From 49ac37ce8f9dc84aabd9da0973bed8089ad85175 Mon Sep 17 00:00:00 2001
From: Gahan Rakholia <gahan94rakh@gmail.com>
Date: Sun, 12 Nov 2023 14:42:41 +0530
Subject: [PATCH] add factory function for PR and commit populator

---
 cmd/generate.go                                  |  7 +++++--
 pkg/jira_changelog/generator.go                  | 16 ++++++++--------
 pkg/jira_changelog/generator_test.go             |  2 +-
 .../messages/git_commits_populator.go            |  4 ++--
 pkg/jira_changelog/messages/populator.go         | 16 +++++++++++++++-
 5 files changed, 31 insertions(+), 14 deletions(-)

diff --git a/cmd/generate.go b/cmd/generate.go
index 4118ec6..680ab92 100644
--- a/cmd/generate.go
+++ b/cmd/generate.go
@@ -18,6 +18,7 @@ var (
 	fromRef        string
 	toRef          string
 	writeTo        string
+	usePR          bool
 	DefaultTimeout = 10 * time.Second
 )
 
@@ -62,11 +63,12 @@ gh jira-changelog generate --config="<path-to-config-file>.yaml" --from="v0.1.0"
 		defer cancel()
 
 		changelog := jira_changelog.NewGenerator(
-			jira.NewContext(jira.Options{
+			jira.NewClient(jira.NewContext(jira.Options{
 				jira.BaseURL:  viper.GetString("base_url"),
 				jira.ApiToken: viper.GetString("api_token"),
 				jira.User:     viper.GetString("email_id"),
-			}),
+			})),
+			usePR,
 			fromRef,
 			toRef,
 			viper.GetString("repo_url"),
@@ -100,6 +102,7 @@ func writer(writeTo string) io.Writer {
 func init() {
 	generateCmd.Flags().StringVar(&fromRef, "from", "", "Git ref to start from")
 	generateCmd.Flags().StringVar(&toRef, "to", "main", "Git ref to end at")
+	generateCmd.Flags().BoolVar(&usePR, "use_pr", false, "use PR titles to generate changelog. Note: only works if used as gh plugin")
 	generateCmd.Flags().StringVar(&writeTo, "write_to", "/dev/stdout", "File stream to write the changelog")
 
 	generateCmd.MarkFlagRequired("from")
diff --git a/pkg/jira_changelog/generator.go b/pkg/jira_changelog/generator.go
index 0b54ae1..1f26d6b 100644
--- a/pkg/jira_changelog/generator.go
+++ b/pkg/jira_changelog/generator.go
@@ -15,23 +15,23 @@ type Generator struct {
 	toRef      string
 	repoURL    string
 	client     jira.Client
+	usePR      bool
 }
 
-func NewGenerator(jiraCtx *jira.Context, fromRef, toRef, repoURL string) *Generator {
-	client := jira.NewClient(jiraCtx)
+func NewGenerator(client jira.Client, usePR bool, fromRef, toRef, repoURL string) *Generator {
 	g := &Generator{
-		JiraConfig: jiraCtx,
-		fromRef:    fromRef,
-		toRef:      toRef,
-		repoURL:    repoURL,
-		client:     client,
+		fromRef: fromRef,
+		toRef:   toRef,
+		repoURL: repoURL,
+		client:  client,
+		usePR:   usePR,
 	}
 
 	return g
 }
 
 func (c *Generator) Generate(ctx context.Context) *Changelog {
-	populator, err := messages.NewPullRequestPopulator(c.fromRef, c.toRef, c.repoURL)
+	populator, err := messages.NewCommitOrPRPopualtor(c.usePR, c.fromRef, c.toRef, c.repoURL)
 	panicIfErr(err)
 
 	commits, err := populator.Populate(ctx)
diff --git a/pkg/jira_changelog/generator_test.go b/pkg/jira_changelog/generator_test.go
index c81922e..6225cb0 100644
--- a/pkg/jira_changelog/generator_test.go
+++ b/pkg/jira_changelog/generator_test.go
@@ -35,7 +35,7 @@ func TestFetchJiraIssuesEvent(t *testing.T) {
 	mockedClient.On("FetchIssue", "TEST-4546").Return(want[1], nil).Twice()
 	mockedClient.On("FetchIssue", "TEST-12345").Return(want[2], nil)
 
-	generator := NewGenerator(jira.NewContext(nil), "fromRef", "toRef", "http://example-repo.com")
+	generator := NewGenerator(jira.NewClient(jira.NewContext(nil)), false, "fromRef", "toRef", "http://example-repo.com")
 	generator.client = mockedClient
 
 	changeMessages := lo.Map(commits, func(commit messages.Commit, i int) messages.Message { return commit })
diff --git a/pkg/jira_changelog/messages/git_commits_populator.go b/pkg/jira_changelog/messages/git_commits_populator.go
index fef815a..ffe1083 100644
--- a/pkg/jira_changelog/messages/git_commits_populator.go
+++ b/pkg/jira_changelog/messages/git_commits_populator.go
@@ -27,12 +27,12 @@ type commitPopulator struct {
 	toRef   string
 }
 
-func NewCommitPopulator(fromRef, toRef string) Populator {
+func NewCommitPopulator(fromRef, toRef string) (Populator, error) {
 	cpw := &commitPopulator{
 		fromRef: fromRef,
 		toRef:   toRef,
 	}
-	return cpw
+	return cpw, nil
 }
 
 func (cpw *commitPopulator) Populate(ctx context.Context) ([]Message, error) {
diff --git a/pkg/jira_changelog/messages/populator.go b/pkg/jira_changelog/messages/populator.go
index 33b96f2..7718e2f 100644
--- a/pkg/jira_changelog/messages/populator.go
+++ b/pkg/jira_changelog/messages/populator.go
@@ -1,6 +1,10 @@
 package messages
 
-import "context"
+import (
+	"context"
+
+	"golang.org/x/exp/slog"
+)
 
 type Message interface {
 	Message() string
@@ -9,3 +13,13 @@ type Message interface {
 type Populator interface {
 	Populate(ctx context.Context) ([]Message, error)
 }
+
+func NewCommitOrPRPopualtor(usePR bool, fromRef, toRef, repoURL string) (Populator, error) {
+	if usePR {
+		slog.Debug("using github PR titles to generate changelog")
+		return NewPullRequestPopulator(fromRef, toRef, repoURL)
+	} else {
+		slog.Debug("using commit messages to generate changelog")
+		return NewCommitPopulator(fromRef, toRef)
+	}
+}