cacert-boardvoting/cmd/boardvoting/handlers.go

/*
Copyright 2017-2022 CAcert Inc.
SPDX-License-Identifier: Apache-2.0

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

    http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/

package main

import (
	"bytes"
	"database/sql"
	"errors"
	"fmt"
	"html/template"
	"io/fs"
	"net/http"
	"path/filepath"
	"strings"
	"time"

	"github.com/Masterminds/sprig/v3"
	"github.com/gorilla/csrf"
	"github.com/julienschmidt/httprouter"

	"git.cacert.org/cacert-boardvoting/internal/models"
	"git.cacert.org/cacert-boardvoting/internal/validator"
	"git.cacert.org/cacert-boardvoting/ui"
)

func checkRole(v *models.User, roles []string) (bool, error) {
	hasRole, err := v.HasRole(roles)
	if err != nil {
		return false, fmt.Errorf("could not determine user roles: %w", err)
	}

	return hasRole, nil
}

func newTemplateCache() (map[string]*template.Template, error) {
	cache := map[string]*template.Template{}

	pages, err := fs.Glob(ui.Files, "html/pages/*.html")
	if err != nil {
		return nil, fmt.Errorf("could not find page templates: %w", err)
	}

	funcMaps := sprig.FuncMap()
	funcMaps["nl2br"] = func(text string) template.HTML {
		// #nosec G203 input is sanitized
		return template.HTML(strings.ReplaceAll(template.HTMLEscapeString(text), "\n", "<br>"))
	}
	funcMaps["canManageUsers"] = func(v *models.User) (bool, error) {
		return checkRole(v, []string{models.RoleSecretary, models.RoleAdmin})
	}
	funcMaps["canVote"] = func(v *models.User) (bool, error) {
		return checkRole(v, []string{models.RoleVoter})
	}
	funcMaps["canStartVote"] = func(v *models.User) (bool, error) {
		return checkRole(v, []string{models.RoleVoter})
	}
	funcMaps[csrf.TemplateTag] = csrf.TemplateField

	for _, page := range pages {
		name := filepath.Base(page)

		ts, err := template.New("").Funcs(funcMaps).ParseFS(
			ui.Files,
			"html/base.html",
			"html/partials/*.html",
			page,
		)
		if err != nil {
			return nil, fmt.Errorf("could not parse base template: %w", err)
		}

		cache[name] = ts
	}

	return cache, nil
}

type topLevelNavItem string
type subLevelNavItem string

const (
	topLevelNavMotions topLevelNavItem = "motions"
	topLevelNavUsers   topLevelNavItem = "users"

	subLevelNavMotionsAll     subLevelNavItem = "all-motions"
	subLevelNavMotionsUnvoted subLevelNavItem = "unvoted-motions"
	subLevelNavUsers          subLevelNavItem = "users"
)

type templateData struct {
	PrevPage     string
	NextPage     string
	Motion       *models.MotionForDisplay
	Motions      []*models.MotionForDisplay
	User         *models.User
	Users        []*models.User
	Request      *http.Request
	Flash        string
	Form         any
	ActiveNav    topLevelNavItem
	ActiveSubNav subLevelNavItem
}

func (app *application) newTemplateData(
	r *http.Request,
	nav topLevelNavItem,
	subNav subLevelNavItem,
) *templateData {
	user, err := app.GetUser(r)
	if err != nil {
		app.errorLog.Printf("error getting user for template data: %v", err)
	}

	return &templateData{
		Request:      r,
		User:         user,
		ActiveNav:    nav,
		ActiveSubNav: subNav,
		Flash:        app.sessionManager.PopString(r.Context(), "flash"),
	}
}

func (app *application) render(w http.ResponseWriter, status int, page string, data *templateData) {
	ts, ok := app.templateCache[page]
	if !ok {
		app.serverError(w, fmt.Errorf("the template %s does not exist", page))

		return
	}

	buf := new(bytes.Buffer)

	err := ts.ExecuteTemplate(buf, "base", data)
	if err != nil {
		app.serverError(w, err)

		return
	}

	w.WriteHeader(status)

	_, _ = buf.WriteTo(w)
}

func (m *templateData) motionPaginationOptions(limit int, first, last *time.Time) error {
	motions := m.Motions

	if len(motions) == limit && first.Before(motions[len(motions)-1].Proposed) {
		marshalled, err := motions[len(motions)-1].Proposed.MarshalText()
		if err != nil {
			return fmt.Errorf("could not serialize timestamp: %w", err)
		}

		m.NextPage = string(marshalled)
	}

	if len(motions) > 0 && last.After(motions[0].Proposed) {
		marshalled, err := motions[0].Proposed.MarshalText()
		if err != nil {
			return fmt.Errorf("could not serialize timestamp: %w", err)
		}

		m.PrevPage = string(marshalled)
	}

	return nil
}

func (app *application) motionList(w http.ResponseWriter, r *http.Request) {
	if r.URL.Path != "/motions/" {
		app.notFound(w)

		return
	}

	var (
		listOptions *models.MotionListOptions
		err         error
	)

	listOptions, err = app.calculateMotionListOptions(r)
	if err != nil {
		app.clientError(w, http.StatusBadRequest)

		return
	}

	ctx := r.Context()

	motions, err := app.motions.GetMotions(ctx, listOptions)
	if err != nil {
		app.serverError(w, err)

		return
	}

	first, last, err := app.motions.TimestampRange(ctx, listOptions)
	if err != nil {
		app.serverError(w, err)

		return
	}

	templateData := app.newTemplateData(r, "motions", "all-motions")

	if listOptions.UnvotedOnly {
		templateData.ActiveSubNav = subLevelNavMotionsUnvoted
	}

	templateData.Motions = motions

	err = templateData.motionPaginationOptions(listOptions.Limit, first, last)
	if err != nil {
		app.serverError(w, err)

		return
	}

	app.render(w, http.StatusOK, "motions.html", templateData)
}

func (app *application) calculateMotionListOptions(r *http.Request) (*models.MotionListOptions, error) {
	const (
		queryParamBefore  = "before"
		queryParamAfter   = "after"
		queryParamUnvoted = "unvoted"
		motionsPerPage    = 10
	)

	listOptions := &models.MotionListOptions{Limit: motionsPerPage}

	if r.URL.Query().Has(queryParamAfter) {
		var after time.Time

		err := after.UnmarshalText([]byte(r.URL.Query().Get(queryParamAfter)))
		if err != nil {
			return nil, fmt.Errorf("could not unmarshal timestamp: %w", err)
		}

		listOptions.After = &after
	} else if r.URL.Query().Has(queryParamBefore) {
		var before time.Time

		err := before.UnmarshalText([]byte(r.URL.Query().Get(queryParamBefore)))
		if err != nil {
			return nil, fmt.Errorf("could not unmarshal timestamp: %w", err)
		}

		listOptions.Before = &before
	}

	if r.URL.Query().Has(queryParamUnvoted) {
		listOptions.UnvotedOnly = true

		voter, err := app.GetUser(r)
		if err != nil {
			return nil, fmt.Errorf("could not get voter: %w", err)
		}

		if voter != nil {
			listOptions.VoterID = voter.ID
		}
	}

	return listOptions, nil
}

func (app *application) motionDetails(w http.ResponseWriter, r *http.Request) {
	params := httprouter.ParamsFromContext(r.Context())

	tag := params.ByName("tag")

	showVotes := r.URL.Query().Has("showvotes")

	motion, err := app.motions.GetMotionByTag(r.Context(), tag, showVotes)
	if err != nil && !errors.Is(err, sql.ErrNoRows) {
		app.serverError(w, err)

		return
	}

	if motion == nil {
		app.notFound(w)

		return
	}

	data := app.newTemplateData(r, topLevelNavMotions, subLevelNavMotionsAll)

	data.Motion = motion

	app.render(w, http.StatusOK, "motion.html", data)
}

type NewMotionForm struct {
	Title               string           `form:"title"`
	Content             string           `form:"content"`
	Type                *models.VoteType `form:"type"`
	Due                 int              `form:"due"`
	User                *models.User     `form:"-"`
	validator.Validator `form:"-"`
}

func (app *application) newMotionForm(w http.ResponseWriter, r *http.Request) {
	data := app.newTemplateData(r, "motions", "all-motions")
	data.Form = &NewMotionForm{
		User: data.User,
		Type: models.VoteTypeMotion,
	}

	app.render(w, http.StatusOK, "create_motion.html", data)
}

func (form *NewMotionForm) Validate() {
	const (
		minimumTitleLength   = 3
		maximumTitleLength   = 200
		minimumContentLength = 3
		maximumContentLength = 8000

		threeDays  = 3
		oneWeek    = 7
		twoWeeks   = 14
		threeWeeks = 28
	)

	form.CheckField(
		validator.NotBlank(form.Title),
		"title",
		"This field cannot be blank",
	)
	form.CheckField(
		validator.MinChars(form.Title, minimumTitleLength),
		"title",
		fmt.Sprintf("This field must be at least %d characters long", minimumTitleLength),
	)
	form.CheckField(
		validator.MaxChars(form.Title, maximumTitleLength),
		"title",
		fmt.Sprintf("This field must be at most %d characters long", maximumTitleLength),
	)
	form.CheckField(
		validator.NotBlank(form.Content),
		"content",
		"This field cannot be blank",
	)
	form.CheckField(
		validator.MinChars(form.Content, minimumContentLength),
		"content",
		fmt.Sprintf("This field must be at least %d characters long", minimumContentLength),
	)
	form.CheckField(
		validator.MaxChars(form.Content, maximumContentLength),
		"content",
		fmt.Sprintf("This field must be at most %d characters long", maximumContentLength),
	)

	form.CheckField(validator.PermittedInt(
		form.Due, threeDays, oneWeek, twoWeeks, threeWeeks), "due", "invalid duration choice",
	)
}

func (app *application) newMotionSubmit(w http.ResponseWriter, r *http.Request) {
	const hoursInDay = 24

	var form NewMotionForm

	err := app.decodePostForm(r, &form)
	if err != nil {
		app.clientError(w, http.StatusBadRequest)

		return
	}

	form.Validate()

	if !form.Valid() {
		form.User = &models.User{}

		data := app.newTemplateData(r, topLevelNavMotions, subLevelNavMotionsAll)
		data.Form = form

		app.render(w, http.StatusUnprocessableEntity, "create_motion.html", data)

		return
	}

	user, err := app.GetUser(r)
	if err != nil {
		app.clientError(w, http.StatusUnauthorized)

		return
	}

	now := time.Now().UTC()
	dueDuration := time.Duration(form.Due) * hoursInDay * time.Hour

	decisionID, err := app.motions.Create(
		r.Context(),
		user,
		form.Type,
		form.Title,
		form.Content,
		now,
		now.Add(dueDuration),
	)
	if err != nil {
		app.serverError(w, err)

		return
	}

	decision, err := app.motions.GetByID(r.Context(), decisionID)
	if err != nil {
		app.serverError(w, err)

		return
	}

	app.mailNotifier.notifyChannel <- &NewDecisionNotification{
		decision: &models.NewMotion{Decision: decision, Proposer: user},
	}

	app.sessionManager.Put(r.Context(), "flash", fmt.Sprintf("Started new motion %s: %s", decision.Tag, decision.Title))

	http.Redirect(w, r, fmt.Sprintf("/motions/%s", decision.Tag), http.StatusSeeOther)
}

func (app *application) editMotionForm(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) editMotionSubmit(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) withdrawMotionForm(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) withdrawMotionSubmit(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) voteForm(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) voteSubmit(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) proxyVoteForm(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) proxyVoteSubmit(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) userList(w http.ResponseWriter, r *http.Request) {
	data := app.newTemplateData(r, topLevelNavUsers, subLevelNavUsers)

	app.render(w, http.StatusOK, "users.html", data)
}

func (app *application) submitUserRoles(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) editUserForm(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}
func (app *application) editUserSubmit(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) userAddEmailForm(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) userAddEmailSubmit(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) deleteUserForm(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}

func (app *application) deleteUserSubmit(_ http.ResponseWriter, _ *http.Request) {
	panic("not implemented")
}