feat(releasepr): release PRs can be updated

- PR Description
- Read prefix+suffix from PR description and put into changelog
- Keep those overrides on PR description changes
- Add pending level to new PRs

releasepr.go

@@ -1,13 +1,34 @@
 package rp
 
 import (
+	"bytes"
+	_ "embed"
 	"fmt"
+	"log"
+	"text/template"
 
 	"github.com/yuin/goldmark/ast"
-	"github.com/yuin/goldmark/parser"
 	"github.com/yuin/goldmark/text"
+
+	"github.com/apricote/releaser-pleaser/internal/markdown"
+	east "github.com/apricote/releaser-pleaser/internal/markdown/extensions/ast"
 )
 
+var (
+	releasePRTemplate *template.Template
+)
+
+//go:embed releasepr.md.tpl
+var rawReleasePRTemplate string
+
+func init() {
+	var err error
+	releasePRTemplate, err = template.New("releasepr").Parse(rawReleasePRTemplate)
+	if err != nil {
+		log.Fatalf("failed to parse release pr template: %v", err)
+	}
+}
+
 type ReleasePullRequest struct {
 	ID          int
 	Title       string
@@ -17,6 +38,20 @@ type ReleasePullRequest struct {
 	Head string
 }
 
+func NewReleasePullRequest(head, branch, version, changelogEntry string) (*ReleasePullRequest, error) {
+	rp := &ReleasePullRequest{
+		Head:   head,
+		Labels: []string{LabelReleasePending},
+	}
+
+	rp.SetTitle(branch, version)
+	if err := rp.SetDescription(changelogEntry); err != nil {
+		return nil, err
+	}
+
+	return rp, nil
+}
+
 type ReleaseOverrides struct {
 	Prefix string
 	Suffix string
@@ -57,6 +92,9 @@ const (
 	LabelNextVersionTypeRC     = "rp-next-version::rc"
 	LabelNextVersionTypeBeta   = "rp-next-version::beta"
 	LabelNextVersionTypeAlpha  = "rp-next-version::alpha"
+
+	LabelReleasePending = "rp-release::pending"
+	LabelReleaseTagged  = "rp-release::tagged"
 )
 
 const (
@@ -64,6 +102,10 @@ const (
 	DescriptionLanguageSuffix = "rp-suffix"
 )
 
+const (
+	MarkdownSectionOverrides = "overrides"
+)
+
 func (pr *ReleasePullRequest) GetOverrides() (ReleaseOverrides, error) {
 	overrides := ReleaseOverrides{}
 	overrides = pr.parseVersioningFlags(overrides)
@@ -95,7 +137,7 @@ func (pr *ReleasePullRequest) parseVersioningFlags(overrides ReleaseOverrides) R
 
 func (pr *ReleasePullRequest) parseDescription(overrides ReleaseOverrides) (ReleaseOverrides, error) {
 	source := []byte(pr.Description)
-	descriptionAST := parser.NewParser().Parse(text.NewReader(source))
+	descriptionAST := markdown.New().Parser().Parse(text.NewReader(source))
 
 	err := ast.Walk(descriptionAST, func(n ast.Node, entering bool) (ast.WalkStatus, error) {
 		if !entering {
@@ -127,6 +169,51 @@ func (pr *ReleasePullRequest) parseDescription(overrides ReleaseOverrides) (Rele
 	return overrides, nil
 }
 
+func (pr *ReleasePullRequest) getCurrentOverridesText() (string, error) {
+	source := []byte(pr.Description)
+	gm := markdown.New()
+	descriptionAST := gm.Parser().Parse(text.NewReader(source))
+
+	var section *east.Section
+
+	err := ast.Walk(descriptionAST, func(n ast.Node, entering bool) (ast.WalkStatus, error) {
+		if !entering {
+			return ast.WalkContinue, nil
+		}
+
+		if n.Type() != ast.TypeBlock || n.Kind() != east.KindSection {
+			return ast.WalkContinue, nil
+		}
+
+		anySection, ok := n.(*east.Section)
+		if !ok {
+			return ast.WalkStop, fmt.Errorf("node has unexpected type: %T", n)
+		}
+
+		if anySection.Name != MarkdownSectionOverrides {
+			return ast.WalkContinue, nil
+		}
+
+		section = anySection
+		return ast.WalkStop, nil
+	})
+	if err != nil {
+		return "", err
+	}
+
+	if section == nil {
+		return "", nil
+	}
+
+	outputBuffer := new(bytes.Buffer)
+	err = gm.Renderer().Render(outputBuffer, source, section)
+	if err != nil {
+		return "", err
+	}
+
+	return outputBuffer.String(), nil
+}
+
 func textFromLines(source []byte, n ast.Node) string {
 	content := make([]byte, 0)
 
@@ -137,5 +224,28 @@ func textFromLines(source []byte, n ast.Node) string {
 	}
 
 	return string(content)
-
+}
+
+func (pr *ReleasePullRequest) SetTitle(branch, version string) {
+	pr.Title = fmt.Sprintf("chore(%s): release %s", branch, version)
+}
+
+func (pr *ReleasePullRequest) SetDescription(changelogEntry string) error {
+	overrides, err := pr.getCurrentOverridesText()
+	if err != nil {
+		return err
+	}
+
+	var description bytes.Buffer
+	err = releasePRTemplate.Execute(&description, map[string]any{
+		"Changelog": changelogEntry,
+		"Overrides": overrides,
+	})
+	if err != nil {
+		return err
+	}
+
+	pr.Description = description.String()
+
+	return nil
 }