Timeline improvements (#41)

Tidying up.
Parent/child statuses now display correctly in status/id/context.

internal/processing/synchronous/status/context.go

@@ -1,14 +1,69 @@
 package status
 
 import (
+	"fmt"
+	"sort"
+
 	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) Context(account *gtsmodel.Account, targetStatusID string) (*apimodel.Context, gtserror.WithCode) {
-	return &apimodel.Context{
+
+	context := &apimodel.Context{
 		Ancestors:   []apimodel.Status{},
 		Descendants: []apimodel.Status{},
-	}, nil
+	}
+
+	targetStatus := &gtsmodel.Status{}
+	if err := p.db.GetByID(targetStatusID, targetStatus); err != nil {
+		if _, ok := err.(db.ErrNoEntries); ok {
+			return nil, gtserror.NewErrorNotFound(err)
+		}
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+
+	visible, err := p.filter.StatusVisible(targetStatus, account)
+	if err != nil {
+		return nil, gtserror.NewErrorNotFound(err)
+	}
+	if !visible {
+		return nil, gtserror.NewErrorForbidden(fmt.Errorf("account with id %s does not have permission to view status %s", account.ID, targetStatusID))
+	}
+
+	parents, err := p.db.StatusParents(targetStatus)
+	if err != nil {
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+
+	for _, status := range parents {
+		if v, err := p.filter.StatusVisible(status, account); err == nil && v {
+			mastoStatus, err := p.tc.StatusToMasto(status, account)
+			if err == nil {
+				context.Ancestors = append(context.Ancestors, *mastoStatus)
+			}
+		}
+	}
+
+	sort.Slice(context.Ancestors, func(i int, j int) bool {
+		return context.Ancestors[i].ID < context.Ancestors[j].ID
+	})
+
+	children, err := p.db.StatusChildren(targetStatus)
+	if err != nil {
+		return nil, gtserror.NewErrorInternalError(err)
+	}
+
+	for _, status := range children {
+		if v, err := p.filter.StatusVisible(status, account); err == nil && v {
+			mastoStatus, err := p.tc.StatusToMasto(status, account)
+			if err == nil {
+				context.Descendants = append(context.Descendants, *mastoStatus)
+			}
+		}
+	}
+
+	return context, nil
 }