Start work on porting hints kitten to Go

tools/cmd/hints/main.go

@@ -0,0 +1,152 @@
+// License: GPLv3 Copyright: 2023, Kovid Goyal, <kovid at kovidgoyal.net>
+
+package hints
+
+import (
+	"fmt"
+	"io"
+	"os"
+	"strconv"
+	"strings"
+
+	"kitty/tools/cli"
+	"kitty/tools/tty"
+	"kitty/tools/tui"
+	"kitty/tools/tui/loop"
+	"kitty/tools/utils"
+	"kitty/tools/wcswidth"
+)
+
+var _ = fmt.Print
+
+func convert_text(text string, cols int) string {
+	lines := make([]string, 0, 64)
+	empty_line := strings.Repeat("\x00", cols) + "\n"
+	s1 := utils.NewLineScanner(text)
+	for s1.Scan() {
+		full_line := s1.Text()
+		if full_line == "" {
+			continue
+		}
+		if strings.TrimRight(full_line, "\r") == "" {
+			for i := 0; i < len(full_line); i++ {
+				lines = append(lines, empty_line)
+			}
+			continue
+		}
+		appended := false
+		s2 := utils.NewSeparatorScanner(full_line, "\r")
+		for s2.Scan() {
+			line := s2.Text()
+			if line != "" {
+				line_sz := wcswidth.Stringwidth(line)
+				extra := cols - line_sz
+				if extra > 0 {
+					line += strings.Repeat("\x00", extra)
+				}
+				lines = append(lines, line)
+				lines = append(lines, "\r")
+				appended = true
+			}
+		}
+		if appended {
+			lines[len(lines)-1] = "\n"
+		}
+	}
+	ans := strings.Join(lines, "")
+	return strings.TrimRight(ans, "\r\n")
+}
+
+func parse_input(text string) string {
+	cols, err := strconv.Atoi(os.Getenv("OVERLAID_WINDOW_COLS"))
+	if err == nil {
+		return convert_text(text, cols)
+	}
+	term, err := tty.OpenControllingTerm()
+	if err == nil {
+		sz, err := term.GetSize()
+		term.Close()
+		if err == nil {
+			return convert_text(text, int(sz.Col))
+		}
+	}
+	return convert_text(text, 80)
+}
+
+type Result struct {
+	Match                []string            `json:"match"`
+	Programs             []string            `json:"programs"`
+	Multiple_joiner      string              `json:"multiple_joiner"`
+	Customize_processing string              `json:"customize_processing"`
+	Type                 string              `json:"type"`
+	Groupdicts           []map[string]string `json:"groupdicts"`
+	Extra_cli_args       []string            `json:"extra_cli_args"`
+	Linenum_action       string              `json:"linenum_action"`
+	Cwd                  string              `json:"cwd"`
+}
+
+func main(_ *cli.Command, o *Options, args []string) (rc int, err error) {
+	output := tui.KittenOutputSerializer()
+	if tty.IsTerminal(os.Stdin.Fd()) {
+		tui.ReportError(fmt.Errorf("You must pass the text to be hinted on STDIN"))
+		return 1, nil
+	}
+	stdin, err := io.ReadAll(os.Stdin)
+	if err != nil {
+		tui.ReportError(fmt.Errorf("Failed to read from STDIN with error: %w", err))
+		return 1, nil
+	}
+	if len(args) > 0 && o.CustomizeProcessing == "" && o.Type != "linenum" {
+		tui.ReportError(fmt.Errorf("Extra command line arguments present: %s", strings.Join(args, " ")))
+		return 1, nil
+	}
+	text := parse_input(utils.UnsafeBytesToString(stdin))
+	all_marks, index_map, err := find_marks(text, o)
+	if err != nil {
+		tui.ReportError(err)
+		return 1, nil
+	}
+
+	result := Result{
+		Programs: o.Program, Multiple_joiner: o.MultipleJoiner, Customize_processing: o.CustomizeProcessing, Type: o.Type,
+		Extra_cli_args: args, Linenum_action: o.LinenumAction,
+	}
+	result.Cwd, _ = os.Getwd()
+	alphabet := o.Alphabet
+	if alphabet == "" {
+		alphabet = DEFAULT_HINT_ALPHABET
+	}
+	ignore_mark_indices := utils.NewSet[int](8)
+	_, _, _ = all_marks, index_map, ignore_mark_indices
+	window_title := o.WindowTitle
+	if window_title == "" {
+		switch o.Type {
+		case "url":
+			window_title = "Choose URL"
+		default:
+			window_title = "Choose text"
+		}
+	}
+	lp, err := loop.New(loop.NoAlternateScreen) // no alternate screen reduces flicker on exit
+	if err != nil {
+		return
+	}
+	lp.OnInitialize = func() (string, error) {
+		lp.SendOverlayReady()
+		lp.SetCursorVisible(false)
+		lp.SetWindowTitle(window_title)
+		lp.AllowLineWrapping(false)
+		return "", nil
+	}
+	lp.OnFinalize = func() string {
+		lp.SetCursorVisible(true)
+		return ""
+	}
+
+	output(result)
+	return
+}
+
+func EntryPoint(parent *cli.Command) {
+	create_cmd(parent, main)
+}