src/main/java/de/uapcore/lightpit/modules/ProjectsModule.java

/*
 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.
 *
 * Copyright 2018 Mike Becker. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 *   1. Redistributions of source code must retain the above copyright
 *      notice, this list of conditions and the following disclaimer.
 *
 *   2. Redistributions in binary form must reproduce the above copyright
 *      notice, this list of conditions and the following disclaimer in the
 *      documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH DAMAGE.
 *
 */
package de.uapcore.lightpit.modules;


import de.uapcore.lightpit.*;
import de.uapcore.lightpit.dao.DataAccessObjects;
import de.uapcore.lightpit.entities.*;
import de.uapcore.lightpit.viewmodel.*;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.sql.Date;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.Objects;
import java.util.stream.Collectors;
import java.util.stream.Stream;

import static de.uapcore.lightpit.Functions.fqn;

@WebServlet(
        name = "ProjectsModule",
        urlPatterns = "/projects/*"
)
public final class ProjectsModule extends AbstractLightPITServlet {

    private static final Logger LOG = LoggerFactory.getLogger(ProjectsModule.class);

    public static final String SESSION_ATTR_SELECTED_PROJECT = fqn(ProjectsModule.class, "selected_project");
    public static final String SESSION_ATTR_SELECTED_ISSUE = fqn(ProjectsModule.class, "selected_issue");
    public static final String SESSION_ATTR_SELECTED_VERSION = fqn(ProjectsModule.class, "selected_version");

    private class SessionSelection {
        final HttpSession session;
        final HttpServletRequest req;
        final DataAccessObjects dao;
        Project project;
        Version version;
        Issue issue;

        SessionSelection(HttpServletRequest req, DataAccessObjects dao) {
            this.req = req;
            this.dao = dao;
            session = req.getSession();
        }

        void newProject() {
            project = null;
            version = null;
            issue = null;
            updateAttributes();
            project = new Project(-1);
            updateAttributes();
        }

        void newVersion() throws SQLException {
            project = (Project) session.getAttribute(SESSION_ATTR_SELECTED_PROJECT);
            syncProject();
            version = null;
            issue = null;
            updateAttributes();
            version = new Version(-1);
            version.setProject(project);
            updateAttributes();
        }

        void newIssue() throws SQLException {
            project = (Project) session.getAttribute(SESSION_ATTR_SELECTED_PROJECT);
            syncProject();
            version = null;
            issue = null;
            updateAttributes();
            issue = new Issue(-1);
            issue.setProject(project);
            updateAttributes();
        }

        void selectVersion(Version selectedVersion) throws SQLException {
            issue = null;
            version = selectedVersion;
            if (!version.getProject().equals(project)) {
                project = dao.getProjectDao().find(version.getProject().getId());
            }
            // our object contains more details
            version.setProject(project);
            updateAttributes();
        }

        void selectIssue(Issue selectedIssue) throws SQLException {
            issue = selectedIssue;
            if (!issue.getProject().equals(project)) {
                project = dao.getProjectDao().find(issue.getProject().getId());
            }
            // our object contains more details
            issue.setProject(project);
            if (!issue.getResolvedVersions().contains(version)
                    && !issue.getAffectedVersions().contains(version)) {
                version = null;
            }
            updateAttributes();
        }

        void syncProject() throws SQLException {
            final var projectSelection = getParameter(req, Integer.class, "pid");
            if (projectSelection.isPresent()) {
                final var selectedProject = dao.getProjectDao().find(projectSelection.get());
                if (!Objects.equals(selectedProject, project)) {
                    // reset version and issue if project changed
                    version = null;
                    issue = null;
                }
                project = selectedProject;
            } else {
                project = project == null ? null : dao.getProjectDao().find(project.getId());
            }
        }

        void syncVersion() throws SQLException {
            final var versionSelection = getParameter(req, Integer.class, "vid");
            if (versionSelection.isPresent()) {
                if (versionSelection.get() < 0) {
                    version = null;
                } else {
                    final var selectedVersion = dao.getVersionDao().find(versionSelection.get());
                    if (!Objects.equals(selectedVersion, version)) {
                        issue = null;
                    }
                    selectVersion(selectedVersion);
                }
            } else {
                version = version == null ? null : dao.getVersionDao().find(version.getId());
            }
        }

        void syncIssue() throws SQLException {
            final var issueSelection = getParameter(req, Integer.class, "issue");
            if (issueSelection.isPresent()) {
                final var selectedIssue = dao.getIssueDao().find(issueSelection.get());
                dao.getIssueDao().joinVersionInformation(selectedIssue);
                selectIssue(selectedIssue);
            } else {
                issue = issue == null ? null : dao.getIssueDao().find(issue.getId());
            }
        }

        void sync() throws SQLException {
            project = (Project) session.getAttribute(SESSION_ATTR_SELECTED_PROJECT);
            version = (Version) session.getAttribute(SESSION_ATTR_SELECTED_VERSION);
            issue = (Issue) session.getAttribute(SESSION_ATTR_SELECTED_ISSUE);

            syncProject();
            syncVersion();
            syncIssue();

            updateAttributes();
        }

        private void updateAttributes() {
            session.setAttribute(SESSION_ATTR_SELECTED_PROJECT, project);
            session.setAttribute(SESSION_ATTR_SELECTED_VERSION, version);
            session.setAttribute(SESSION_ATTR_SELECTED_ISSUE, issue);
        }
    }

    @Override
    protected String getResourceBundleName() {
        return "localization.projects";
    }


    private static final int BREADCRUMB_LEVEL_ROOT = 0;
    private static final int BREADCRUMB_LEVEL_PROJECT = 1;
    private static final int BREADCRUMB_LEVEL_VERSION = 2;
    private static final int BREADCRUMB_LEVEL_ISSUE_LIST = 3;
    private static final int BREADCRUMB_LEVEL_ISSUE = 4;

    /**
     * Creates the breadcrumb menu.
     *
     * @param level           the current active level (0: root, 1: project, 2: version, 3: issue list, 4: issue)
     * @param selection the currently selected objects
     * @return a dynamic breadcrumb menu trying to display as many levels as possible
     */
    private List<MenuEntry> getBreadcrumbs(int level, SessionSelection selection) {
        MenuEntry entry;

        final var breadcrumbs = new ArrayList<MenuEntry>();
        entry = new MenuEntry(new ResourceKey("localization.lightpit", "menu.projects"),
                "projects/");
        breadcrumbs.add(entry);
        if (level == BREADCRUMB_LEVEL_ROOT) entry.setActive(true);

        if (selection.project != null) {
            if (selection.project.getId() < 0) {
                entry = new MenuEntry(new ResourceKey("localization.projects", "button.create"),
                        "projects/edit");
            } else {
                entry = new MenuEntry(selection.project.getName(),
                        "projects/view?pid=" + selection.project.getId());
            }
            if (level == BREADCRUMB_LEVEL_PROJECT) entry.setActive(true);
            breadcrumbs.add(entry);
        }

        if (selection.version != null) {
            if (selection.version.getId() < 0) {
                entry = new MenuEntry(new ResourceKey("localization.projects", "button.version.create"),
                        "projects/versions/edit");
            } else {
                entry = new MenuEntry(selection.version.getName(),
                        "projects/versions/view?vid=" + selection.version.getId());
            }
            if (level == BREADCRUMB_LEVEL_VERSION) entry.setActive(true);
            breadcrumbs.add(entry);
        }

        if (selection.project != null) {
            String path = "projects/issues/?pid=" + selection.project.getId();
            if (selection.version != null) {
                path += "&vid="+selection.version.getId();
            }
            entry = new MenuEntry(new ResourceKey("localization.projects", "menu.issues"),
                    path);
            if (level == BREADCRUMB_LEVEL_ISSUE_LIST) entry.setActive(true);
            breadcrumbs.add(entry);
        }

        if (selection.issue != null) {
            if (selection.issue.getId() < 0) {
                entry = new MenuEntry(new ResourceKey("localization.projects", "button.issue.create"),
                        "projects/issues/edit");
            } else {
                entry = new MenuEntry("#" + selection.issue.getId(),
                        // TODO: maybe change link to a view rather than directly opening the editor
                        "projects/issues/edit?issue=" + selection.issue.getId());
            }
            if (level == BREADCRUMB_LEVEL_ISSUE) entry.setActive(true);
            breadcrumbs.add(entry);
        }

        return breadcrumbs;
    }

    @RequestMapping(method = HttpMethod.GET)
    public ResponseType index(HttpServletRequest req, DataAccessObjects dao) throws SQLException {
        final var sessionSelection = new SessionSelection(req, dao);
        sessionSelection.sync();

        final var projectDao = dao.getProjectDao();
        final var versionDao = dao.getVersionDao();

        final var projectList = projectDao.list();

        final var viewModel = new ProjectIndexView();
        for (var project : projectList) {
            final var info = new ProjectInfo(project);
            info.setVersions(versionDao.list(project));
            info.setIssueSummary(projectDao.getIssueSummary(project));
            viewModel.getProjects().add(info);
        }

        setViewModel(req, viewModel);
        setContentPage(req, "projects");
        setStylesheet(req, "projects");

        setBreadcrumbs(req, getBreadcrumbs(BREADCRUMB_LEVEL_ROOT, sessionSelection));

        return ResponseType.HTML;
    }

    private ProjectEditView configureEditForm(HttpServletRequest req, DataAccessObjects dao, SessionSelection selection) throws SQLException {
        final var viewModel = new ProjectEditView();
        viewModel.setProject(selection.project);
        viewModel.setUsers(dao.getUserDao().list());
        setViewModel(req, viewModel);
        setContentPage(req, "project-form");
        setBreadcrumbs(req, getBreadcrumbs(BREADCRUMB_LEVEL_PROJECT, selection));
        return viewModel;
    }

    @RequestMapping(requestPath = "edit", method = HttpMethod.GET)
    public ResponseType edit(HttpServletRequest req, DataAccessObjects dao) throws SQLException {
        final var selection = new SessionSelection(req, dao);
        if (getParameter(req, Integer.class, "pid").isEmpty()) {
            selection.newProject();
        } else {
            selection.sync();
        }

        configureEditForm(req, dao, selection);

        return ResponseType.HTML;
    }

    @RequestMapping(requestPath = "commit", method = HttpMethod.POST)
    public ResponseType commit(HttpServletRequest req, DataAccessObjects dao) throws SQLException {

        Project project = new Project(-1);
        try {
            project = new Project(getParameter(req, Integer.class, "id").orElseThrow());
            project.setName(getParameter(req, String.class, "name").orElseThrow());
            getParameter(req, String.class, "description").ifPresent(project::setDescription);
            getParameter(req, String.class, "repoUrl").ifPresent(project::setRepoUrl);
            getParameter(req, Integer.class, "owner").map(
                    ownerId -> ownerId >= 0 ? new User(ownerId) : null
            ).ifPresent(project::setOwner);

            dao.getProjectDao().saveOrUpdate(project);

            setRedirectLocation(req, "./projects/");
            setContentPage(req, Constants.JSP_COMMIT_SUCCESSFUL);
            LOG.debug("Successfully updated project {}", project.getName());
        } catch (NoSuchElementException | IllegalArgumentException | SQLException ex) {
            LOG.warn("Form validation failure: {}", ex.getMessage());
            LOG.debug("Details:", ex);
            final var selection = new SessionSelection(req, dao);
            selection.project = project;
            final var vm = configureEditForm(req, dao, selection);
            vm.setErrorText(ex.getMessage()); // TODO: error text
        }

        return ResponseType.HTML;
    }

    @RequestMapping(requestPath = "view", method = HttpMethod.GET)
    public ResponseType view(HttpServletRequest req, HttpServletResponse resp, DataAccessObjects dao) throws SQLException, IOException {
        final var selection = new SessionSelection(req, dao);
        selection.sync();

        if (selection.project == null) {
            resp.sendError(HttpServletResponse.SC_NOT_FOUND, "No project selected.");
            return ResponseType.NONE;
        }

        final var versionDao = dao.getVersionDao();
        final var issueDao = dao.getIssueDao();

        final var viewModel = new ProjectView(selection.project);
        final var issues = issueDao.list(selection.project);
        for (var issue : issues) issueDao.joinVersionInformation(issue);
        viewModel.setIssues(issues);
        viewModel.setVersions(versionDao.list(selection.project));
        viewModel.updateVersionInfo();
        setViewModel(req, viewModel);

        setBreadcrumbs(req, getBreadcrumbs(BREADCRUMB_LEVEL_PROJECT, selection));
        setContentPage(req, "project-details");
        setStylesheet(req, "projects");

        return ResponseType.HTML;
    }

    @RequestMapping(requestPath = "versions/view", method = HttpMethod.GET)
    public ResponseType viewVersion(HttpServletRequest req, HttpServletResponse resp, DataAccessObjects dao) throws SQLException, IOException {
        final var selection = new SessionSelection(req, dao);
        selection.sync();
        if (selection.version == null) {
            resp.sendError(HttpServletResponse.SC_NOT_FOUND);
            return ResponseType.NONE;
        }

        final var issueDao = dao.getIssueDao();
        final var viewModel = new VersionView(selection.version);
        final var issues = issueDao.list(selection.version);
        for (var issue : issues) issueDao.joinVersionInformation(issue);
        viewModel.setIssues(issues);
        setViewModel(req, viewModel);

        setBreadcrumbs(req, getBreadcrumbs(BREADCRUMB_LEVEL_VERSION, selection));
        setContentPage(req, "version");
        setStylesheet(req, "projects");

        return ResponseType.HTML;
    }

    private VersionEditView configureEditVersionForm(HttpServletRequest req, DataAccessObjects dao, SessionSelection selection) throws SQLException {
        final var viewModel = new VersionEditView(selection.version);
        if (selection.version.getProject() == null) {
            viewModel.setProjects(dao.getProjectDao().list());
        }
        setViewModel(req, viewModel);
        setContentPage(req, "version-form");
        setBreadcrumbs(req, getBreadcrumbs(BREADCRUMB_LEVEL_VERSION, selection));
        return viewModel;
    }

    @RequestMapping(requestPath = "versions/edit", method = HttpMethod.GET)
    public ResponseType editVersion(HttpServletRequest req, DataAccessObjects dao) throws SQLException {
        final var selection = new SessionSelection(req, dao);
        if (getParameter(req, Integer.class, "vid").isEmpty()) {
            selection.newVersion();
        } else {
            selection.sync();
        }

        configureEditVersionForm(req, dao, selection);

        return ResponseType.HTML;
    }

    @RequestMapping(requestPath = "versions/commit", method = HttpMethod.POST)
    public ResponseType commitVersion(HttpServletRequest req, HttpServletResponse resp, DataAccessObjects dao) throws SQLException {

        var version = new Version(-1);
        try {
            version = new Version(getParameter(req, Integer.class, "id").orElseThrow());
            version.setProject(new Project(getParameter(req, Integer.class, "pid").orElseThrow()));
            version.setName(getParameter(req, String.class, "name").orElseThrow());
            getParameter(req, Integer.class, "ordinal").ifPresent(version::setOrdinal);
            version.setStatus(VersionStatus.valueOf(getParameter(req, String.class, "status").orElseThrow()));
            dao.getVersionDao().saveOrUpdate(version);

            // specifying the pid parameter will purposely reset the session selected version!
            setRedirectLocation(req, "./projects/view?pid="+version.getProject().getId());
            setContentPage(req, Constants.JSP_COMMIT_SUCCESSFUL);
        } catch (NoSuchElementException | IllegalArgumentException | SQLException ex) {
            LOG.warn("Form validation failure: {}", ex.getMessage());
            LOG.debug("Details:", ex);
            final var selection = new SessionSelection(req, dao);
            selection.selectVersion(version);
            final var viewModel = configureEditVersionForm(req, dao, selection);
            // TODO: set Error Text
        }

        return ResponseType.HTML;
    }

    private IssueEditView configureEditIssueForm(HttpServletRequest req, DataAccessObjects dao, SessionSelection selection) throws SQLException {
        final var viewModel = new IssueEditView(selection.issue);

        if (selection.issue.getProject() == null) {
            viewModel.setProjects(dao.getProjectDao().list());
        } else {
            viewModel.setVersions(dao.getVersionDao().list(selection.issue.getProject()));
        }
        viewModel.setUsers(dao.getUserDao().list());
        setViewModel(req, viewModel);

        setContentPage(req, "issue-form");
        setBreadcrumbs(req, getBreadcrumbs(BREADCRUMB_LEVEL_ISSUE, selection));
        return viewModel;
    }

    @RequestMapping(requestPath = "issues/", method = HttpMethod.GET)
    public ResponseType issues(HttpServletRequest req, HttpServletResponse resp, DataAccessObjects dao) throws SQLException, IOException {
        final var selection = new SessionSelection(req, dao);
        selection.sync();
        if (selection.project == null) {
            resp.sendError(HttpServletResponse.SC_NOT_FOUND, "No project selected.");
            return ResponseType.NONE;
        }

        final var viewModel = new IssuesView();
        viewModel.setProject(selection.project);
        if (selection.version == null) {
            viewModel.setIssues(dao.getIssueDao().list(selection.project));
        } else {
            viewModel.setVersion(selection.version);
            viewModel.setIssues(dao.getIssueDao().list(selection.version));
        }
        setViewModel(req, viewModel);

        setBreadcrumbs(req, getBreadcrumbs(BREADCRUMB_LEVEL_ISSUE_LIST, selection));
        setContentPage(req, "issues");
        setStylesheet(req, "projects");

        return ResponseType.HTML;
    }

    @RequestMapping(requestPath = "issues/edit", method = HttpMethod.GET)
    public ResponseType editIssue(HttpServletRequest req, HttpServletResponse resp, DataAccessObjects dao) throws SQLException {
        final var selection = new SessionSelection(req, dao);
        if (getParameter(req, Integer.class, "issue").isEmpty()) {
            selection.newIssue();
        } else {
            selection.sync();
        }

        configureEditIssueForm(req, dao, selection);

        return ResponseType.HTML;
    }

    @RequestMapping(requestPath = "issues/commit", method = HttpMethod.POST)
    public ResponseType commitIssue(HttpServletRequest req, HttpServletResponse resp, DataAccessObjects dao) throws SQLException {

        Issue issue = new Issue(-1);
        try {
            issue = new Issue(getParameter(req, Integer.class, "id").orElseThrow());
            issue.setProject(new Project(getParameter(req, Integer.class, "pid").orElseThrow()));
            getParameter(req, String.class, "category").map(IssueCategory::valueOf).ifPresent(issue::setCategory);
            getParameter(req, String.class, "status").map(IssueStatus::valueOf).ifPresent(issue::setStatus);
            issue.setSubject(getParameter(req, String.class, "subject").orElseThrow());
            getParameter(req, Integer.class, "assignee").map(
                    userid -> userid >= 0 ? new User(userid) : null
            ).ifPresent(issue::setAssignee);
            getParameter(req, String.class, "description").ifPresent(issue::setDescription);
            getParameter(req, Date.class, "eta").ifPresent(issue::setEta);

            getParameter(req, Integer[].class, "affected")
                    .map(Stream::of)
                    .map(stream ->
                        stream.map(Version::new).collect(Collectors.toList())
                    ).ifPresent(issue::setAffectedVersions);
            getParameter(req, Integer[].class, "resolved")
                    .map(Stream::of)
                    .map(stream ->
                            stream.map(Version::new).collect(Collectors.toList())
                    ).ifPresent(issue::setResolvedVersions);

            dao.getIssueDao().saveOrUpdate(issue);

            // specifying the issue parameter keeps the edited issue as breadcrumb
            setRedirectLocation(req, "./projects/issues/?issue="+issue.getId());
            setContentPage(req, Constants.JSP_COMMIT_SUCCESSFUL);
        } catch (NoSuchElementException | IllegalArgumentException | SQLException ex) {
            // TODO: set request attribute with error text
            LOG.warn("Form validation failure: {}", ex.getMessage());
            LOG.debug("Details:", ex);
            final var selection = new SessionSelection(req, dao);
            selection.selectIssue(issue);
            final var viewModel = configureEditIssueForm(req, dao, selection);
            // TODO: set Error Text
        }

        return ResponseType.HTML;
    }
}