[chore] Refactor account deleting/block logic, tidy up some other processing things (#1599)

* start refactoring account deletion

* update to use state.DB

* further messing about

* some more tidying up

* more tidying, cleaning, nice-making

* further adventures in refactoring and the woes of technical debt

* update fr accept/reject

* poking + prodding

* fix up deleting

* create fave uri

* don't log using requestingAccount.ID because it might be nil

* move getBookmarks function

* use exists query to check for status bookmark

* use deletenotifications func

* fiddle

* delete follow request notif

* split up some db functions

* Fix possible nil pointer panic

* fix more possible nil pointers

* fix license headers

* warn when follow missing (target) account

* return wrapped err when bookmark/fave models can't be retrieved

* simplify self account delete

* warn log likely race condition

* de-sillify status delete loop

* move error check due north

* warn when unfollowSideEffects has no target account

* warn when no boost account is found

* warn + dump follow when no account

* more warnings

* warn on fave account not set

* move for loop inside anonymous function

* fix funky logic

* don't remove mutual account items on block;
do make sure unfollow occurs in both directions!

1 files changed, 51 insertions, 12 deletions

diff --git a/internal/db/relationship.go b/internal/db/relationship.go
index 643a5696a..d13a73dea 100644
--- a/internal/db/relationship.go
+++ b/internal/db/relationship.go
@@ -73,22 +73,61 @@ type Relationship interface {
 	// The deleted follow request will be returned so that further processing can be done on it.
 	RejectFollowRequest(ctx context.Context, originAccountID string, targetAccountID string) (*gtsmodel.FollowRequest, Error)
 
-	// GetAccountFollowRequests returns all follow requests targeting the given account.
-	GetAccountFollowRequests(ctx context.Context, accountID string) ([]*gtsmodel.FollowRequest, Error)
+	// GetFollows returns a slice of follows owned by the given accountID, and/or
+	// targeting the given account id.
+	//
+	// If accountID is set and targetAccountID isn't, then all follows created by
+	// accountID will be returned.
+	//
+	// If targetAccountID is set and accountID isn't, then all follows targeting
+	// targetAccountID will be returned.
+	//
+	// If both accountID and targetAccountID are set, then only 0 or 1 follows will
+	// be in the returned slice.
+	GetFollows(ctx context.Context, accountID string, targetAccountID string) ([]*gtsmodel.Follow, Error)
 
-	// GetAccountFollows returns a slice of follows owned by the given accountID.
-	GetAccountFollows(ctx context.Context, accountID string) ([]*gtsmodel.Follow, Error)
+	// GetLocalFollowersIDs returns a list of local account IDs which follow the
+	// targetAccountID. The returned IDs are not guaranteed to be ordered in any
+	// particular way, so take care.
+	GetLocalFollowersIDs(ctx context.Context, targetAccountID string) ([]string, Error)
 
-	// CountAccountFollows returns the amount of accounts that the given accountID is following.
+	// CountFollows is like GetFollows, but just counts rather than returning.
+	CountFollows(ctx context.Context, accountID string, targetAccountID string) (int, Error)
+
+	// GetFollowRequests returns a slice of follows requests owned by the given
+	// accountID, and/or targeting the given account id.
+	//
+	// If accountID is set and targetAccountID isn't, then all requests created by
+	// accountID will be returned.
 	//
-	// If localOnly is set to true, then only follows from *this instance* will be returned.
-	CountAccountFollows(ctx context.Context, accountID string, localOnly bool) (int, Error)
+	// If targetAccountID is set and accountID isn't, then all requests targeting
+	// targetAccountID will be returned.
+	//
+	// If both accountID and targetAccountID are set, then only 0 or 1 requests will
+	// be in the returned slice.
+	GetFollowRequests(ctx context.Context, accountID string, targetAccountID string) ([]*gtsmodel.FollowRequest, Error)
+
+	// CountFollowRequests is like GetFollowRequests, but just counts rather than returning.
+	CountFollowRequests(ctx context.Context, accountID string, targetAccountID string) (int, Error)
 
-	// GetAccountFollowedBy fetches follows that target given accountID.
+	// Unfollow removes a follow targeting targetAccountID and originating
+	// from originAccountID.
+	//
+	// If a follow was removed this way, the AP URI of the follow will be
+	// returned to the caller, so that further processing can take place
+	// if necessary.
 	//
-	// If localOnly is set to true, then only follows from *this instance* will be returned.
-	GetAccountFollowedBy(ctx context.Context, accountID string, localOnly bool) ([]*gtsmodel.Follow, Error)
+	// If no follow was removed this way, the returned string will be empty.
+	Unfollow(ctx context.Context, originAccountID string, targetAccountID string) (string, Error)
 
-	// CountAccountFollowedBy returns the amounts that the given ID is followed by.
-	CountAccountFollowedBy(ctx context.Context, accountID string, localOnly bool) (int, Error)
+	// UnfollowRequest removes a follow request targeting targetAccountID
+	// and originating from originAccountID.
+	//
+	// If a follow request was removed this way, the AP URI of the follow
+	// request will be returned to the caller, so that further processing
+	// can take place if necessary.
+	//
+	// If no follow request was removed this way, the returned string will
+	// be empty.
+	UnfollowRequest(ctx context.Context, originAccountID string, targetAccountID string) (string, Error)
 }