Multiline comment and suggestion (#66)

This MR adds the ability to leave multi-line comments and suggested changes to an MR. The features are only supported for `diffview` because we plan to deprecate `delta` as a reviewer soon.

cmd/comment.go

@@ -1,8 +1,10 @@
 package main
 
 import (
+	"crypto/sha1"
 	"encoding/json"
 	"errors"
+	"fmt"
 	"io"
 	"net/http"
 
@@ -12,14 +14,29 @@ import (
 const mrVersionsUrl = "%s/api/v4/projects/%s/merge_requests/%d/versions"
 
 type PostCommentRequest struct {
-	Comment        string `json:"comment"`
-	FileName       string `json:"file_name"`
-	NewLine        int    `json:"new_line"`
-	OldLine        int    `json:"old_line"`
-	HeadCommitSHA  string `json:"head_commit_sha"`
-	BaseCommitSHA  string `json:"base_commit_sha"`
-	StartCommitSHA string `json:"start_commit_sha"`
-	Type           string `json:"type"`
+	Comment        string     `json:"comment"`
+	FileName       string     `json:"file_name"`
+	NewLine        *int       `json:"new_line,omitempty"`
+	OldLine        *int       `json:"old_line,omitempty"`
+	HeadCommitSHA  string     `json:"head_commit_sha"`
+	BaseCommitSHA  string     `json:"base_commit_sha"`
+	StartCommitSHA string     `json:"start_commit_sha"`
+	Type           string     `json:"type"`
+	LineRange      *LineRange `json:"line_range,omitempty"`
+}
+
+// LineRange represents the range of a note.
+type LineRange struct {
+	StartRange *LinePosition `json:"start"`
+	EndRange   *LinePosition `json:"end"`
+}
+
+// LinePosition represents a position in a line range.
+// unlike gitlab struct this does not contain LineCode with sha1 of filename
+type LinePosition struct {
+	Type    string `json:"type"`
+	OldLine int    `json:"old_line"`
+	NewLine int    `json:"new_line"`
 }
 
 type DeleteCommentRequest struct {
@@ -115,16 +132,42 @@ func PostComment(w http.ResponseWriter, r *http.Request) {
 	/* If we are leaving a comment on a line, leave position. Otherwise,
 	we are leaving a note (unlinked comment) */
 	if postCommentRequest.FileName != "" {
-		opt.Position = &gitlab.NotePosition{
-			PositionType: "text",
-			StartSHA:     postCommentRequest.StartCommitSHA,
-			HeadSHA:      postCommentRequest.HeadCommitSHA,
-			BaseSHA:      postCommentRequest.BaseCommitSHA,
-			NewPath:      postCommentRequest.FileName,
-			OldPath:      postCommentRequest.FileName,
+		opt.Position = &gitlab.PositionOptions{
+			PositionType: &postCommentRequest.Type,
+			StartSHA:     &postCommentRequest.StartCommitSHA,
+			HeadSHA:      &postCommentRequest.HeadCommitSHA,
+			BaseSHA:      &postCommentRequest.BaseCommitSHA,
+			NewPath:      &postCommentRequest.FileName,
+			OldPath:      &postCommentRequest.FileName,
 			NewLine:      postCommentRequest.NewLine,
 			OldLine:      postCommentRequest.OldLine,
 		}
+
+		if postCommentRequest.LineRange != nil {
+			var format = "%x_%d_%d"
+			var start_filename_sha1 = fmt.Sprintf(
+				format,
+				sha1.Sum([]byte(postCommentRequest.FileName)),
+				postCommentRequest.LineRange.StartRange.OldLine,
+				postCommentRequest.LineRange.StartRange.NewLine,
+			)
+			var end_filename_sha1 = fmt.Sprintf(
+				format,
+				sha1.Sum([]byte(postCommentRequest.FileName)),
+				postCommentRequest.LineRange.EndRange.OldLine,
+				postCommentRequest.LineRange.EndRange.NewLine,
+			)
+			opt.Position.LineRange = &gitlab.LineRangeOptions{
+				Start: &gitlab.LinePositionOptions{
+					Type:     &postCommentRequest.LineRange.StartRange.Type,
+					LineCode: &start_filename_sha1,
+				},
+				End: &gitlab.LinePositionOptions{
+					Type:     &postCommentRequest.LineRange.EndRange.Type,
+					LineCode: &end_filename_sha1,
+				},
+			}
+		}
 	}
 
 	discussion, _, err := c.git.Discussions.CreateMergeRequestDiscussion(c.projectId, c.mergeId, &opt)