using System.Text.Json;
using HrynCo.NotificationService.DAL.Abstract.Templates;
using HrynCo.NotificationService.Services.EmailTemplates.Create;
using HrynCo.NotificationService.Services.EmailTemplates.Delete;
using HrynCo.NotificationService.Services.EmailTemplates.Get;
using HrynCo.NotificationService.Services.EmailTemplates.GetAll;
using HrynCo.NotificationService.Services.EmailTemplates.Update;
using HrynCo.NotificationService.Web.Controllers.Admin.ViewModels;
using MediatR;
using Microsoft.AspNetCore.Mvc;

namespace HrynCo.NotificationService.Web.Controllers.Admin;

[Route("admin/templates")]
public class AdminTemplatesController : Controller
{
    private readonly IMediator _mediator;

    public AdminTemplatesController(IMediator mediator)
    {
        _mediator = mediator;
    }

    // GET /admin/templates
    [HttpGet("")]
    public async Task<IActionResult> Index(CancellationToken ct)
    {
        var result = await _mediator.Send(new GetAllEmailTemplatesQuery(), ct);
        if (!result.IsSuccess)
        {
            ModelState.AddModelError("", result.Error?.Message ?? "Failed to load templates.");
            return View(Array.Empty<EmailTemplate>());
        }

        return View(result.Result);
    }

    // GET /admin/templates/create
    [HttpGet("create")]
    public IActionResult Create()
    {
        return View("Edit", new EmailTemplateEditViewModel());
    }

    // GET /admin/templates/{serviceName}/{key}/{languageCode}
    [HttpGet("{serviceName}/{key}/{languageCode}")]
    public async Task<IActionResult> Edit(string serviceName, string key, string languageCode, CancellationToken ct)
    {
        var result = await _mediator.Send(new GetEmailTemplateQuery(serviceName, key, languageCode), ct);
        if (!result.IsSuccess || result.Result is null)
            return NotFound();

        var template = result.Result;
        var vm = new EmailTemplateEditViewModel
        {
            Id = template.Id,
            ServiceName = template.ServiceName,
            Key = template.Key,
            LanguageCode = template.LanguageCode,
            Subject = template.Subject,
            HtmlBody = template.HtmlBody,
            TextBody = template.TextBody,
            VariablesJson = JsonSerializer.Serialize(template.Variables)
        };

        return View(vm);
    }

    // POST /admin/templates/save
    [HttpPost("save")]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Save(EmailTemplateEditViewModel model, CancellationToken ct)
    {
        if (!ModelState.IsValid)
            return View("Edit", model);

        List<EmailTemplateVariable> variables;
        try
        {
            variables = JsonSerializer.Deserialize<List<EmailTemplateVariable>>(model.VariablesJson,
                new JsonSerializerOptions { PropertyNameCaseInsensitive = true })
                ?? [];
        }
        catch (JsonException)
        {
            ModelState.AddModelError(nameof(model.VariablesJson), "Invalid JSON format for variables.");
            return View("Edit", model);
        }

        if (model.IsNew)
        {
            var command = new CreateEmailTemplateCommand(
                model.ServiceName,
                model.Key,
                model.LanguageCode,
                model.Subject,
                model.HtmlBody,
                model.TextBody,
                variables);

            var result = await _mediator.Send(command, ct);
            if (!result.IsSuccess)
            {
                ModelState.AddModelError("", result.Error?.Message ?? "Failed to create template.");
                return View("Edit", model);
            }
        }
        else
        {
            var command = new UpdateEmailTemplateCommand(
                model.ServiceName,
                model.Key,
                model.LanguageCode,
                model.Subject,
                model.HtmlBody,
                model.TextBody,
                variables);

            var result = await _mediator.Send(command, ct);
            if (!result.IsSuccess)
            {
                ModelState.AddModelError("", result.Error?.Message ?? "Failed to update template.");
                return View("Edit", model);
            }
        }

        return RedirectToAction(nameof(Index));
    }

    // POST /admin/templates/{serviceName}/{key}/{languageCode}/delete
    [HttpPost("{serviceName}/{key}/{languageCode}/delete")]
    [ValidateAntiForgeryToken]
    public async Task<IActionResult> Delete(string serviceName, string key, string languageCode, CancellationToken ct)
    {
        await _mediator.Send(new DeleteEmailTemplateCommand(serviceName, key, languageCode), ct);
        return RedirectToAction(nameof(Index));
    }
}