import 'dart:js_interop';
import 'package:web/web.dart' as web;
import 'package:flutter/material.dart';
import 'api_service.dart';
import 'structs.dart';
import 'package:html2md/html2md.dart' as html2md;
import 'package:markdown_widget/markdown_widget.dart';
import 'package:markdown/markdown.dart' as md;

class CollapsableEmails extends StatefulWidget {
  final List<String> thread; // email id's in the form xyz@gmail.com
  final List<String> threadHTML;
  final String threadIDs;

  CollapsableEmails(
      {required this.thread,
      required this.threadHTML,
      required this.threadIDs});

  @override
  State<CollapsableEmails> createState() => _CollapsableEmailsState();
}

class _CollapsableEmailsState extends State<CollapsableEmails> {
  List<String> emailsHTML = []; //html of the emails in the thread
  // build attachments with the forldar name and id
  Set<int> _expandedEmails = {}; //open emails
  List viewtypeIDs = []; //IDs of the viewtypes, order matters
  List heightOfViewTypes = []; //the height of each viewtype
  List<SerializableMessage> emailsInThread = [];
  bool _isLoaded = false;
  static bool _isListenerRegistered = false;
  static bool left = true;
  static bool right = true;
  web.EventListener? _listener;
  List<String> hirarchy = ["h1", "h2", "h3", "h4", "h5", "h6", "p"];
  Map<String, int> hirarchyDict = {
    "h1": 1,
    "h2": 2,
    "h3": 3,
    "h4": 4,
    "h5": 6,
    "h6": 7,
    "p": 8,
    "ul": 8,
    "li": 8,
  };

  List<String> tagsCollected = [];
  String markdown = '';
  List<List<String>> sentinel = [];
  int level = 0;
  AugmentTree zoomTreeRoot = AugmentTree();
  late AugmentTree currentZoomNode;
  bool zoomOut = false;
  bool zoomIn = true;

  @override
  void initState() {
    super.initState();
    _markdownConverter();
    // _registerViewFactory(widget.threadHTML);
    _serializableData(widget.threadIDs); // this
    _markdown2Tree(markdown);
    _keyListener();
    _buildForZooms();
  }

  @override
  void dispose() {
    if (_listener != null) {
      web.window.document.removeEventListener('keydown', _listener!);
      _listener = null;
      _isListenerRegistered = false;
    }
    super.dispose();
  }

  void _markdownConverter() async {
    markdown = html2md.convert(widget.threadHTML[0]);
  }

  void _add2Tree(AugmentTree tree, md.Element node2add) {
    // adds node to its corresponding place
    AugmentTree newNode = AugmentTree();
    newNode.setData(node2add.textContent);
    newNode.ogTag = node2add.tag;
    // cases,
    //1. a node that comes is lower than the root.children last, if so it goes beneath it
    if (tree.children.isEmpty) {
      // new level to be created when totally empty
      print('is empty');
      tree.children.add(newNode);
      newNode.parent = tree;
    } else if (tree.children.isNotEmpty &&
        tree.children.last.ogTag.isNotEmpty) {
      if ((hirarchyDict[node2add.tag] ??
              -1) < // e.g. new node is h1 and old is h2, heapify
          (hirarchyDict[tree.children.last.ogTag] ?? -1)) {
        //have to figure out the borthers
        //assuming it all goes right
        if ((hirarchyDict[node2add.tag] ?? -1) == -1 ||
            (hirarchyDict[tree.children.last.ogTag] ?? -1) == -1) {
          print(
              'failed and got -1 at _add2Tree \n ${hirarchyDict[node2add.tag] ?? -1} < ${hirarchyDict[tree.children.last.ogTag] ?? -1}');
          return;
        } else if (tree.children.last.parent == null) {
          // becomes the new top level
          for (AugmentTree brother in tree.children) {
            brother.parent = newNode;
          }
          tree.children = [newNode];
        } else {
          newNode.parent = tree;
          tree.children.add(newNode);
        }
      } else if ((hirarchyDict[node2add.tag] ??
              -1) > // go down e.g. new node is h3 and old is h2 or something
          (hirarchyDict[tree.children.last.ogTag] ?? -1)) {
        if ((hirarchyDict[node2add.tag] ?? -1) == -1 ||
            (hirarchyDict[tree.children.last.ogTag] ?? -1) == -1) {
          print(
              'failed and got -1 at _add2Tree \n ${hirarchyDict[node2add.tag] ?? -1} > ${hirarchyDict[tree.children.last.ogTag] ?? -1}');
          print("-1 ${tree.children.last.ogTag}");
          return;
        }

        _add2Tree(tree.children.last, node2add);
      } else if ((hirarchyDict[node2add.tag] ?? -1) ==
          (hirarchyDict[tree.children.last.ogTag] ?? -1)) {
        // print("equals??");
        tree.children.add(newNode);
        newNode.parent = tree;
      }
    }
  }

  void _markdown2Tree(String text) {
    print("started markdown2tree");
    final List<md.Node> nakedList = md.Document().parseLines(text.split('\n'));
    List<String> pList = [];
    List<String> h1List = [];
    List<String> h2List = [];
    List<String> h3List = [];
    List<String> h4List = [];
    List<String> h5List = [];
    List<String> h6List = [];

    for (var node in nakedList) {
      //maybe do an add function, but isn't this it?
      if (node is md.Element) {
        // print(node.textContent);
        AugmentTree temp = AugmentTree();
        temp.data = node.textContent;
        temp.ogTag = node.tag;
        if (node.tag == 'h1') {
          h1List.add(node.textContent);
          _add2Tree(zoomTreeRoot, node);
        } else if (node.tag == 'h2') {
          // i dont add any since i dont have it, maybe the function makes sense
          h2List.add(node.textContent);
          _add2Tree(zoomTreeRoot, node); // fix this
        } else if (node.tag == 'h3') {
          h3List.add(node.textContent);
          _add2Tree(zoomTreeRoot, node);
        } else if (node.tag == 'h4') {
          h4List.add(node.textContent); //this broke it
          _add2Tree(zoomTreeRoot, node); // change to temp
        } else if (node.tag == 'h5') {
          h5List.add(node.textContent);
          print(node.textContent);
          _add2Tree(zoomTreeRoot, node);
        } else if (node.tag == 'h6') {
          h6List.add(node.textContent);
          _add2Tree(zoomTreeRoot, node); // fix this
        } else if (node.tag == 'p' || node.tag == 'ul' || node.tag == 'li') {
          pList.add(node.textContent);
          _add2Tree(zoomTreeRoot, node); // fix this
        }
      }
    }

    this.sentinel = [h1List, h2List, h3List, h4List, h5List, h6List, pList];
    sentinel.removeWhere((hList) => hList.isEmpty);
    currentZoomNode = zoomTreeRoot;
    if (!mounted) return;
    setState(() {
      _isLoaded = true;
    });
  }

  void handleKeyDownMD(web.Event event) async {
    final keyEvent = event as web.KeyboardEvent;

    if (!mounted) return;
    if (keyEvent.key == 'a') {
      print("key a");
      setState(() {
        level = (level - 1).clamp(0, sentinel.length - 1);
      });
    } else if (keyEvent.key == "b") {
      print("b");
      setState(() {
        level = (level + 1).clamp(0, sentinel.length - 1);
      });
    }
  }

  void _goToChildren(int index) async {
    final target = currentZoomNode.children[index];
    if (target.children.isNotEmpty) {
      setState(() {
        currentZoomNode = target;
      });
    } else {
      print("This child has no further children.");
    }
  }

  void _goToParent() async {
    if (currentZoomNode.parent != null) {
      setState(() {
        currentZoomNode = currentZoomNode.parent!;
      });
    } else {
      print("Already at root.");
    }
  }

  void _serializableData(String threadID) async {
    emailsInThread = await ApiService().threadsInSerializable(threadID);
    print("done thread serializable");
    if (!mounted) return;
    setState(() {
      _isLoaded = true;
    });
  }

  void handleKeyDownHTML(web.Event event) {
    final keyEvent = event as web.KeyboardEvent;

    if (keyEvent.key == 'G') {
      print('You pressed the "G" key!');
      final rightPurpleNums = web.document.getElementsByClassName("right");
      _CollapsableEmailsState.right = !_CollapsableEmailsState.right;
      final newOpacity = _CollapsableEmailsState.right ? '1.0' : '0.0';
      for (int i = 0; i < rightPurpleNums.length; i++) {
        final currentElement = rightPurpleNums.item(i) as web.HTMLElement;
        currentElement.style.opacity = newOpacity;
      }
    } else if (keyEvent.key == 'H') {
      print('You pressed the "H" key!');
      final leftPurpleNums = web.document.getElementsByClassName("left");
      _CollapsableEmailsState.left = !_CollapsableEmailsState.left;
      final newOpacity = _CollapsableEmailsState.left ? '1.0' : '0.0';
      for (int i = 0; i < leftPurpleNums.length; i++) {
        final currentElement = leftPurpleNums.item(i) as web.HTMLElement;
        currentElement.style.opacity = newOpacity;
      }
    } else if (keyEvent.key == 'm') {
      print("you pressed 'm'");
      final purpleNums = web.document.getElementsByClassName("purplenumber");
      _CollapsableEmailsState.left = true;
      _CollapsableEmailsState.right = true;

      for (int i = 0; i < purpleNums.length; i++) {
        final currentElement = purpleNums.item(i) as web.HTMLElement;
        currentElement.style.opacity = '1.0';
      }
    } else if (keyEvent.key == 'n') {
      print("you pressed 'n'");
      final purpleNums = web.document.getElementsByClassName("purplenumber");
      _CollapsableEmailsState.left = false;
      _CollapsableEmailsState.right = false;

      for (int i = 0; i < purpleNums.length; i++) {
        final currentElement = purpleNums.item(i) as web.HTMLElement;
        currentElement.style.opacity = '0.0';
      }
    } else if (keyEvent.key == 'w') {
      print("you pressed 'w'");
    }
  }

  void _keyListener() {
    if (_isListenerRegistered) return;
    _isListenerRegistered = true;

    // Convert the top-level function to JS-compatible
    // _listener = handleKeyDownHTML.toJS;
    _listener = handleKeyDownMD.toJS;

    web.window.document.addEventListener('keydown', _listener!);
  }

  Widget _buildForZooms({Key? key}) {
    if (!_isLoaded) {
      return const Center(child: CircularProgressIndicator()); // loading screen
    }
    final canZoomOut = currentZoomNode.parent != null;

    return ListView.builder(
      key: key,
      itemCount: currentZoomNode.children.length,
      itemBuilder: (context, index) {
        final childNode = currentZoomNode.children[index];
        final canZoomIn = childNode.children.isNotEmpty;

        return Padding(
          padding: const EdgeInsets.symmetric(horizontal: 12.0, vertical: 6.0),
          child: Material(
            elevation: 1,
            borderRadius: BorderRadius.circular(12),
            color: Theme.of(context).colorScheme.surface,
            surfaceTintColor: Theme.of(context).colorScheme.surfaceBright,
            child: Padding(
              padding: const EdgeInsets.all(16.0),
              child: Row(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: [
                  Wrap(
                    spacing: 4.0,
                    children: [
                      OutlinedButton(
                        onPressed:
                            canZoomOut ? () => _goToParent() : null,
                        child: Icon(Icons.north_west_sharp),
                      ),
                      OutlinedButton(
                        onPressed:
                            canZoomIn ? () => _goToChildren(index) : null,
                        child: Icon(Icons.south_east_sharp),
                      ),
                    ],
                  ),
                  SizedBox(width: 12.0),
                  Expanded(
                    child: MarkdownBlock(
                      data: currentZoomNode
                          .children[index].data, // one string of markdown
                      config: MarkdownConfig
                          .darkConfig, // or lightConfig depending on theme
                    ),
                  ),
                ],
              ),
            ),
          ),
        );
      },
    );
  }

  @override
  Widget build(BuildContext context) {
    return _isLoaded
        ? Column(children: [
            Expanded(
              child: ListView.builder(
                itemCount: emailsInThread.length,
                itemBuilder: (context, index) {
                  final isExpanded = _expandedEmails
                      .contains(index); //check if email is expanded
                  return Column(
                    children: [
                      ListTile(
                        title: Text(emailsInThread[index].from),
                        trailing: Text(emailsInThread[index].date),
                        onTap: () {
                          setState(() {
                            if (isExpanded) {
                              _expandedEmails.remove(index);
                            } else {
                              _expandedEmails.add(index);
                            }
                          });
                        },
                      ),
                      if (isExpanded)
                        ConstrainedBox(
                          constraints: BoxConstraints(
                            minHeight: 100,
                            maxHeight: MediaQuery.of(context).size.height * 0.6,
                          ),
                          child: _buildForZooms(key: ValueKey(currentZoomNode)),
                        ),
                      Divider(),
                    ],
                  );
                },
              ),
            ),
          ])
        : const Center(child: CircularProgressIndicator());
  }
}