellow]ℹ {excluded.Count} resource groups were excluded due to production indicators:[/]");
        foreach (var rg in excluded.Take(5))
            AnsiConsole.MarkupLine($"  • [yellow]{rg.ResourceGroup.Data.Name}[/] - {rg.ResourceTypes.Count} resources");
        if (excluded.Count > 5)
            AnsiConsole.MarkupLine($"  • [grey]... and {excluded.Count - 5} more[/]");
    }
    return;
}

// 4️⃣ Display cleanup candidates in a detailed table
var table = new Table()
    .Border(TableBorder.Rounded)
    .AddColumn("Risk")
    .AddColumn("Name")
    .AddColumn("Resources")
    .AddColumn("Age")
    .AddColumn("Patterns")
    .AddColumn("Details");

foreach (var rg in cleanupCandidates)
{
    var riskColor = rg.RiskLevel switch
    {
        "LOW" => "green",
        "MEDIUM" => "yellow",
        _ => "red"
    };
    
    var ageText = rg.LastModified?.ToString("yyyy-MM-dd") ?? "Unknown";
    var ageDays = rg.LastModified.HasValue ? (DateTime.UtcNow - rg.LastModified.Value).Days : 0;
    if (ageDays > StaleAgeDays)
        ageText += $" ([red]{ageDays}d[/])";
    
    var patterns = new List<string>();
    if (rg.MatchesTestPattern) patterns.Add("Test name");
    if (rg.ResourceCount <= EmptyResourceThreshold) patterns.Add("Few resources");
    if (!rg.HasRunningVMs && !rg.HasDatabases) patterns.Add("No critical services");
    
    var details = string.Join(", ", rg.ResourceTypes.Take(3));
    if (rg.ResourceTypes.Count > 3)
        details += $", +{rg.ResourceTypes.Count - 3} more";

    table.AddRow(
        $"[{riskColor}]{rg.RiskLevel}[/]",
        rg.ResourceGroup.Data.Name,
        rg.ResourceCount.ToString(),
        ageText,
        string.Join(", ", patterns),
        details
    );
}

AnsiConsole.Write(table);

// 5️⃣ Show totals and options
AnsiConsole.MarkupLine($"\n[bold]Summary:[/]");
AnsiConsole.MarkupLine($"  • [green]{cleanupCandidates.Count(c => c.RiskLevel == "LOW")}[/] low-risk candidates");
AnsiConsole.MarkupLine($"  • [yellow]{cleanupCandidates.Count(c => c.RiskLevel == "MEDIUM")}[/] medium-risk candidates");
AnsiConsole.MarkupLine($"  • [red]{allRgs.Count(rg => rg.RiskLevel == "HIGH")}[/] high-risk (excluded)");

// 6️⃣ Dry run option
var mode = AnsiConsole.Prompt(
    new SelectionPrompt<string>()
        .Title("What would you like to do?")
        .AddChoices([
            "Dry run - Show what would be deleted",
            "Select specific resource groups to delete",
            "Auto-delete only LOW risk items",
            "Cancel"
        ])
        .HighlightStyle("blue")
);

if (mode == "Cancel")
{
    AnsiConsole.MarkupLine("[red]❌ Aborted by user.[/]");
    return;
}

List<RgInfo> toDelete = [];

if (mode == "Dry run - Show what would be deleted")
{
    toDelete = cleanupCandidates.Where(c => c.RiskLevel == "LOW").ToList();
    AnsiConsole.MarkupLine($"\n[bold blue]🔍 DRY RUN - Would delete {toDelete.Count} low-risk resource groups:[/]");
    foreach (var rg in toDelete)
    {
        AnsiConsole.MarkupLine($"  • [yellow]{rg.ResourceGroup.Data.Name}[/]");
        AnsiConsole.MarkupLine($"    - {rg.ResourceCount} resources: {string.Join(", ", rg.ResourceTypes)}");
    }
    AnsiConsole.MarkupLine("\n[grey]No actual deletions performed.[/]");
    return;
}
else if (mode == "Auto-delete only LOW risk items")
{
    toDelete = cleanupCandidates.Where(c => c.RiskLevel == "LOW").ToList();
}
else if (mode == "Select specific resource groups to delete")
{
    var rgChoices = cleanupCandidates.Select(rg => 
        $"{rg.ResourceGroup.Data.Name} ({rg.RiskLevel} risk - {rg.ResourceCount} resources)"
    ).ToList();
    
    if (rgChoices.Count == 0)
    {
        AnsiConsole.MarkupLine("[yellow]No candidates available for selection.[/]");
        return;
    }

    var selectedRgNames = AnsiConsole.Prompt(
        new MultiSelectionPrompt<string>()
            .Title("Select resource groups to delete:")
            .NotRequired()
            .PageSize(15)
            .InstructionsText("[grey](Press [blue]<space>[/] to toggle, [green]<enter>[/] to accept)[/]")
            .AddChoices(rgChoices)
    );

    if (selectedRgNames.Count == 0)
    {
        AnsiConsole.MarkupLine("[red]❌ Nothing selected.[/]");
        return;
    }

    toDelete = cleanupCandidates.Where(rg => 
        selectedRgNames.Any(s => s.StartsWith(rg.ResourceGroup.Data.Name + " ("))
    ).ToList();
}

if (toDelete.Count == 0)
{
    AnsiConsole.MarkupLine("[yellow]No resource groups to delete.[/]");
    return;
}

// 7️⃣ Final confirmation with detailed breakdown
AnsiConsole.MarkupLine($"\n[bold red]⚠ DELETION CONFIRMATION[/]");
AnsiConsole.MarkupLine($"About to delete [yellow]{toDelete.Count}[/] resource groups:");

foreach (var rg in toDelete)
{
    AnsiConsole.MarkupLine($"  • [yellow]{rg.ResourceGroup.Data.Name}[/] ([{(rg.RiskLevel == "LOW" ? "green" : "yellow")}]{rg.RiskLevel}[/] risk)");
}

var finalConfirm = AnsiConsole.Confirm(
    $"\n[bold]Are you absolutely sure you want to delete these {toDelete.Count} resource groups?[/]", 
    defaultValue: false
);

if (!finalConfirm)
{
    AnsiConsole.MarkupLine("[red]❌ Aborted.[/]");
    return;
}

// 8️⃣ Execute deletions with enhanced progress tracking
AnsiConsole.MarkupLine("[bold]🗑 Deleting resource groups...[/]");

using var gate = new SemaphoreSlim(MaxParallel);
var successCount = 0;
var failureCount = 0;

await AnsiConsole.Progress()
    .AutoClear(false)
    .Columns(
    [
        new TaskDescriptionColumn(),
        new ProgressBarColumn(),
        new SpinnerColumn(),
        new ElapsedTimeColumn(),
    ])
    .StartAsync(async ctx =>
    {
        var overallTask = ctx.AddTask("Overall progress", maxValue: toDelete.Count);
        var rgTasks = toDelete.ToDictionary(
            rg => rg.ResourceGroup.Data.Name,
            rg => ctx.AddTask($"[grey]Deleting:[/] [yellow]{rg.ResourceGroup.Data.Name}[/]", maxValue: 1)
        );

        var deleteTasks = toDelete.Select(async rgInfo =>
        {
            await gate.WaitAsync();
            try
            {
                var rgTask = rgTasks[rgInfo.ResourceGroup.Data.Name];
                rgTask.Increment(0.3);
                
                await rgInfo.ResourceGroup.DeleteAsync(Azure.WaitUntil.Completed);
                
                rgTask.Value = 1;
                rgTask.Description = $"[green]✅ Deleted:[/] [yellow]{rgInfo.ResourceGroup.Data.Name}[/]";
                Interlocked.Increment(ref successCount);
            }
            catch (Exception ex)
            {
                var rgTask = rgTasks[rgInfo.ResourceGroup.Data.Name];
                rgTask.Description = $"[red]❌ Failed:[/] [yellow]{rgInfo.ResourceGroup.Data.Name}[/] - {ex.Message}";
                Interlocked.Increment(ref failureCount);
            }
            finally
            {
                gate.Release();
                overallTask.Increment(1);
            }
        });

        await Task.WhenAll(deleteTasks);
    });

// 9️⃣ Final results
AnsiConsole.MarkupLine($"\n[bold]Cleanup Results:[/]");
AnsiConsole.MarkupLine($"  • [green]✅ Successfully deleted: {successCount}[/]");
if (failureCount > 0)
    AnsiConsole.MarkupLine($"  • [red]❌ Failed to delete: {failureCount}[/]");

AnsiConsole.MarkupLine("[bold green]🎉 Cleanup completed![/]");

// ═══════════════════════════════════════════════════════════════════════════════
// Type definitions (must be at the end with top-level statements)
// ═══════════════════════════════════════════════════════════════════════════════

// Enhanced resource group info
public record RgInfo(
    ResourceGroupResource ResourceGroup,
    int ResourceCount,
    bool HasRunningVMs,
    bool HasDatabases,
    bool HasProductionIndicators,
    bool MatchesTestPattern,
    DateTime? LastModified,
    string RiskLevel,
    List<string> ResourceTypes
);