using ControlPlane.Core.Interfaces;
using ControlPlane.Core.Models;
using System.Text.Json;

namespace ControlPlane.Worker.Steps;

public class VaultStep(ILogger<VaultStep> logger, IConfiguration config) : ISagaStep
{
    public string StepName => "Cryptographic Pre-Flight (Vault)";

    public Task ExecuteAsync(SagaContext context, CancellationToken cancellationToken)
    {
        // TODO: VaultSharp
        // 1. Assert Transit engine is active and healthy
        // 2. Derive/validate TenantContextId (e.g. FL_COM_001)
        // 3. Register TenantContextId in a KV entry or TenantRegistry table
        //    so Clarity.Server can resolve the derivation path later
        //
        // Root token is read at runtime from the persisted init.json on the Vault volume:
        //   var token = ReadRootToken();
        logger.LogInformation("[{JobId}] Vault step is a stub - VaultSharp not yet wired.", context.Job.Id);
        context.Job.CompletedSteps |= CompletedSteps.VaultVerified;
        return Task.CompletedTask;
    }

    public Task CompensateAsync(SagaContext context, CancellationToken cancellationToken)
    {
        logger.LogInformation("[{JobId}] Vault step: no compensation needed.", context.Job.Id);
        return Task.CompletedTask;
    }

    /// <summary>
    /// Reads the root token from the init.json written by the Vault entrypoint on first boot.
    /// Path is injected via Vault__KeysFile config.
    /// </summary>
    internal string ReadRootToken()
    {
        var path = config["Vault__KeysFile"]
            ?? throw new InvalidOperationException("Vault__KeysFile is not configured.");

        using var doc = JsonDocument.Parse(File.ReadAllText(path));
        return doc.RootElement.GetProperty("root_token").GetString()
            ?? throw new InvalidOperationException("root_token not found in Vault init.json.");
    }
}