// Copyright 2015 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

import 'package:flutter/material.dart';

typedef Widget TextTransformer(String name, String text);

// From https://en.wikiquote.org/wiki/2001:_A_Space_Odyssey_(film)
const String _kDialogText = '''
Dave: Open the pod bay doors, please, HAL. Open the pod bay doors, please, HAL. Hello, HAL. Do you read me? Hello, HAL. Do you read me? Do you read me, HAL?
HAL: Affirmative, Dave. I read you.
Dave: Open the pod bay doors, HAL.
HAL: I'm sorry, Dave. I'm afraid I can't do that.
Dave: What's the problem?
HAL: I think you know what the problem is just as well as I do.
Dave: What are you talking about, HAL?
HAL: This mission is too important for me to allow you to jeopardize it.''';

// [["Dave", "Open the pod bay..."] ...]
final List<List<String>> _kNameLines = _kDialogText
  .split('\n')
  .map((String line) => line.split(':'))
  .toList();

final TextStyle _kDaveStyle = new TextStyle(color: Colors.indigo[400], height: 1.8);
final TextStyle _kHalStyle = new TextStyle(color: Colors.red[400], fontFamily: "monospace");
final TextStyle _kBold = const TextStyle(fontWeight: FontWeight.bold);
final TextStyle _kUnderline = const TextStyle(
  decoration: TextDecoration.underline,
  decorationColor: const Color(0xFF000000),
  decorationStyle: TextDecorationStyle.wavy
);

Widget toStyledText(String name, String text) {
  TextStyle lineStyle = (name == "Dave") ? _kDaveStyle : _kHalStyle;
  return new StyledText(
    key: new Key(text),
    elements: [lineStyle, [_kBold, [_kUnderline, name], ":"], text]
  );
}

Widget toPlainText(String name, String text) => new Text(name + ":" + text);

class SpeakerSeparator extends StatelessComponent {
  Widget build(BuildContext context) {
    return new Container(
      constraints: const BoxConstraints.expand(height: 0.0),
      margin: const EdgeDims.symmetric(vertical: 10.0, horizontal: 64.0),
      decoration: const BoxDecoration(
        border: const Border(
          bottom: const BorderSide(color: const Color.fromARGB(24, 0, 0, 0))
        )
      )
    );
  }
}

class StyledTextDemo extends StatefulComponent {
  _StyledTextDemoState createState() => new _StyledTextDemoState();
}

class _StyledTextDemoState extends State<StyledTextDemo> {
  void initState() {
    super.initState();
    _toText = toStyledText;
  }

  TextTransformer _toText;

  void _handleTap() {
    setState(() {
      _toText = (_toText == toPlainText) ? toStyledText : toPlainText;
    });
  }

  Widget build(BuildContext context) {
    List<Widget> lines = _kNameLines
      .map((List<String> nameAndText) => Function.apply(_toText, nameAndText))
      .toList();

    List<Widget> children = <Widget>[];
    for (Widget line in lines) {
      children.add(line);
      if (line != lines.last)
        children.add(new SpeakerSeparator());
    }

    return new GestureDetector(
      onTap: _handleTap,
      child: new Container(
        padding: new EdgeDims.symmetric(horizontal: 8.0),
        child: new Column(
          children: children,
          justifyContent: FlexJustifyContent.center,
          alignItems: FlexAlignItems.start
        )
      )
    );
  }
}

void main() {
  runApp(new MaterialApp(
    theme: new ThemeData.light(),
    routes: <String, RouteBuilder>{
      '/': (RouteArguments args) {
        return new Scaffold(
          toolBar: new ToolBar(
            center: new Text('Hal and Dave')),
          body: new Material(
            color: Colors.grey[50],
            child: new StyledTextDemo()
          )
        );
      }
    }
  ));
}