package models

import (
	"context"
	"fmt"
	"strings"
	"time"

	"github.com/bluesky-social/indigo/atproto/syntax"
	"tangled.org/core/idresolver"
)

type NotificationType string

const (
	NotificationTypeRepoStarred         NotificationType = "repo_starred"
	NotificationTypeIssueCreated        NotificationType = "issue_created"
	NotificationTypeIssueCommented      NotificationType = "issue_commented"
	NotificationTypePullCreated         NotificationType = "pull_created"
	NotificationTypePullCommented       NotificationType = "pull_commented"
	NotificationTypeFollowed            NotificationType = "followed"
	NotificationTypeUserMentioned       NotificationType = "user_mentioned"
	NotificationTypeCollaboratorInvited NotificationType = "collaborator_invited"
)

// issues and pulls share one record type (org.tangled.track.ticket), so the
// kind is persisted rather than read off the entity's collection
type EntityKind string

const (
	EntityKindIssue EntityKind = "issue"
	EntityKindPull  EntityKind = "pull"
)

var SocialNotificationTypes = []NotificationType{
	NotificationTypeRepoStarred,
	NotificationTypeFollowed,
}

var WorkNotificationTypes = []NotificationType{
	NotificationTypeIssueCreated,
	NotificationTypeIssueCommented,
	NotificationTypePullCreated,
	NotificationTypePullCommented,
	NotificationTypeUserMentioned,
	NotificationTypeCollaboratorInvited,
}

// email digest types; social types (repo_starred, followed) are excluded.
var EmailNotificationTypes = []NotificationType{
	NotificationTypeIssueCreated,
	NotificationTypeIssueCommented,
	NotificationTypePullCreated,
	NotificationTypePullCommented,
	NotificationTypeUserMentioned,
}

type Notification struct {
	ID           int64
	RecipientDid string
	AtUri        string // source record (comment/ticket/star/follow); dedupe key
	Type         NotificationType
	ActorDid     string
	RepoDid      string
	KnotDid      string
	RepoName     string // not stored; filled from the repo cache when the digest reads
	EntityAt     string // related ticket at-uri (for links); source itself for tickets
	EntityKind   EntityKind
	EntityTitle  string
	Read         bool
	Emailed      bool
	Created      time.Time
}

func (n *Notification) Icon() string {
	switch n.Type {
	case NotificationTypeRepoStarred:
		return "star"
	case NotificationTypeIssueCreated:
		return "circle-dot"
	case NotificationTypeIssueCommented, NotificationTypePullCommented:
		return "message-square"
	case NotificationTypePullCreated:
		return "git-pull-request-create"
	case NotificationTypeFollowed:
		return "user-plus"
	case NotificationTypeUserMentioned:
		return "at-sign"
	case NotificationTypeCollaboratorInvited:
		return "users-round"
	default:
		return ""
	}
}

func (n *Notification) URL(res *idresolver.Resolver) string {
	resolve := func(did string) string {
		if id, err := res.ResolveIdent(context.Background(), did); err == nil && !id.Handle.IsInvalidHandle() {
			return id.Handle.String()
		}
		return did
	}

	switch n.Type {
	case NotificationTypeFollowed:
		return "/" + resolve(n.ActorDid)
	}
	if n.RepoDid == "" || n.RepoName == "" {
		return ""
	}
	repoHandle := resolve(n.RepoDid)
	slug := strings.ToLower(n.RepoName)
	switch {
	case n.EntityAt == "":
	case n.EntityKind == EntityKindIssue:
		return fmt.Sprintf("/%s/%s/issues/%s", repoHandle, slug, n.EntityAt)
	case n.EntityKind == EntityKindPull:
		return fmt.Sprintf("/%s/%s/pulls/%s", repoHandle, slug, n.EntityAt)
	}
	return fmt.Sprintf("/%s/%s", repoHandle, slug)
}

func Category(t NotificationType) string {
	for _, st := range SocialNotificationTypes {
		if st == t {
			return "social"
		}
	}
	return "work"
}

type NotificationPreferences struct {
	ID                 int64
	UserDid            syntax.DID
	RepoStarred        bool
	IssueCreated       bool
	IssueCommented     bool
	PullCreated        bool
	PullCommented      bool
	Followed           bool
	UserMentioned      bool
	EmailNotifications bool
}

func (prefs *NotificationPreferences) ShouldNotify(t NotificationType) bool {
	switch t {
	case NotificationTypeRepoStarred:
		return prefs.RepoStarred
	case NotificationTypeIssueCreated:
		return prefs.IssueCreated
	case NotificationTypeIssueCommented:
		return prefs.IssueCommented
	case NotificationTypePullCreated:
		return prefs.PullCreated
	case NotificationTypePullCommented:
		return prefs.PullCommented
	case NotificationTypeFollowed:
		return prefs.Followed
	case NotificationTypeUserMentioned:
		return prefs.UserMentioned
	default:
		return false
	}
}

func DefaultNotificationPreferences(user syntax.DID) *NotificationPreferences {
	return &NotificationPreferences{
		UserDid:            user,
		RepoStarred:        true,
		IssueCreated:       true,
		IssueCommented:     true,
		PullCreated:        true,
		PullCommented:      true,
		Followed:           true,
		UserMentioned:      true,
		EmailNotifications: false,
	}
}