// SPDX-FileCopyrightText: 2024 Dan Anglin <d.n.i.anglin@gmail.com>
//
// SPDX-License-Identifier: GPL-3.0-or-later

package model

import (
	"encoding/json"
	"fmt"
	"strings"
	"time"

	"codeflow.dananglin.me.uk/apollo/enbas/internal/utilities"
)

type NotificationType int

const (
	NotificationTypeFollow NotificationType = iota
	NotificationTypeFollowRequest
	NotificationTypeMention
	NotificationTypeReblog
	NotificationTypeFavourite
	NotificationTypePoll
	NotificationTypeStatus
	NotificationTypeUnknown
)

const (
	notificationFollow        = "follow"
	notificationFollowRequest = "follow_request"
	notificationMention       = "mention"
	notificationReblog        = "reblog"
	notificationFavourite     = "favourite"
	notificationPoll          = "poll"
	notificationStatus        = "status"
)

func (n NotificationType) MessageFormat() string {
	mapped := map[NotificationType]string{
		NotificationTypeFollow:        "%s followed you",
		NotificationTypeFollowRequest: "%s has requested to follow you",
		NotificationTypeMention:       "%s has mentioned you in this status",
		NotificationTypeReblog:        "%s reposted this status from you",
		NotificationTypeFavourite:     "%s liked this status from you",
		NotificationTypePoll:          "A poll from %s that you have voted in has ended",
		NotificationTypeStatus:        "%s has posted this status",
	}

	output, ok := mapped[n]
	if !ok {
		return "You have received a notification of an unknown type"
	}

	return output
}

func ParseNotificationType(value string) (NotificationType, error) {
	mapped := map[string]NotificationType{
		notificationFollow:        NotificationTypeFollow,
		notificationFollowRequest: NotificationTypeFollowRequest,
		notificationMention:       NotificationTypeMention,
		notificationReblog:        NotificationTypeReblog,
		notificationFavourite:     NotificationTypeFavourite,
		notificationPoll:          NotificationTypePoll,
		notificationStatus:        NotificationTypeStatus,
	}

	output, ok := mapped[value]
	if !ok {
		return NotificationTypeUnknown, UnknownNotificationError{}
	}

	return output, nil
}

func (n *NotificationType) UnmarshalJSON(data []byte) error {
	var (
		value string
		err   error
	)

	if err = json.Unmarshal(data, &value); err != nil {
		return fmt.Errorf("unable to unmarshal the data: %w", err)
	}

	// Ignore the error if the notification type from another Fediverse service
	// is not known by enbas. It will be seen as an unknown notification to the user.
	*n, _ = ParseNotificationType(value)

	return nil
}

type UnknownNotificationError struct{}

func (e UnknownNotificationError) Error() string {
	return "unknown notification type"
}

type Notification struct {
	Account   *Account         `json:"account"`
	CreatedAt time.Time        `json:"created_at"`
	ID        string           `json:"id"`
	Status    *Status          `json:"status"`
	Type      NotificationType `json:"type"`
}

func (n Notification) Display(noColor bool) string {
	var builder strings.Builder

	separator := "────────────────────────────────────────────────────────────────────────────────"

	fmt.Fprintf(&builder,
		n.Type.MessageFormat(),
		utilities.DisplayNameFormat(noColor, n.Account.DisplayName)+" (@"+n.Account.Acct+")",
	)

	if n.Status != nil {
		builder.WriteString("\n\n" + utilities.DisplayNameFormat(noColor, n.Status.Account.DisplayName) + " (@" + n.Status.Account.Acct + ")\n")
		builder.WriteString(utilities.WrapLines(utilities.ConvertHTMLToText(n.Status.Content), "\n", 80) + "\n\n")
		builder.WriteString(utilities.FieldFormat(noColor, "ID:") + " " + n.Status.ID + "\t" + utilities.FieldFormat(noColor, "Created at:") + " " + utilities.FormatTime(n.Status.CreatedAt) + "\n")
	}

	builder.WriteString(separator + "\n")

	return builder.String()
}