package uk.ac.ox.zoo.seeg.abraid.mp.publicsite.web.user;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.ModelMap;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;
import uk.ac.ox.zoo.seeg.abraid.mp.common.service.core.ExpertService;

/**
 * Controller for displaying list of publicly visible experts.
 * Copyright (c) 2014 University of Oxford
 */
@Controller
public class ContributorsController {
    private static final int PAGE_SIZE = 16;
    private ExpertService expertService;

    @Autowired
    public ContributorsController(ExpertService expertService) {
        this.expertService = expertService;
    }

    /**
     * Shows the experts page.
     * @param model The templating model.
     * @param page The page number to display.
     * @return The ftl page name.
     */
    @RequestMapping(value = "/experts", method = RequestMethod.GET)
    public String showExperts(ModelMap model, Integer page) {
        final int pageCount = calculatePageCount(expertService.getCountOfPubliclyVisibleExperts());

        if (page != null && page >= 1 && page <= pageCount) {
            model.addAttribute("page", expertService.getPageOfPubliclyVisibleExperts(page, PAGE_SIZE));
            model.addAttribute("pageCount", pageCount);
            model.addAttribute("pageNumber", page);
            return "experts";
        } else {
            return "redirect:/experts?page=1";
        }
    }

    private static int calculatePageCount(final long expertCount) {
        final long pageCount = (expertCount + PAGE_SIZE - 1) / PAGE_SIZE;
        return (int) Math.max(pageCount, 1);
    }
}