ApiController vs Controller

CampaignsApiController.cs

using System.Linq;
using System.Web.Http;
using DirectAgents.Domain.Concrete;
using EomToolWeb.Models;

namespace EomToolWeb.Controllers
{
    public class CampaignsApiController : ApiController
    {
        private EFDbContext db = new EFDbContext();

        public IQueryable<CampaignViewModel> Get()
        {
            var query = db.Campaigns
                          .AsEnumerable()
                          .Select(c => new CampaignViewModel(c));

            return query.AsQueryable();
        }

        public IQueryable<CampaignViewModel> Get(string vertical, string traffictype, string search, string country, int? pid)
        {
            var campaigns = db.Campaigns.AsQueryable();

            if (!string.IsNullOrWhiteSpace(vertical))
            {
                var cr = db.Verticals.Where(v => v.Name == vertical).FirstOrDefault();
                if (cr != null)
                    campaigns = campaigns.Where(c => c.Vertical.Name == vertical);
            }

            if (!string.IsNullOrWhiteSpace(traffictype))
            {
                var tt = db.TrafficTypes.Where(t => t.Name == traffictype).FirstOrDefault();
                if (tt != null)
                    campaigns = campaigns.Where(c => c.TrafficTypes.Select(t => t.Name).Contains(traffictype));
            }

            if (!string.IsNullOrWhiteSpace(search))
            {
                campaigns = campaigns.Where(c => c.Name.Contains(search) || c.Description.Contains(search));
            }

            if (!string.IsNullOrWhiteSpace(country))
            {
                campaigns = campaigns.Where(camp => camp.Countries.Select(c => c.CountryCode).Contains(country));
            }

            if (pid != null)
            {
                campaigns = campaigns.Where(c => c.Pid == pid.Value);
            }

            var query = campaigns
                       .AsEnumerable()
                       .Select(c => new CampaignViewModel(c))
                       .AsQueryable();

            return query;
        }

        protected override void Dispose(bool disposing)
        {
            db.Dispose();
            base.Dispose(disposing);
        }
    }
}

CampaignsController.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web.Mvc;
using DirectAgents.Domain.Abstract;
using DirectAgents.Domain.DTO;
using DirectAgents.Domain.Entities;
using EomToolWeb.Models;

namespace EomToolWeb.Controllers
{
    public class CampaignsController : Controller
    {
        private ICampaignRepository campaignRepository;

        public CampaignsController(ICampaignRepository campaignRepository)
        {
            this.campaignRepository = campaignRepository;
        }

        public ActionResult List(string searchstring, string pid, string country, string vertical, string traffictype)
        {
            var viewModel = new CampaignsListViewModel();
            var campaigns = campaignRepository.Campaigns;

            if (!string.IsNullOrWhiteSpace(searchstring))
            {
                viewModel.SearchString = searchstring;
                campaigns = campaigns.Where(c => c.Name.Contains(searchstring));
            }
            int pidInt;
            if (Int32.TryParse(pid, out pidInt))
            {
                viewModel.Pid = pidInt;
                campaigns = campaigns.Where(c => c.Pid == pidInt);
            }
            if (!string.IsNullOrWhiteSpace(country))
            {
                viewModel.Country = campaignRepository.Countries.Where(c => c.CountryCode == country).FirstOrDefault();
                if (viewModel.Country != null)
                    campaigns = campaigns.Where(camp => camp.Countries.Select(c => c.CountryCode).Contains(country));
            }
            if (!string.IsNullOrWhiteSpace(vertical))
            {
                viewModel.Vertical = campaignRepository.Verticals.Where(v => v.Name == vertical).FirstOrDefault();
                if (viewModel.Vertical != null)
                    campaigns = campaigns.Where(c => c.Vertical.Name == vertical);
            }
            if (!string.IsNullOrWhiteSpace(traffictype))
            {
                viewModel.TrafficType = campaignRepository.TrafficTypes.Where(t => t.Name == traffictype).FirstOrDefault();
                if (viewModel.TrafficType != null)
                    campaigns = campaigns.Where(c => c.TrafficTypes.Select(t => t.Name).Contains(traffictype));
            }

            viewModel.Campaigns = campaigns.AsEnumerable();
            return View(viewModel);
        }

        public ActionResult List2(string search, string pid, string country, string vertical, string traffictype)
        {
            var viewModel = new CampaignsListViewModel();
            if (!string.IsNullOrWhiteSpace(search))
            {
                viewModel.SearchString = search;
            }
            int pidInt;
            if (Int32.TryParse(pid, out pidInt))
            {
                viewModel.Pid = pidInt;
            }
            if (!string.IsNullOrWhiteSpace(country))
            {
                viewModel.Country = campaignRepository.Countries.Where(c => c.CountryCode == country).FirstOrDefault();
            }
            if (!string.IsNullOrWhiteSpace(vertical))
            {
                viewModel.Vertical = campaignRepository.Verticals.Where(v => v.Name == vertical).FirstOrDefault();
            }
            if (!string.IsNullOrWhiteSpace(traffictype))
            {
                viewModel.TrafficType = campaignRepository.TrafficTypes.Where(t => t.Name == traffictype).FirstOrDefault();
            }
            return View(viewModel);
        }

        public ActionResult ListByCountry()
        {
            var countryCodes = campaignRepository.AllCountryCodes;
            ViewBag.CountryCodes = countryCodes.ToList();
            var countries = campaignRepository.Countries.OrderByDescending(c => c.Campaigns.Count());
            return View(countries);
        }

        public ActionResult Search()
        {
            var countryCodes = campaignRepository.AllCountryCodes;
            return View(countryCodes);
        }

        public ActionResult ShowCountries()
        {
            var countryCodes = campaignRepository.AllCountryCodes;
            return View(countryCodes);
        }

        public ActionResult Show(int pid)
        {
            var campaign = campaignRepository.Campaigns.Where(c => c.Pid == pid).FirstOrDefault();
            if (campaign == null)
            {
                return Content("campaign not found");
            }
            return PartialView(new CampaignViewModel(campaign));
        }

        [HttpGet]
        public ActionResult Edit(int pid)
        {
            var campaign = campaignRepository.Campaigns.Where(c => c.Pid == pid).FirstOrDefault();
            if (campaign == null)
            {
                return Content("campaign not found");
            }
            return PartialView(campaign);
        }

        [HttpPost]
        public ActionResult Edit(Campaign campaign)
        {
            if (ModelState.IsValid)
            {
                var existingCampaign = campaignRepository.FindById(campaign.Pid);
                if (existingCampaign != null)
                {
                    TryUpdateModel(existingCampaign);
                    campaignRepository.SaveChanges();
                }
                // else... set a ModelState error?
            }

            if (Request.IsAjaxRequest())
                return Json(new { IsValid = ModelState.IsValid });
            else
                return View(campaign);
        }

        [HttpPost]
        public ActionResult Edit2(Campaign campaign)
        {
            var c = campaignRepository.FindById(campaign.Pid);
            if (c != null)
            {
                c.Name = campaign.Name;
                c.Description = campaign.Description;
                c.PayableAction = campaign.PayableAction;
                c.Link = campaign.Link;
                c.Cost = campaign.Cost;
                c.Revenue = campaign.Revenue;
                c.ImportantDetails = campaign.ImportantDetails;
                c.BannedNetworks = campaign.BannedNetworks;
                c.CampaignCap = campaign.CampaignCap;
                c.ScrubPolicy = campaign.ScrubPolicy;
                c.EomNotes = campaign.EomNotes;
                campaignRepository.SaveChanges();
            }

            return null;
        }

        public ActionResult Top(TopCampaignsBy by, string traffictype)
        {
            TrafficType trafficTypeEntity = null;

            if (traffictype != null)
                trafficTypeEntity = campaignRepository.TrafficTypes.SingleOrDefault(t => t.Name == traffictype);

            IEnumerable<CampaignSummary> campaignSummaries;

            if (trafficTypeEntity == null) // no matching traffic type
                campaignSummaries = campaignRepository.TopCampaigns(20, by, null);
            else
                campaignSummaries = campaignRepository.TopCampaigns(20, by, traffictype);

            var model = new TopViewModel { CampaignSummaries = campaignSummaries, By = by, TrafficType = trafficTypeEntity };

            return View(model);
        }
    }
}