// GoToSocial
// Copyright (C) GoToSocial Authors admin@gotosocial.org
// SPDX-License-Identifier: AGPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program.  If not, see <http://www.gnu.org/licenses/>.

// Package gtsmodel contains types used *internally* by GoToSocial and added/removed/selected from the database.
// These types should never be serialized and/or sent out via public APIs, as they contain sensitive information.
// The annotation used on these structs is for handling them via the bun-db ORM.
// See here for more info on bun model annotations: https://bun.uptrace.dev/guide/models.html
package gtsmodel

import (
	"crypto/rsa"
	"strings"
	"time"

	"github.com/superseriousbusiness/gotosocial/internal/config"
	"github.com/superseriousbusiness/gotosocial/internal/log"
)

// Account represents either a local or a remote fediverse account, gotosocial or otherwise (mastodon, pleroma, etc).
type Account struct {
	ID                      string           `validate:"required,ulid" bun:"type:CHAR(26),pk,nullzero,notnull,unique"`                                               // id of this item in the database
	CreatedAt               time.Time        `validate:"-" bun:"type:timestamptz,nullzero,notnull,default:current_timestamp"`                                        // when was item created.
	UpdatedAt               time.Time        `validate:"-" bun:"type:timestamptz,nullzero,notnull,default:current_timestamp"`                                        // when was item was last updated.
	FetchedAt               time.Time        `validate:"required_with=Domain" bun:"type:timestamptz,nullzero"`                                                       // when was item (remote) last fetched.
	Username                string           `validate:"required" bun:",nullzero,notnull,unique:usernamedomain"`                                                     // Username of the account, should just be a string of [a-zA-Z0-9_]. Can be added to domain to create the full username in the form ``[username]@[domain]`` eg., ``user_96@example.org``. Username and domain should be unique *with* each other
	Domain                  string           `validate:"omitempty,fqdn" bun:",nullzero,unique:usernamedomain"`                                                       // Domain of the account, will be null if this is a local account, otherwise something like ``example.org``. Should be unique with username.
	AvatarMediaAttachmentID string           `validate:"omitempty,ulid" bun:"type:CHAR(26),nullzero"`                                                                // Database ID of the media attachment, if present
	AvatarMediaAttachment   *MediaAttachment `validate:"-" bun:"rel:belongs-to"`                                                                                     // MediaAttachment corresponding to avatarMediaAttachmentID
	AvatarRemoteURL         string           `validate:"omitempty,url" bun:",nullzero"`                                                                              // For a non-local account, where can the header be fetched?
	HeaderMediaAttachmentID string           `validate:"omitempty,ulid" bun:"type:CHAR(26),nullzero"`                                                                // Database ID of the media attachment, if present
	HeaderMediaAttachment   *MediaAttachment `validate:"-" bun:"rel:belongs-to"`                                                                                     // MediaAttachment corresponding to headerMediaAttachmentID
	HeaderRemoteURL         string           `validate:"omitempty,url" bun:",nullzero"`                                                                              // For a non-local account, where can the header be fetched?
	DisplayName             string           `validate:"-" bun:""`                                                                                                   // DisplayName for this account. Can be empty, then just the Username will be used for display purposes.
	EmojiIDs                []string         `validate:"dive,ulid" bun:"emojis,array"`                                                                               // Database IDs of any emojis used in this account's bio, display name, etc
	Emojis                  []*Emoji         `validate:"-" bun:"attached_emojis,m2m:account_to_emojis"`                                                              // Emojis corresponding to emojiIDs. https://bun.uptrace.dev/guide/relations.html#many-to-many-relation
	Fields                  []*Field         `validate:"-"`                                                                                                          // A slice of of fields that this account has added to their profile.
	FieldsRaw               []*Field         `validate:"-"`                                                                                                          // The raw (unparsed) content of fields that this account has added to their profile, without conversion to HTML, only available when requester = target
	Note                    string           `validate:"-" bun:""`                                                                                                   // A note that this account has on their profile (ie., the account's bio/description of themselves)
	NoteRaw                 string           `validate:"-" bun:""`                                                                                                   // The raw contents of .Note without conversion to HTML, only available when requester = target
	Memorial                *bool            `validate:"-" bun:",default:false"`                                                                                     // Is this a memorial account, ie., has the user passed away?
	AlsoKnownAs             string           `validate:"omitempty,ulid" bun:"type:CHAR(26),nullzero"`                                                                // This account is associated with x account id (TODO: migrate to be AlsoKnownAsID)
	MovedToAccountID        string           `validate:"omitempty,ulid" bun:"type:CHAR(26),nullzero"`                                                                // This account has moved this account id in the database
	Bot                     *bool            `validate:"-" bun:",default:false"`                                                                                     // Does this account identify itself as a bot?
	Reason                  string           `validate:"-" bun:""`                                                                                                   // What reason was given for signing up when this account was created?
	Locked                  *bool            `validate:"-" bun:",default:true"`                                                                                      // Does this account need an approval for new followers?
	Discoverable            *bool            `validate:"-" bun:",default:false"`                                                                                     // Should this account be shown in the instance's profile directory?
	Privacy                 Visibility       `validate:"required_without=Domain,omitempty,oneof=public unlocked followers_only mutuals_only direct" bun:",nullzero"` // Default post privacy for this account
	Sensitive               *bool            `validate:"-" bun:",default:false"`                                                                                     // Set posts from this account to sensitive by default?
	Language                string           `validate:"omitempty,bcp47_language_tag" bun:",nullzero,notnull,default:'en'"`                                          // What language does this account post in?
	StatusContentType       string           `validate:"required_without=Domain,omitempty,oneof=text/plain text/markdown" bun:",nullzero"`                           // What is the default format for statuses posted by this account (only for local accounts).
	CustomCSS               string           `validate:"-" bun:",nullzero"`                                                                                          // Custom CSS that should be displayed for this Account's profile and statuses.
	URI                     string           `validate:"required,url" bun:",nullzero,notnull,unique"`                                                                // ActivityPub URI for this account.
	URL                     string           `validate:"required_without=Domain,omitempty,url" bun:",nullzero,unique"`                                               // Web URL for this account's profile
	InboxURI                string           `validate:"required_without=Domain,omitempty,url" bun:",nullzero,unique"`                                               // Address of this account's ActivityPub inbox, for sending activity to
	SharedInboxURI          *string          `validate:"-" bun:""`                                                                                                   // Address of this account's ActivityPub sharedInbox. Gotcha warning: this is a string pointer because it has three possible states: 1. We don't know yet if the account has a shared inbox -- null. 2. We know it doesn't have a shared inbox -- empty string. 3. We know it does have a shared inbox -- url string.
	OutboxURI               string           `validate:"required_without=Domain,omitempty,url" bun:",nullzero,unique"`                                               // Address of this account's activitypub outbox
	FollowingURI            string           `validate:"required_without=Domain,omitempty,url" bun:",nullzero,unique"`                                               // URI for getting the following list of this account
	FollowersURI            string           `validate:"required_without=Domain,omitempty,url" bun:",nullzero,unique"`                                               // URI for getting the followers list of this account
	FeaturedCollectionURI   string           `validate:"required_without=Domain,omitempty,url" bun:",nullzero,unique"`                                               // URL for getting the featured collection list of this account
	ActorType               string           `validate:"oneof=Application Group Organization Person Service" bun:",nullzero,notnull"`                                // What type of activitypub actor is this account?
	PrivateKey              *rsa.PrivateKey  `validate:"required_without=Domain" bun:""`                                                                             // Privatekey for validating activitypub requests, will only be defined for local accounts
	PublicKey               *rsa.PublicKey   `validate:"required" bun:",notnull"`                                                                                    // Publickey for encoding activitypub requests, will be defined for both local and remote accounts
	PublicKeyURI            string           `validate:"required,url" bun:",nullzero,notnull,unique"`                                                                // Web-reachable location of this account's public key
	SensitizedAt            time.Time        `validate:"-" bun:"type:timestamptz,nullzero"`                                                                          // When was this account set to have all its media shown as sensitive?
	SilencedAt              time.Time        `validate:"-" bun:"type:timestamptz,nullzero"`                                                                          // When was this account silenced (eg., statuses only visible to followers, not public)?
	SuspendedAt             time.Time        `validate:"-" bun:"type:timestamptz,nullzero"`                                                                          // When was this account suspended (eg., don't allow it to log in/post, don't accept media/posts from this account)
	HideCollections         *bool            `validate:"-" bun:",default:false"`                                                                                     // Hide this account's collections
	SuspensionOrigin        string           `validate:"omitempty,ulid" bun:"type:CHAR(26),nullzero"`                                                                // id of the database entry that caused this account to become suspended -- can be an account ID or a domain block ID
	EnableRSS               *bool            `validate:"-" bun:",default:false"`                                                                                     // enable RSS feed subscription for this account's public posts at [URL]/feed
}

// IsLocal returns whether account is a local user account.
func (a *Account) IsLocal() bool {
	return a.Domain == "" || a.Domain == config.GetHost() || a.Domain == config.GetAccountDomain()
}

// IsRemote returns whether account is a remote user account.
func (a *Account) IsRemote() bool {
	return !a.IsLocal()
}

// IsInstance returns whether account is an instance internal actor account.
func (a *Account) IsInstance() bool {
	if a.IsLocal() {
		// Check if our instance account.
		return a.Username == config.GetHost()
	}

	// Check if remote instance account.
	return a.Username == a.Domain ||
		a.FollowersURI == "" ||
		a.FollowingURI == "" ||
		(a.Username == "internal.fetch" && strings.Contains(a.Note, "internal service actor")) ||
		a.Username == "instance.actor" // <- misskey
}

// EmojisPopulated returns whether emojis are populated according to current EmojiIDs.
func (a *Account) EmojisPopulated() bool {
	if len(a.EmojiIDs) != len(a.Emojis) {
		// this is the quickest indicator.
		return false
	}

	// Emojis must be in same order.
	for i, id := range a.EmojiIDs {
		if a.Emojis[i] == nil {
			log.Warnf(nil, "nil emoji in slice for account %s", a.URI)
			continue
		}
		if a.Emojis[i].ID != id {
			return false
		}
	}

	return true
}

// AccountToEmoji is an intermediate struct to facilitate the many2many relationship between an account and one or more emojis.
type AccountToEmoji struct {
	AccountID string   `validate:"ulid,required" bun:"type:CHAR(26),unique:accountemoji,nullzero,notnull"`
	Account   *Account `validate:"-" bun:"rel:belongs-to"`
	EmojiID   string   `validate:"ulid,required" bun:"type:CHAR(26),unique:accountemoji,nullzero,notnull"`
	Emoji     *Emoji   `validate:"-" bun:"rel:belongs-to"`
}

// Field represents a key value field on an account, for things like pronouns, website, etc.
// VerifiedAt is optional, to be used only if Value is a URL to a webpage that contains the
// username of the user.
type Field struct {
	Name       string    `validate:"required"`          // Name of this field.
	Value      string    `validate:"required"`          // Value of this field.
	VerifiedAt time.Time `validate:"-" bun:",nullzero"` // This field was verified at (optional).
}

// Relationship describes a requester's relationship with another account.
type Relationship struct {
	ID                  string // The account id.
	Following           bool   // Are you following this user?
	ShowingReblogs      bool   // Are you receiving this user's boosts in your home timeline?
	Notifying           bool   // Have you enabled notifications for this user?
	FollowedBy          bool   // Are you followed by this user?
	Blocking            bool   // Are you blocking this user?
	BlockedBy           bool   // Is this user blocking you?
	Muting              bool   // Are you muting this user?
	MutingNotifications bool   // Are you muting notifications from this user?
	Requested           bool   // Do you have a pending follow request for this user?
	DomainBlocking      bool   // Are you blocking this user's domain?
	Endorsed            bool   // Are you featuring this user on your profile?
	Note                string // Your note on this account.
}