using System.Diagnostics;
using Microsoft.Extensions.Logging;
using Microsoft.Extensions.Options;
using OTSSignsOrchestrator.Core.Configuration;
using OTSSignsOrchestrator.Core.Models.DTOs;
using OTSSignsOrchestrator.Core.Models.Entities;
using OTSSignsOrchestrator.Core.Services;

namespace OTSSignsOrchestrator.Desktop.Services;

/// <summary>
/// Docker CLI service that executes docker commands on a remote host over SSH.
/// Requires an SshHost to be set before use via SetHost().
/// </summary>
public class SshDockerCliService : IDockerCliService
{
    private readonly SshConnectionService _ssh;
    private readonly DockerOptions _options;
    private readonly ILogger<SshDockerCliService> _logger;
    private SshHost? _currentHost;

    public SshDockerCliService(
        SshConnectionService ssh,
        IOptions<DockerOptions> options,
        ILogger<SshDockerCliService> logger)
    {
        _ssh = ssh;
        _options = options.Value;
        _logger = logger;
    }

    /// <summary>
    /// Set the SSH host to use for Docker commands.
    /// </summary>
    public void SetHost(SshHost host)
    {
        _currentHost = host;
    }

    public SshHost? CurrentHost => _currentHost;

    public async Task<DeploymentResultDto> DeployStackAsync(string stackName, string composeYaml, bool resolveImage = false)
    {
        EnsureHost();
        var sw = Stopwatch.StartNew();

        var args = "docker stack deploy --compose-file -";
        if (resolveImage)
            args += " --resolve-image changed";
        args += $" {stackName}";

        _logger.LogInformation("Deploying stack via SSH: {StackName} on {Host}", stackName, _currentHost!.Label);

        var (exitCode, stdout, stderr) = await _ssh.RunCommandWithStdinAsync(_currentHost, args, composeYaml);
        sw.Stop();

        var result = new DeploymentResultDto
        {
            StackName = stackName,
            Success = exitCode == 0,
            ExitCode = exitCode,
            Output = stdout,
            ErrorMessage = stderr,
            Message = exitCode == 0 ? "Success" : "Failed",
            DurationMs = sw.ElapsedMilliseconds
        };

        if (result.Success)
            _logger.LogInformation("Stack deployed via SSH: {StackName} | duration={DurationMs}ms", stackName, result.DurationMs);
        else
            _logger.LogError("Stack deploy failed via SSH: {StackName} | error={Error}", stackName, result.ErrorMessage);

        return result;
    }

    public async Task<DeploymentResultDto> RemoveStackAsync(string stackName)
    {
        EnsureHost();
        var sw = Stopwatch.StartNew();

        _logger.LogInformation("Removing stack via SSH: {StackName} on {Host}", stackName, _currentHost!.Label);

        var (exitCode, stdout, stderr) = await _ssh.RunCommandAsync(_currentHost, $"docker stack rm {stackName}");
        sw.Stop();

        var result = new DeploymentResultDto
        {
            StackName = stackName,
            Success = exitCode == 0,
            ExitCode = exitCode,
            Output = stdout,
            ErrorMessage = stderr,
            Message = exitCode == 0 ? "Success" : "Failed",
            DurationMs = sw.ElapsedMilliseconds
        };

        if (result.Success)
            _logger.LogInformation("Stack removed via SSH: {StackName}", stackName);
        else
            _logger.LogError("Stack remove failed via SSH: {StackName} | error={Error}", stackName, result.ErrorMessage);

        return result;
    }

    public async Task<List<StackInfo>> ListStacksAsync()
    {
        EnsureHost();

        var (exitCode, stdout, _) = await _ssh.RunCommandAsync(
            _currentHost!, "docker stack ls --format '{{.Name}}\\t{{.Services}}'");

        if (exitCode != 0 || string.IsNullOrWhiteSpace(stdout))
            return new List<StackInfo>();

        return stdout
            .Split('\n', StringSplitOptions.RemoveEmptyEntries)
            .Select(line =>
            {
                var parts = line.Split('\t', 2);
                return new StackInfo
                {
                    Name = parts[0].Trim(),
                    ServiceCount = parts.Length > 1 && int.TryParse(parts[1].Trim(), out var c) ? c : 0
                };
            })
            .ToList();
    }

    public async Task<List<ServiceInfo>> InspectStackServicesAsync(string stackName)
    {
        EnsureHost();

        var (exitCode, stdout, _) = await _ssh.RunCommandAsync(
            _currentHost!, $"docker stack services {stackName} --format '{{{{.Name}}}}\\t{{{{.Image}}}}\\t{{{{.Replicas}}}}'");

        if (exitCode != 0 || string.IsNullOrWhiteSpace(stdout))
            return new List<ServiceInfo>();

        return stdout
            .Split('\n', StringSplitOptions.RemoveEmptyEntries)
            .Select(line =>
            {
                var parts = line.Split('\t', 3);
                return new ServiceInfo
                {
                    Name = parts.Length > 0 ? parts[0].Trim() : "",
                    Image = parts.Length > 1 ? parts[1].Trim() : "",
                    Replicas = parts.Length > 2 ? parts[2].Trim() : ""
                };
            })
            .ToList();
    }

    private void EnsureHost()
    {
        if (_currentHost == null)
            throw new InvalidOperationException("No SSH host configured. Call SetHost() before using Docker commands.");
    }
}