using FluentValidation;
using Microsoft.AspNetCore.Mvc;
using Microsoft.EntityFrameworkCore;
using Meezi.API.Models.Cafes;
using Meezi.API.Services;
using Meezi.Core.Authorization;
using Meezi.Core.Enums;
using Meezi.Core.Interfaces;
using Meezi.Core.Utilities;
using Meezi.Infrastructure.Branding;
using Meezi.Infrastructure.Data;
using Meezi.Infrastructure.Services.Platform;
using Meezi.Shared;

namespace Meezi.API.Controllers;

[Route("api/cafes/{cafeId}/settings")]
public class CafeSettingsController : CafeApiControllerBase
{
    private readonly AppDbContext _db;
    private readonly IValidator<PatchCafeSettingsRequest> _validator;
    private readonly IPlatformCatalogService _catalog;

    public CafeSettingsController(
        AppDbContext db,
        IValidator<PatchCafeSettingsRequest> validator,
        IPlatformCatalogService catalog)
    {
        _db = db;
        _validator = validator;
        _catalog = catalog;
    }

    [HttpGet]
    public async Task<IActionResult> Get(string cafeId, ITenantContext tenant, CancellationToken ct)
    {
        if (EnsureCafeAccess(cafeId, tenant) is { } denied) return denied;
        var cafe = await _db.Cafes.AsNoTracking().FirstOrDefaultAsync(c => c.Id == cafeId, ct);
        if (cafe is null) return NotFoundError();
        return Ok(new ApiResponse<CafeSettingsDto>(true, ToDto(cafe)));
    }

    [HttpPatch]
    public async Task<IActionResult> Patch(
        string cafeId,
        [FromBody] PatchCafeSettingsRequest request,
        ITenantContext tenant,
        CancellationToken ct)
    {
        if (EnsureCafeAccess(cafeId, tenant) is { } denied) return denied;
        if (EnsurePermission(tenant, Permission.ManageCafeSettings) is { } permDenied) return permDenied;

        var validation = await _validator.ValidateAsync(request, ct);
        if (!validation.IsValid)
        {
            var first = validation.Errors.First();
            return BadRequest(new ApiResponse<object>(false, null,
                new ApiError("VALIDATION_ERROR", first.ErrorMessage, first.PropertyName)));
        }

        if (request.DefaultTaxRate is not null || request.AllowBranchTaxOverride is not null)
        {
            if (EnsureOwner(tenant) is { } ownerDenied) return ownerDenied;
        }

        var cafe = await _db.Cafes.FirstOrDefaultAsync(c => c.Id == cafeId, ct);
        if (cafe is null) return NotFoundError();

        if (request.Name is not null) cafe.Name = request.Name.Trim();

        if (request.Slug is not null)
        {
            var newSlug = request.Slug.Trim().ToLowerInvariant();
            if (!SlugHelper.IsValidSlug(newSlug))
                return BadRequest(new ApiResponse<object>(false, null,
                    new ApiError("INVALID_SLUG", "Slug must be 2-80 lowercase letters, digits, or hyphens.")));

            var taken = await _db.Cafes.AnyAsync(c => c.Slug == newSlug && c.Id != cafeId, ct);
            if (taken)
                return Conflict(new ApiResponse<object>(false, null,
                    new ApiError("SLUG_TAKEN", "This Koja profile address is already in use. Please choose another.")));

            cafe.Slug = newSlug;
        }
        if (request.Phone is not null) cafe.Phone = request.Phone.Trim();
        if (request.Address is not null) cafe.Address = request.Address.Trim();
        if (request.City is not null) cafe.City = request.City.Trim();
        if (request.Description is not null) cafe.Description = request.Description.Trim();
        if (request.LogoUrl is not null) cafe.LogoUrl = request.LogoUrl.Trim();
        if (request.CoverImageUrl is not null) cafe.CoverImageUrl = request.CoverImageUrl.Trim();
        if (request.SnappfoodVendorId is not null) cafe.SnappfoodVendorId = request.SnappfoodVendorId.Trim();
        if (request.Theme is not null)
        {
            // Custom menu styling is a paid feature (Starter+). Only block an actual change,
            // so a normal settings save that re-sends the current theme isn't rejected.
            var newThemeJson = CafeThemeSerializer.Serialize(CafeThemeMapping.FromDto(request.Theme));
            if (newThemeJson != cafe.ThemeJson)
            {
                var styleTier = tenant.PlanTier ?? PlanTier.Free;
                if (!await _catalog.IsFeatureEnabledForCafeAsync(cafeId, styleTier, "custom_menu_styling", ct))
                    return StatusCode(403, new ApiResponse<object>(false, null,
                        new ApiError("PLAN_FEATURE_DISABLED", "Custom menu styling is not included in your plan. Please upgrade.")));
                cafe.ThemeJson = newThemeJson;
            }
        }
        if (request.DefaultTaxRate is decimal taxRate)
            cafe.DefaultTaxRate = taxRate;
        if (request.AllowBranchTaxOverride is bool allowTax)
            cafe.AllowBranchTaxOverride = allowTax;

        // Location: explicit null-clear flag OR new values
        if (request.ClearLocation)
        {
            cafe.Latitude = null;
            cafe.Longitude = null;
        }
        else if (request.Latitude.HasValue && request.Longitude.HasValue)
        {
            if (request.Latitude is < -90 or > 90 || request.Longitude is < -180 or > 180)
                return BadRequest(new ApiResponse<object>(false, null,
                    new ApiError("INVALID_LOCATION", "Latitude must be −90…90 and longitude −180…180.")));
            cafe.Latitude = request.Latitude;
            cafe.Longitude = request.Longitude;
        }

        await _db.SaveChangesAsync(ct);
        return Ok(new ApiResponse<CafeSettingsDto>(true, ToDto(cafe)));
    }

    private static CafeSettingsDto ToDto(Core.Entities.Cafe cafe) => new(
        cafe.Id,
        cafe.Name,
        cafe.Slug,
        cafe.Phone,
        cafe.Address,
        cafe.City,
        cafe.Description,
        cafe.LogoUrl,
        cafe.CoverImageUrl,
        cafe.SnappfoodVendorId,
        cafe.PlanTier.ToString(),
        cafe.PlanExpiresAt,
        CafeThemeMapping.FromJson(cafe.ThemeJson),
        cafe.DefaultTaxRate,
        cafe.AllowBranchTaxOverride,
        cafe.Latitude,
        cafe.Longitude);
}