import 'dart:ui';

import 'package:flutter/material.dart';
import 'package:auto_size_text/auto_size_text.dart';

import 'package:anyway/structs/trip.dart';
import 'package:anyway/pages/current_trip.dart';

class CurrentTripLoadingIndicator extends StatefulWidget {
  final Trip trip;
  const CurrentTripLoadingIndicator({
    super.key,
    required this.trip,
  });

  @override
  State<CurrentTripLoadingIndicator> createState() => _CurrentTripLoadingIndicatorState();
}


Widget bottomLoadingIndicator = Container(
  height: 20.0, // Increase the height to take up more vertical space

  child: ImageFiltered(
    imageFilter: ImageFilter.blur(sigmaX: 5.0, sigmaY: 5.0), // Apply blur effect
    child: Padding(padding: EdgeInsets.all(10), child: CircularProgressIndicator(),)
    ),
);


Widget loadingText(Trip trip) => FutureBuilder(
  future: trip.cityName,
  builder: (BuildContext context, AsyncSnapshot<String> snapshot) {
    Widget greeter;

    if (snapshot.hasData) {
      greeter = AnimatedGradientText(
        text: 'Generating your trip to ${snapshot.data}...',
        style: greeterStyle,
      );
    } else if (snapshot.hasError) {
      // the exact error is shown in the central part of the trip overview. No need to show it here
      greeter = AnimatedGradientText(
        text: 'Error while loading trip.',
        style: greeterStyle,
      );
    } else {
      greeter = AnimatedGradientText(
        text: 'Generating your trip...',
        style: greeterStyle,
      );
    }
    return greeter;
  }
);

class AnimatedGradientText extends StatefulWidget {
  final String text;
  final TextStyle style;

  const AnimatedGradientText({
    Key? key,
    required this.text,
    required this.style,
  }) : super(key: key);

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

class _AnimatedGradientTextState extends State<AnimatedGradientText> with SingleTickerProviderStateMixin {
  late AnimationController _controller;

  @override
  void initState() {
    super.initState();
    _controller = AnimationController(
      duration: const Duration(seconds: 1),
      vsync: this,
    )..repeat();
  }

  @override
  void dispose() {
    _controller.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return AnimatedBuilder(
      animation: _controller,
      builder: (context, child) {
        return ShaderMask(
          shaderCallback: (bounds) {
            return LinearGradient(
              colors: [Colors.blue, Colors.red, Colors.blue],
              stops: [
                _controller.value - 1.0,
                _controller.value,
                _controller.value + 1.0,
              ],
              tileMode: TileMode.mirror,
            ).createShader(bounds);
          },
          child: Text(
            widget.text,
            style: widget.style,
          ),
        );
      },
    );
  }
}




class _CurrentTripLoadingIndicatorState extends State<CurrentTripLoadingIndicator> {
  @override
  Widget build(BuildContext context) => Stack(
    fit: StackFit.expand,
    children: [
      Center(child: loadingText(widget.trip)),
      Align(
        alignment: Alignment.bottomCenter,
        child: bottomLoadingIndicator,
      )
    ],
  );

}