package platform

import (
	"io"
	"strings"
	"sync"

	gioclipboard "gioui.org/io/clipboard"
	"gioui.org/layout"

	appclipboard "git.julianfamily.org/keepassgo/internal/clipboard"
)

type VaultSharer interface {
	ShareVault(path, title string) error
}

type clipboardCommandWriter struct {
	mu         sync.Mutex
	pending    []string
	invalidate func()
}

func NewClipboardWriter(goos string, invalidate func()) appclipboard.Writer {
	if strings.EqualFold(goos, "android") {
		return &clipboardCommandWriter{invalidate: invalidate}
	}
	return nil
}

func ProcessClipboardWrites(gtx layout.Context, writer appclipboard.Writer) {
	commandWriter, ok := writer.(*clipboardCommandWriter)
	if !ok {
		return
	}
	commandWriter.Process(gtx)
}

func (w *clipboardCommandWriter) WriteText(text string) error {
	w.mu.Lock()
	w.pending = append(w.pending, text)
	w.mu.Unlock()
	if w.invalidate != nil {
		w.invalidate()
	}
	return nil
}

func (w *clipboardCommandWriter) Process(gtx layout.Context) {
	for _, text := range w.drain() {
		gtx.Execute(gioclipboard.WriteCmd{
			Type: "application/text",
			Data: io.NopCloser(strings.NewReader(text)),
		})
	}
}

func (w *clipboardCommandWriter) drain() []string {
	w.mu.Lock()
	defer w.mu.Unlock()
	if len(w.pending) == 0 {
		return nil
	}
	pending := append([]string(nil), w.pending...)
	w.pending = nil
	return pending
}