// Fenrir console screen reader.
// Copyright (c) 2026 Storm Dragon
// SPDX-License-Identifier: GPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the Free
// Software Foundation, either version 3 of the License, or (at your option)
// any later version.
//
// This program is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
// more details.
//
// You should have received a copy of the GNU General Public License along with
// this program. If not, see <https://www.gnu.org/licenses/gpl-3.0.html>.

package interaction

import (
	"git.stormux.org/storm/fenrir/internal/i18n"
	"strings"
	"unicode"
)

func (s *Session) edit(control *Control, key Key) Result {
	runes := []rune(control.Text)
	if key.Ctrl {
		if strings.EqualFold(key.Text, "a") {
			s.selectAll = true
			return Result{Speech: i18n.T("selected") + " " + control.Text}
		}
		return Result{}
	}
	switch key.Name {
	case "enter":
		return Result{Action: control.Action}
	case "left":
		s.cursor = max(0, s.cursor-1)
		s.selectAll = false
	case "right":
		s.cursor = min(len(runes), s.cursor+1)
		s.selectAll = false
	case "home":
		s.cursor = 0
		s.selectAll = false
	case "end":
		s.cursor = len(runes)
		s.selectAll = false
	case "backspace", "delete":
		if s.selectAll {
			runes = nil
			s.cursor = 0
		} else if key.Name == "backspace" && s.cursor > 0 {
			runes = append(runes[:s.cursor-1], runes[s.cursor:]...)
			s.cursor--
		} else if key.Name == "delete" && s.cursor < len(runes) {
			runes = append(runes[:s.cursor], runes[s.cursor+1:]...)
		}
		s.selectAll = false
	default:
		text := []rune(key.Text)
		if len(text) == 0 {
			return Result{}
		}
		for _, char := range text {
			if !unicode.IsPrint(char) {
				return Result{}
			}
		}
		length := len(runes)
		if s.selectAll {
			length = 0
		}
		if length+len(text) > 4096 {
			return Result{}
		}
		if s.selectAll {
			runes = nil
			s.cursor = 0
		}
		runes = append(runes[:s.cursor], append(text, runes[s.cursor:]...)...)
		s.cursor += len(text)
		s.selectAll = false
	}
	control.Text = string(runes)
	if (key.Name == "left" || key.Name == "right" || key.Name == "home" || key.Name == "end") && s.cursor < len(runes) {
		return Result{Speech: string(runes[s.cursor])}
	}
	return Result{Speech: s.Describe()}
}