Files
x/blogo/plugins/foldingrenderer.go

150 lines
3.0 KiB
Go

// Copyright 2025-present Gustavo "Guz" L. de Mello
// Copyright 2025-present The Lored.dev Contributors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package plugins
import (
"bytes"
"fmt"
"io"
"io/fs"
"log/slog"
"forge.capytal.company/loreddev/x/blogo/plugin"
)
const foldingRendererPluginName = "blogo-foldingrenderer-renderer"
type foldingRenderer struct {
plugins []plugin.Renderer
panicOnInit bool
log *slog.Logger
}
type FoldingRendererOpts struct {
PanicOnInit bool
Logger *slog.Logger
}
type FoldingRenderer interface {
plugin.WithPlugins
plugin.Renderer
}
func NewFoldingRenderer(opts ...FoldingRendererOpts) FoldingRenderer {
opt := FoldingRendererOpts{}
if len(opts) > 0 {
opt = opts[0]
}
if opt.Logger == nil {
opt.Logger = slog.New(slog.NewTextHandler(io.Discard, &slog.HandlerOptions{}))
}
opt.Logger = opt.Logger.WithGroup(foldingRendererPluginName)
return &foldingRenderer{
plugins: []plugin.Renderer{},
log: opt.Logger,
}
}
func (r *foldingRenderer) Name() string {
return foldingRendererPluginName
}
func (r *foldingRenderer) Use(p plugin.Plugin) {
log := r.log.With(slog.String("plugin", p.Name()))
if pr, ok := p.(plugin.Renderer); ok {
r.plugins = append(r.plugins, pr)
} else {
m := fmt.Sprintf("failed to add plugin %q, since it doesn't implement plugin.Renderer", p.Name())
log.Error(m)
if r.panicOnInit {
panic(fmt.Sprintf("%s: %s", foldingRendererPluginName, m))
}
}
}
func (r *foldingRenderer) Render(src fs.File, w io.Writer) error {
if len(r.plugins) == 0 {
_, err := io.Copy(w, src)
return err
}
f, err := newFoldignFile(src)
if err != nil {
return err
}
for _, p := range r.plugins {
err := p.Render(f, f)
if err != nil {
return err
}
if err := f.Fold(); err != nil {
return err
}
}
_, err = io.Copy(w, f)
return err
}
type foldingFile struct {
fs.File
read *bytes.Buffer
writer *bytes.Buffer
}
func newFoldignFile(f fs.File) (*foldingFile, error) {
var r, w bytes.Buffer
if _, err := io.Copy(&r, f); err != nil {
return nil, err
}
if err := f.Close(); err != nil {
return nil, err
}
return &foldingFile{File: f, read: &r, writer: &w}, nil
}
func (f *foldingFile) Close() error {
return nil
}
func (f *foldingFile) Read(p []byte) (int, error) {
return f.read.Read(p)
}
func (f *foldingFile) Write(p []byte) (int, error) {
return f.writer.Write(p)
}
func (f *foldingFile) Fold() error {
f.read.Reset()
if _, err := io.Copy(f.writer, f.read); err != nil {
return err
}
f.writer.Reset()
return nil
}