Use Survey For Interactions With User (#186)

fixes

Use Survey For Interactions With User

Add Vendor "github.com/AlecAivazis/survey/v2"

Co-authored-by: Norwin Roosen <git@nroo.de>
Co-authored-by: 6543 <6543@obermui.de>
Reviewed-on: https://gitea.com/gitea/tea/pulls/186
Reviewed-by: techknowlogick <techknowlogick@gitea.io>
Reviewed-by: Norwin <noerw@noreply.gitea.io>

vendor/github.com/AlecAivazis/survey/v2/renderer.go

@@ -0,0 +1,157 @@
+package survey
+
+import (
+	"bytes"
+	"fmt"
+	"unicode/utf8"
+
+	"github.com/AlecAivazis/survey/v2/core"
+	"github.com/AlecAivazis/survey/v2/terminal"
+	goterm "golang.org/x/crypto/ssh/terminal"
+)
+
+type Renderer struct {
+	stdio          terminal.Stdio
+	renderedErrors bytes.Buffer
+	renderedText   bytes.Buffer
+}
+
+type ErrorTemplateData struct {
+	Error error
+	Icon  Icon
+}
+
+var ErrorTemplate = `{{color .Icon.Format }}{{ .Icon.Text }} Sorry, your reply was invalid: {{ .Error.Error }}{{color "reset"}}
+`
+
+func (r *Renderer) WithStdio(stdio terminal.Stdio) {
+	r.stdio = stdio
+}
+
+func (r *Renderer) Stdio() terminal.Stdio {
+	return r.stdio
+}
+
+func (r *Renderer) NewRuneReader() *terminal.RuneReader {
+	return terminal.NewRuneReader(r.stdio)
+}
+
+func (r *Renderer) NewCursor() *terminal.Cursor {
+	return &terminal.Cursor{
+		In:  r.stdio.In,
+		Out: r.stdio.Out,
+	}
+}
+
+func (r *Renderer) Error(config *PromptConfig, invalid error) error {
+	// cleanup the currently rendered errors
+	r.resetPrompt(r.countLines(r.renderedErrors))
+	r.renderedErrors.Reset()
+
+	// cleanup the rest of the prompt
+	r.resetPrompt(r.countLines(r.renderedText))
+	r.renderedText.Reset()
+
+	userOut, layoutOut, err := core.RunTemplate(ErrorTemplate, &ErrorTemplateData{
+		Error: invalid,
+		Icon:  config.Icons.Error,
+	})
+	if err != nil {
+		return err
+	}
+
+	// send the message to the user
+	fmt.Fprint(terminal.NewAnsiStdout(r.stdio.Out), userOut)
+
+	// add the printed text to the rendered error buffer so we can cleanup later
+	r.appendRenderedError(layoutOut)
+
+	return nil
+}
+
+func (r *Renderer) Render(tmpl string, data interface{}) error {
+	// cleanup the currently rendered text
+	lineCount := r.countLines(r.renderedText)
+	r.resetPrompt(lineCount)
+	r.renderedText.Reset()
+
+	// render the template summarizing the current state
+	userOut, layoutOut, err := core.RunTemplate(tmpl, data)
+	if err != nil {
+		return err
+	}
+
+	// print the summary
+	fmt.Fprint(terminal.NewAnsiStdout(r.stdio.Out), userOut)
+
+	// add the printed text to the rendered text buffer so we can cleanup later
+	r.AppendRenderedText(layoutOut)
+
+	// nothing went wrong
+	return nil
+}
+
+// appendRenderedError appends text to the renderer's error buffer
+// which is used to track what has been printed. It is not exported
+// as errors should only be displayed via Error(config, error).
+func (r *Renderer) appendRenderedError(text string) {
+	r.renderedErrors.WriteString(text)
+}
+
+// AppendRenderedText appends text to the renderer's text buffer
+// which is used to track of what has been printed. The buffer is used
+// to calculate how many lines to erase before updating the prompt.
+func (r *Renderer) AppendRenderedText(text string) {
+	r.renderedText.WriteString(text)
+}
+
+func (r *Renderer) resetPrompt(lines int) {
+	// clean out current line in case tmpl didnt end in newline
+	cursor := r.NewCursor()
+	cursor.HorizontalAbsolute(0)
+	terminal.EraseLine(r.stdio.Out, terminal.ERASE_LINE_ALL)
+	// clean up what we left behind last time
+	for i := 0; i < lines; i++ {
+		cursor.PreviousLine(1)
+		terminal.EraseLine(r.stdio.Out, terminal.ERASE_LINE_ALL)
+	}
+}
+
+func (r *Renderer) termWidth() (int, error) {
+	fd := int(r.stdio.Out.Fd())
+	termWidth, _, err := goterm.GetSize(fd)
+	return termWidth, err
+}
+
+// countLines will return the count of `\n` with the addition of any
+// lines that have wrapped due to narrow terminal width
+func (r *Renderer) countLines(buf bytes.Buffer) int {
+	w, err := r.termWidth()
+	if err != nil || w == 0 {
+		// if we got an error due to terminal.GetSize not being supported
+		// on current platform then just assume a very wide terminal
+		w = 10000
+	}
+
+	bufBytes := buf.Bytes()
+
+	count := 0
+	curr := 0
+	delim := -1
+	for curr < len(bufBytes) {
+		// read until the next newline or the end of the string
+		relDelim := bytes.IndexRune(bufBytes[curr:], '\n')
+		if relDelim != -1 {
+			count += 1 // new line found, add it to the count
+			delim = curr + relDelim
+		} else {
+			delim = len(bufBytes) // no new line found, read rest of text
+		}
+
+		// account for word wrapping
+		count += int(utf8.RuneCount(bufBytes[curr:delim]) / w)
+		curr = delim + 1
+	}
+
+	return count
+}