Block/unblock (#96)

* remote + local block logic, incl. federation

* improve blocking stuff

* fiddle with display of blocked profiles

* go fmt

4 files changed, 239 insertions, 2 deletions

diff --git a/internal/processing/account/account.go b/internal/processing/account/account.go
index efdac5d3e..7b8910149 100644
--- a/internal/processing/account/account.go
+++ b/internal/processing/account/account.go
@@ -59,6 +59,11 @@ type Processor interface {
 	FollowCreate(requestingAccount *gtsmodel.Account, form *apimodel.AccountFollowRequest) (*apimodel.Relationship, gtserror.WithCode)
 	// FollowRemove handles the removal of a follow/follow request to an account, either remote or local.
 	FollowRemove(requestingAccount *gtsmodel.Account, targetAccountID string) (*apimodel.Relationship, gtserror.WithCode)
+	// BlockCreate handles the creation of a block from requestingAccount to targetAccountID, either remote or local.
+	BlockCreate(requestingAccount *gtsmodel.Account, targetAccountID string) (*apimodel.Relationship, gtserror.WithCode)
+	// BlockRemove handles the removal of a block from requestingAccount to targetAccountID, either remote or local.
+	BlockRemove(requestingAccount *gtsmodel.Account, targetAccountID string) (*apimodel.Relationship, gtserror.WithCode)
+
 	// UpdateHeader does the dirty work of checking the header part of an account update form,
 	// parsing and checking the image, and doing the necessary updates in the database for this to become
 	// the account's new header image.
diff --git a/internal/processing/account/createblock.go b/internal/processing/account/createblock.go
new file mode 100644
index 000000000..79ce03805
--- /dev/null
+++ b/internal/processing/account/createblock.go
@@ -0,0 +1,155 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   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 account
+
+import (
+	"fmt"
+
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+	"github.com/superseriousbusiness/gotosocial/internal/id"
+	"github.com/superseriousbusiness/gotosocial/internal/util"
+)
+
+func (p *processor) BlockCreate(requestingAccount *gtsmodel.Account, targetAccountID string) (*apimodel.Relationship, gtserror.WithCode) {
+	// make sure the target account actually exists in our db
+	targetAcct := &gtsmodel.Account{}
+	if err := p.db.GetByID(targetAccountID, targetAcct); err != nil {
+		if _, ok := err.(db.ErrNoEntries); ok {
+			return nil, gtserror.NewErrorNotFound(fmt.Errorf("BlockCreate: account %s not found in the db: %s", targetAccountID, err))
+		}
+	}
+
+	// if requestingAccount already blocks target account, we don't need to do anything
+	block := &gtsmodel.Block{}
+	if err := p.db.GetWhere([]db.Where{
+		{Key: "account_id", Value: requestingAccount.ID},
+		{Key: "target_account_id", Value: targetAccountID},
+	}, block); err == nil {
+		// block already exists, just return relationship
+		return p.RelationshipGet(requestingAccount, targetAccountID)
+	}
+
+	// make the block
+	newBlockID, err := id.NewULID()
+	if err != nil {
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+	block.ID = newBlockID
+	block.AccountID = requestingAccount.ID
+	block.Account = requestingAccount
+	block.TargetAccountID = targetAccountID
+	block.TargetAccount = targetAcct
+	block.URI = util.GenerateURIForBlock(requestingAccount.Username, p.config.Protocol, p.config.Host, newBlockID)
+
+	// whack it in the database
+	if err := p.db.Put(block); err != nil {
+		return nil, gtserror.NewErrorInternalError(fmt.Errorf("BlockCreate: error creating block in db: %s", err))
+	}
+
+	// clear any follows or follow requests from the blocked account to the target account -- this is a simple delete
+	if err := p.db.DeleteWhere([]db.Where{
+		{Key: "account_id", Value: targetAccountID},
+		{Key: "target_account_id", Value: requestingAccount.ID},
+	}, &gtsmodel.Follow{}); err != nil {
+		return nil, gtserror.NewErrorInternalError(fmt.Errorf("BlockCreate: error removing follow in db: %s", err))
+	}
+	if err := p.db.DeleteWhere([]db.Where{
+		{Key: "account_id", Value: targetAccountID},
+		{Key: "target_account_id", Value: requestingAccount.ID},
+	}, &gtsmodel.FollowRequest{}); err != nil {
+		return nil, gtserror.NewErrorInternalError(fmt.Errorf("BlockCreate: error removing follow in db: %s", err))
+	}
+
+	// clear any follows or follow requests from the requesting account to the target account --
+	// this might require federation so we need to pass some messages around
+
+	// check if a follow request exists from the requesting account to the target account, and remove it if it does (storing the URI for later)
+	var frChanged bool
+	var frURI string
+	fr := &gtsmodel.FollowRequest{}
+	if err := p.db.GetWhere([]db.Where{
+		{Key: "account_id", Value: requestingAccount.ID},
+		{Key: "target_account_id", Value: targetAccountID},
+	}, fr); err == nil {
+		frURI = fr.URI
+		if err := p.db.DeleteByID(fr.ID, fr); err != nil {
+			return nil, gtserror.NewErrorInternalError(fmt.Errorf("BlockCreate: error removing follow request from db: %s", err))
+		}
+		frChanged = true
+	}
+
+	// now do the same thing for any existing follow
+	var fChanged bool
+	var fURI string
+	f := &gtsmodel.Follow{}
+	if err := p.db.GetWhere([]db.Where{
+		{Key: "account_id", Value: requestingAccount.ID},
+		{Key: "target_account_id", Value: targetAccountID},
+	}, f); err == nil {
+		fURI = f.URI
+		if err := p.db.DeleteByID(f.ID, f); err != nil {
+			return nil, gtserror.NewErrorInternalError(fmt.Errorf("BlockCreate: error removing follow from db: %s", err))
+		}
+		fChanged = true
+	}
+
+	// follow request status changed so send the UNDO activity to the channel for async processing
+	if frChanged {
+		p.fromClientAPI <- gtsmodel.FromClientAPI{
+			APObjectType:   gtsmodel.ActivityStreamsFollow,
+			APActivityType: gtsmodel.ActivityStreamsUndo,
+			GTSModel: &gtsmodel.Follow{
+				AccountID:       requestingAccount.ID,
+				TargetAccountID: targetAccountID,
+				URI:             frURI,
+			},
+			OriginAccount: requestingAccount,
+			TargetAccount: targetAcct,
+		}
+	}
+
+	// follow status changed so send the UNDO activity to the channel for async processing
+	if fChanged {
+		p.fromClientAPI <- gtsmodel.FromClientAPI{
+			APObjectType:   gtsmodel.ActivityStreamsFollow,
+			APActivityType: gtsmodel.ActivityStreamsUndo,
+			GTSModel: &gtsmodel.Follow{
+				AccountID:       requestingAccount.ID,
+				TargetAccountID: targetAccountID,
+				URI:             fURI,
+			},
+			OriginAccount: requestingAccount,
+			TargetAccount: targetAcct,
+		}
+	}
+
+	// handle the rest of the block process asynchronously
+	p.fromClientAPI <- gtsmodel.FromClientAPI{
+		APObjectType:   gtsmodel.ActivityStreamsBlock,
+		APActivityType: gtsmodel.ActivityStreamsCreate,
+		GTSModel:       block,
+		OriginAccount:  requestingAccount,
+		TargetAccount:  targetAcct,
+	}
+
+	return p.RelationshipGet(requestingAccount, targetAccountID)
+}
diff --git a/internal/processing/account/get.go b/internal/processing/account/get.go
index aba1ed14a..b937ace5b 100644
--- a/internal/processing/account/get.go
+++ b/internal/processing/account/get.go
@@ -45,9 +45,19 @@ func (p *processor) Get(requestingAccount *gtsmodel.Account, targetAccountID str
 		p.log.WithField("func", "AccountGet").Debugf("dereferencing account: %s", err)
 	}
 
-	var mastoAccount *apimodel.Account
+	var blocked bool
 	var err error
-	if requestingAccount != nil && targetAccount.ID == requestingAccount.ID {
+	if requestingAccount != nil {
+		blocked, err = p.db.Blocked(requestingAccount.ID, targetAccountID)
+		if err != nil {
+			return nil, fmt.Errorf("error checking account block: %s", err)
+		}
+	}
+
+	var mastoAccount *apimodel.Account
+	if blocked {
+		mastoAccount, err = p.tc.AccountToMastoBlocked(targetAccount)
+	} else if requestingAccount != nil && targetAccount.ID == requestingAccount.ID {
 		mastoAccount, err = p.tc.AccountToMastoSensitive(targetAccount)
 	} else {
 		mastoAccount, err = p.tc.AccountToMastoPublic(targetAccount)
diff --git a/internal/processing/account/removeblock.go b/internal/processing/account/removeblock.go
new file mode 100644
index 000000000..03b0c6750
--- /dev/null
+++ b/internal/processing/account/removeblock.go
@@ -0,0 +1,67 @@
+/*
+   GoToSocial
+   Copyright (C) 2021 GoToSocial Authors admin@gotosocial.org
+
+   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 account
+
+import (
+	"fmt"
+
+	apimodel "github.com/superseriousbusiness/gotosocial/internal/api/model"
+	"github.com/superseriousbusiness/gotosocial/internal/db"
+	"github.com/superseriousbusiness/gotosocial/internal/gtserror"
+	"github.com/superseriousbusiness/gotosocial/internal/gtsmodel"
+)
+
+func (p *processor) BlockRemove(requestingAccount *gtsmodel.Account, targetAccountID string) (*apimodel.Relationship, gtserror.WithCode) {
+	// make sure the target account actually exists in our db
+	targetAcct := &gtsmodel.Account{}
+	if err := p.db.GetByID(targetAccountID, targetAcct); err != nil {
+		if _, ok := err.(db.ErrNoEntries); ok {
+			return nil, gtserror.NewErrorNotFound(fmt.Errorf("BlockRemove: account %s not found in the db: %s", targetAccountID, err))
+		}
+	}
+
+	// check if a block exists, and remove it if it does (storing the URI for later)
+	var blockChanged bool
+	block := &gtsmodel.Block{}
+	if err := p.db.GetWhere([]db.Where{
+		{Key: "account_id", Value: requestingAccount.ID},
+		{Key: "target_account_id", Value: targetAccountID},
+	}, block); err == nil {
+		block.Account = requestingAccount
+		block.TargetAccount = targetAcct
+		if err := p.db.DeleteByID(block.ID, &gtsmodel.Block{}); err != nil {
+			return nil, gtserror.NewErrorInternalError(fmt.Errorf("BlockRemove: error removing block from db: %s", err))
+		}
+		blockChanged = true
+	}
+
+	// block status changed so send the UNDO activity to the channel for async processing
+	if blockChanged {
+		p.fromClientAPI <- gtsmodel.FromClientAPI{
+			APObjectType:   gtsmodel.ActivityStreamsBlock,
+			APActivityType: gtsmodel.ActivityStreamsUndo,
+			GTSModel:       block,
+			OriginAccount:  requestingAccount,
+			TargetAccount:  targetAcct,
+		}
+	}
+
+	// return whatever relationship results from all this
+	return p.RelationshipGet(requestingAccount, targetAccountID)
+}