1 files changed, 348 insertions, 0 deletions
diff --git a/commands/input/input.go b/commands/input/input.go
new file mode 100644
index 00000000..e9c1be1b
--- /dev/null
+++ b/commands/input/input.go
@@ -0,0 +1,348 @@
+// Inspired by the git-appraise project
+
+// Package input contains helpers to use a text editor as an input for
+// various field of a bug
+package input
+
+import (
+	"bufio"
+	"bytes"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
+
+	"github.com/go-git/go-billy/v5/util"
+	"github.com/pkg/errors"
+
+	"github.com/MichaelMure/git-bug/repository"
+)
+
+const messageFilename = "BUG_MESSAGE_EDITMSG"
+
+// ErrEmptyMessage is returned when the required message has not been entered
+var ErrEmptyMessage = errors.New("empty message")
+
+// ErrEmptyMessage is returned when the required title has not been entered
+var ErrEmptyTitle = errors.New("empty title")
+
+const bugTitleCommentTemplate = `%s%s
+
+# Please enter the title and comment message. The first non-empty line will be
+# used as the title. Lines starting with '#' will be ignored.
+# An empty title aborts the operation.
+`
+
+// BugCreateEditorInput will open the default editor in the terminal with a
+// template for the user to fill. The file is then processed to extract title
+// and message.
+func BugCreateEditorInput(repo repository.RepoCommonStorage, preTitle string, preMessage string) (string, string, error) {
+	if preMessage != "" {
+		preMessage = "\n\n" + preMessage
+	}
+
+	template := fmt.Sprintf(bugTitleCommentTemplate, preTitle, preMessage)
+
+	raw, err := launchEditorWithTemplate(repo, messageFilename, template)
+
+	if err != nil {
+		return "", "", err
+	}
+
+	return processCreate(raw)
+}
+
+// BugCreateFileInput read from either from a file or from the standard input
+// and extract a title and a message
+func BugCreateFileInput(fileName string) (string, string, error) {
+	raw, err := fromFile(fileName)
+	if err != nil {
+		return "", "", err
+	}
+
+	return processCreate(raw)
+}
+
+func processCreate(raw string) (string, string, error) {
+	lines := strings.Split(raw, "\n")
+
+	var title string
+	var buffer bytes.Buffer
+	for _, line := range lines {
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+
+		if title == "" {
+			trimmed := strings.TrimSpace(line)
+			if trimmed != "" {
+				title = trimmed
+			}
+			continue
+		}
+
+		buffer.WriteString(line)
+		buffer.WriteString("\n")
+	}
+
+	if title == "" {
+		return "", "", ErrEmptyTitle
+	}
+
+	message := strings.TrimSpace(buffer.String())
+
+	return title, message, nil
+}
+
+const bugCommentTemplate = `%s
+
+# Please enter the comment message. Lines starting with '#' will be ignored,
+# and an empty message aborts the operation.
+`
+
+// BugCommentEditorInput will open the default editor in the terminal with a
+// template for the user to fill. The file is then processed to extract a comment.
+func BugCommentEditorInput(repo repository.RepoCommonStorage, preMessage string) (string, error) {
+	template := fmt.Sprintf(bugCommentTemplate, preMessage)
+
+	raw, err := launchEditorWithTemplate(repo, messageFilename, template)
+	if err != nil {
+		return "", err
+	}
+
+	return processComment(raw)
+}
+
+// BugCommentFileInput read from either from a file or from the standard input
+// and extract a message
+func BugCommentFileInput(fileName string) (string, error) {
+	raw, err := fromFile(fileName)
+	if err != nil {
+		return "", err
+	}
+
+	return processComment(raw)
+}
+
+func processComment(raw string) (string, error) {
+	lines := strings.Split(raw, "\n")
+
+	var buffer bytes.Buffer
+	for _, line := range lines {
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+		buffer.WriteString(line)
+		buffer.WriteString("\n")
+	}
+
+	message := strings.TrimSpace(buffer.String())
+
+	if message == "" {
+		return "", ErrEmptyMessage
+	}
+
+	return message, nil
+}
+
+const bugTitleTemplate = `%s
+
+# Please enter the new title. Only one line will used.
+# Lines starting with '#' will be ignored, and an empty title aborts the operation.
+`
+
+// BugTitleEditorInput will open the default editor in the terminal with a
+// template for the user to fill. The file is then processed to extract a title.
+func BugTitleEditorInput(repo repository.RepoCommonStorage, preTitle string) (string, error) {
+	template := fmt.Sprintf(bugTitleTemplate, preTitle)
+
+	raw, err := launchEditorWithTemplate(repo, messageFilename, template)
+	if err != nil {
+		return "", err
+	}
+
+	lines := strings.Split(raw, "\n")
+
+	var title string
+	for _, line := range lines {
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+		trimmed := strings.TrimSpace(line)
+		if trimmed == "" {
+			continue
+		}
+		title = trimmed
+		break
+	}
+
+	if title == "" {
+		return "", ErrEmptyTitle
+	}
+
+	return title, nil
+}
+
+const queryTemplate = `%s
+
+# Please edit the bug query.
+# Lines starting with '#' will be ignored, and an empty query aborts the operation.
+#
+# Example: status:open author:"rené descartes" sort:edit
+#
+# Valid filters are:
+#
+# - status:open, status:closed
+# - author:<query>
+# - title:<title>
+# - label:<label>
+# - no:label
+#
+# Sorting
+#
+# - sort:id, sort:id-desc, sort:id-asc
+# - sort:creation, sort:creation-desc, sort:creation-asc
+# - sort:edit, sort:edit-desc, sort:edit-asc
+#
+# Notes
+# 
+# - queries are case insensitive.
+# - you can combine as many qualifiers as you want.
+# - you can use double quotes for multi-word search terms (ex: author:"René Descartes")
+`
+
+// QueryEditorInput will open the default editor in the terminal with a
+// template for the user to fill. The file is then processed to extract a query.
+func QueryEditorInput(repo repository.RepoCommonStorage, preQuery string) (string, error) {
+	template := fmt.Sprintf(queryTemplate, preQuery)
+
+	raw, err := launchEditorWithTemplate(repo, messageFilename, template)
+	if err != nil {
+		return "", err
+	}
+
+	lines := strings.Split(raw, "\n")
+
+	for _, line := range lines {
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+		trimmed := strings.TrimSpace(line)
+		if trimmed == "" {
+			continue
+		}
+		return trimmed, nil
+	}
+
+	return "", nil
+}
+
+// launchEditorWithTemplate will launch an editor as launchEditor do, but with a
+// provided template.
+func launchEditorWithTemplate(repo repository.RepoCommonStorage, fileName string, template string) (string, error) {
+	err := util.WriteFile(repo.LocalStorage(), fileName, []byte(template), 0644)
+	if err != nil {
+		return "", err
+	}
+
+	return launchEditor(repo, fileName)
+}
+
+// launchEditor launches the default editor configured for the given repo. This
+// method blocks until the editor command has returned.
+//
+// The specified filename should be a temporary file and provided as a relative path
+// from the repo (e.g. "FILENAME" will be converted to "[<reporoot>/].git/git-bug/FILENAME"). This file
+// will be deleted after the editor is closed and its contents have been read.
+//
+// This method returns the text that was read from the temporary file, or
+// an error if any step in the process failed.
+func launchEditor(repo repository.RepoCommonStorage, fileName string) (string, error) {
+	defer repo.LocalStorage().Remove(fileName)
+
+	editor, err := repo.GetCoreEditor()
+	if err != nil {
+		return "", fmt.Errorf("Unable to detect default git editor: %v\n", err)
+	}
+
+	repo.LocalStorage().Root()
+
+	// bypass the interface but that's ok: we need that because we are communicating
+	// the absolute path to an external program
+	path := filepath.Join(repo.LocalStorage().Root(), fileName)
+
+	cmd, err := startInlineCommand(editor, path)
+	if err != nil {
+		// Running the editor directly did not work. This might mean that
+		// the editor string is not a path to an executable, but rather
+		// a shell command (e.g. "emacsclient --tty"). As such, we'll try
+		// to run the command through bash, and if that fails, try with sh
+		args := []string{"-c", fmt.Sprintf("%s %q", editor, path)}
+		cmd, err = startInlineCommand("bash", args...)
+		if err != nil {
+			cmd, err = startInlineCommand("sh", args...)
+		}
+	}
+	if err != nil {
+		return "", fmt.Errorf("Unable to start editor: %v\n", err)
+	}
+
+	if err := cmd.Wait(); err != nil {
+		return "", fmt.Errorf("Editing finished with error: %v\n", err)
+	}
+
+	output, err := ioutil.ReadFile(path)
+
+	if err != nil {
+		return "", fmt.Errorf("Error reading edited file: %v\n", err)
+	}
+
+	return string(output), err
+}
+
+// fromFile loads and returns the contents of a given file. If - is passed
+// through, much like git, it will read from stdin. This can be piped data,
+// unless there is a tty in which case the user will be prompted to enter a
+// message.
+func fromFile(fileName string) (string, error) {
+	if fileName == "-" {
+		stat, err := os.Stdin.Stat()
+		if err != nil {
+			return "", fmt.Errorf("Error reading from stdin: %v\n", err)
+		}
+		if (stat.Mode() & os.ModeCharDevice) == 0 {
+			// There is no tty. This will allow us to read piped data instead.
+			output, err := ioutil.ReadAll(os.Stdin)
+			if err != nil {
+				return "", fmt.Errorf("Error reading from stdin: %v\n", err)
+			}
+			return string(output), err
+		}
+
+		fmt.Printf("(reading comment from standard input)\n")
+		var output bytes.Buffer
+		s := bufio.NewScanner(os.Stdin)
+		for s.Scan() {
+			output.Write(s.Bytes())
+			output.WriteRune('\n')
+		}
+		return output.String(), nil
+	}
+
+	output, err := ioutil.ReadFile(fileName)
+	if err != nil {
+		return "", fmt.Errorf("Error reading file: %v\n", err)
+	}
+	return string(output), err
+}
+
+func startInlineCommand(command string, args ...string) (*exec.Cmd, error) {
+	cmd := exec.Command(command, args...)
+	cmd.Stdin = os.Stdin
+	cmd.Stdout = os.Stdout
+	cmd.Stderr = os.Stderr
+	err := cmd.Start()
+	return cmd, err
+}