using System;
using System.Threading.Tasks;
using Bit.Core.Enums;
using Bit.Core.Models.Table;
using Bit.Core.Repositories;
using Bit.Core.Services;
using Bit.Portal.Models;
using Microsoft.AspNetCore.Authorization;
using Microsoft.AspNetCore.Mvc;

namespace Bit.Portal.Controllers
{
    [Authorize]
    public class PoliciesController : Controller
    {
        private readonly IUserService _userService;
        private readonly IOrganizationService _organizationService;
        private readonly IPolicyService _policyService;
        private readonly IPolicyRepository _policyRepository;
        private readonly EnterprisePortalCurrentContext _enterprisePortalCurrentContext;
        private readonly II18nService _i18nService;

        public PoliciesController(
            IUserService userService,
            IOrganizationService organizationService,
            IPolicyService policyService,
            IPolicyRepository policyRepository,
            EnterprisePortalCurrentContext enterprisePortalCurrentContext,
            II18nService i18nService)
        {
            _userService = userService;
            _organizationService = organizationService;
            _policyService = policyService;
            _policyRepository = policyRepository;
            _enterprisePortalCurrentContext = enterprisePortalCurrentContext;
            _i18nService = i18nService;
        }

        public async Task<IActionResult> Index()
        {
            var orgId = _enterprisePortalCurrentContext.SelectedOrganizationId;
            if (orgId == null)
            {
                return Redirect("~/");
            }

            if (!_enterprisePortalCurrentContext.SelectedOrganizationDetails.UsePolicies ||
                !_enterprisePortalCurrentContext.CanManagePoliciesForSelectedOrganization)
            {
                return Redirect("~/");
            }
            
            var policies = await _policyRepository.GetManyByOrganizationIdAsync(orgId.Value);
            var selectedOrgUseSso = _enterprisePortalCurrentContext.SelectedOrganizationDetails.UseSso;
            return View(new PoliciesModel(policies, selectedOrgUseSso));
        }
        
        [HttpGet("/edit/{type}")]
        public async Task<IActionResult> Edit(PolicyType type)
        {
            var orgId = _enterprisePortalCurrentContext.SelectedOrganizationId;
            if (orgId == null)
            {
                return Redirect("~");
            }

            if (!_enterprisePortalCurrentContext.SelectedOrganizationDetails.UsePolicies ||
                !_enterprisePortalCurrentContext.CanManagePoliciesForSelectedOrganization)
            {
                return Redirect("~/");
            }

            var policy = await _policyRepository.GetByOrganizationIdTypeAsync(orgId.Value, type);
            return BuildPolicyView(policy, type);
        }
        
        [HttpPost("/edit/{type}")]
        [ValidateAntiForgeryToken]
        public async Task<IActionResult> Edit(PolicyType type, PolicyEditModel model)
        {
            var orgId = _enterprisePortalCurrentContext.SelectedOrganizationId;
            if (orgId == null)
            {
                return Redirect("~");
            }

            if (!_enterprisePortalCurrentContext.SelectedOrganizationDetails.UsePolicies ||
                !_enterprisePortalCurrentContext.CanManagePoliciesForSelectedOrganization)
            {
                return Redirect("~/");
            }

            await ValidateDependentPolicies(type, orgId, model.Enabled);
            var policy = await _policyRepository.GetByOrganizationIdTypeAsync(orgId.Value, type);
            if (!ModelState.IsValid)
            {
                return BuildPolicyView(policy, type);
            }

            if (policy == null)
            {
                policy = model.ToPolicy(type, orgId.Value);
            }
            else
            {
                policy = model.ToPolicy(policy);
            }

            var userId = _userService.GetProperUserId(User);
            await _policyService.SaveAsync(policy, _userService, _organizationService, userId);
            return RedirectToAction("Edit", new { type });
        }

        private IActionResult BuildPolicyView(Policy policy, PolicyType type)
        {
            if (policy == null)
            {
                return View(new PolicyEditModel(type, _i18nService));
            }
            else
            {
                return View(new PolicyEditModel(policy, _i18nService));
            }
        }

        private async Task ValidateDependentPolicies(PolicyType type, Guid? orgId, bool enabled)
        {
            if (orgId == null)
            {
                throw new ArgumentNullException(nameof(orgId), "OrgId cannot be null");
            }
            
            switch(type)
            {
                case PolicyType.MasterPassword:
                case PolicyType.PasswordGenerator:
                case PolicyType.TwoFactorAuthentication:
                case PolicyType.PersonalOwnership:
                case PolicyType.DisableSend:
                case PolicyType.SendOptions:
                    break;
                
                case PolicyType.SingleOrg:
                    if (enabled)
                    {
                        break;
                    }

                    var requireSso =
                        await _policyRepository.GetByOrganizationIdTypeAsync(orgId.Value, PolicyType.RequireSso);
                    if (requireSso?.Enabled == true)
                    {
                        ModelState.AddModelError(string.Empty, _i18nService.T("DisableRequireSsoError"));
                    }
                    break;
                
                case PolicyType.RequireSso:
                    if (!enabled)
                    {
                        break;
                    }
                    
                    var singleOrg = await _policyRepository.GetByOrganizationIdTypeAsync(orgId.Value, PolicyType.SingleOrg);
                    if (singleOrg?.Enabled != true)
                    {
                        ModelState.AddModelError(string.Empty, _i18nService.T("RequireSsoPolicyReqError"));
                    }
                    break;
                
                default:
                    throw new ArgumentOutOfRangeException();
            }
        }
    }
}