import 'package:comunic/ui/screens/call_screen.dart';
import 'package:comunic/ui/widgets/tablet_mode/calls/calls_area.dart';
import 'package:flutter/material.dart';

/// Call window widget
///
/// @author Pierre HUBERT

const _WindowSize = Size(500, 200);

class CallWindowWidget extends StatefulWidget {
  final int convID;

  const CallWindowWidget({
    Key key,
    this.convID,
  })  : assert(convID != null),
        super(key: key);

  @override
  _CallWindowWidgetState createState() => _CallWindowWidgetState();
}

class _CallWindowWidgetState extends State<CallWindowWidget> {
  double _left, _top;

  @override
  void didChangeDependencies() {
    super.didChangeDependencies();

    // Initialize window coordinates
    _top = 10;
    _left = MediaQuery.of(context).size.width - 10 - _WindowSize.width;
  }

  @override
  Widget build(BuildContext context) {
    return Positioned(
      width: _WindowSize.width,
      height: _WindowSize.height,
      left: _left,
      top: _top,
      child: Draggable(
        child: Card(
          child: CallScreen(
            convID: widget.convID,
            floatingButtons: false,
          ),
        ),
        feedback: Container(
          width: _WindowSize.width,
          height: _WindowSize.height,
          color: Colors.red,
        ),
        onDragEnd: _moveEnd,
      ),
    );
  }

  /// Compute new window position
  void _moveEnd(DraggableDetails details) {
    // Determine the limits of containing stack
    RenderBox renderBox = context
        .findAncestorStateOfType<CallsAreaState>()
        .context
        .findRenderObject();
    final size = renderBox.size;
    final offset = renderBox.localToGlobal(Offset.zero);

    // Determine new window position
    _top = details.offset.dy - offset.dy;
    _left = details.offset.dx - offset.dx;

    // Force the window to appear completely on the screen
    if (_top + _WindowSize.height >= size.height)
      _top = size.height - _WindowSize.height;
    if (_left + _WindowSize.width >= size.width)
      _left = size.width - _WindowSize.width;

    if (_top < 0) _top = 0;
    if (_left < 0) _left = 0;

    setState(() {});
  }
}