// Copyright (c) 2026 Storm Dragon
// Authors: Storm Dragon, Angus Kola
// SPDX-License-Identifier: GPL-3.0-or-later

package clipboard

import (
	"encoding/json"
	"io"
	"net/url"
	"os"
	"path"
	"path/filepath"
	"strconv"
	"strings"
	"syscall"
)

// Snapshot contains only the clipboard facts needed for Cthulhu's announcement.
type Snapshot struct {
	Text    string   `json:"text"`
	HasText bool     `json:"hasText"`
	Image   bool     `json:"image"`
	URIs    []string `json:"uris"`
}

// WriteMessage is called only by the short lived clipboard helper process.
// URI filesystem checks stay here so the parent can enforce a read deadline.
func WriteMessage(output io.Writer) error {
	snapshot, err := read_native()
	if err != nil {
		return err
	}
	return json.NewEncoder(output).Encode(struct {
		Message string `json:"message"`
	}{Message: Format(snapshot)})
}

func Format(snapshot Snapshot) string {
	if snapshot.Image {
		return "The clipboard contains a image"
	}
	if len(snapshot.URIs) != 0 {
		return format_uris(snapshot.URIs)
	}
	if snapshot.HasText {
		return "Text in clipboard " + snapshot.Text
	}
	return "The clipboard is empty"
}

func format_uris(uris []string) string {
	objects := make([]string, 0, len(uris))
	for _, raw := range uris {
		if raw == "" {
			continue
		}
		parsed, err := url.Parse(raw)
		if err != nil {
			objects = append(objects, raw)
			continue
		}
		name := path.Base(parsed.Path)
		if name == "." || name == "/" {
			name = raw
		}
		parts := []string{name}
		if parsed.Scheme == "file" && (parsed.Host == "" || parsed.Host == "localhost") {
			localPath := parsed.Path
			link := false
			if info, err := os.Lstat(localPath); err == nil && info.Mode()&os.ModeSymlink != 0 {
				link = true
			}
			if info, err := os.Stat(localPath); err == nil {
				if info.IsDir() {
					parts = append(parts, "Folder")
				} else if info.Mode().IsRegular() {
					parts = append(parts, "File")
				}
				if !link && is_mount(localPath, info) {
					parts = append(parts, "Disk")
				}
			}
			if link {
				parts = append(parts, "Link")
			}
		}
		objects = append(objects, strings.Join(parts, " "))
	}
	if len(objects) == 0 {
		return "The clipboard is empty"
	}
	label := " Object in clipboard "
	if len(objects) > 1 {
		label = " Objects in clipboard "
	}
	return strconv.Itoa(len(objects)) + label + strings.Join(objects, " ")
}

func is_mount(localPath string, info os.FileInfo) bool {
	parentPath := filepath.Dir(filepath.Clean(localPath))
	parent, err := os.Stat(parentPath)
	if err != nil {
		return false
	}
	currentStat, currentOK := info.Sys().(*syscall.Stat_t)
	parentStat, parentOK := parent.Sys().(*syscall.Stat_t)
	return currentOK && parentOK && (currentStat.Dev != parentStat.Dev || currentStat.Ino == parentStat.Ino)
}