import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:stacked/stacked.dart';

import '../../about/external/data/Group.dart';
import '../../about/external/data/GroupGoal.dart';
import '../../about/external/data/GroupMember.dart';
import '../../about/external/data/GroupObjective.dart';
import '../../about/external/initial/NudgeRequest.dart';
import '../../about/external/initial/ObjectiveProgressRequest.dart';
import '../../about/internal/application/NotificationType.dart';
import '../../about/internal/application/TextType.dart';
import '../../configs/Navigator.dart';
import '../../designs/Component.dart';
import '../../designs/MemberAvatar.dart';
import '../../designs/Responsive.dart';
import '../../designs/Shell.dart';
import '../../designs/buttons/Buttons.dart';
import '../../designs/input/InputFields.dart';
import '../../designs/text/Text.dart';
import '../../utils/Colors.dart';
import '../../utils/CommonUtils.dart';
import 'ConnectGroupDetail.dart';
import 'GroupChat.dart';
import 'GroupDetail.dart';
import 'GroupGoalEditor.dart';
import 'ViewGroupDetail.dart';

class GroupDetailState extends State<GroupDetail>
    implements ConnectGroupDetail {
  ViewGroupDetail? _model;

  late Group _group;

  /// Members nudged from this screen, so the button reads "Nudged" after.
  final Set<String> _nudged = <String>{};

  final TextEditingController _amount = TextEditingController();

  final TextEditingController _note = TextEditingController();

  @override
  void initState() {
    super.initState();
    _group = widget.group;
  }

  @override
  void dispose() {
    _amount.dispose();
    _note.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    return ViewModelBuilder<ViewGroupDetail>.reactive(
      viewModelBuilder: () => ViewGroupDetail(context, this),
      onViewModelReady: (viewModel) {
        _model = viewModel;
        _initiate();
      },
      builder: (context, viewModel, child) => LayoutBuilder(
        builder: (BuildContext context, BoxConstraints constraints) {
          return Responsive(
            mobile: _mobileView(constraints),
            tablet: _mobileView(constraints),
            desktop: _mobileView(constraints),
          );
        },
      ),
    );
  }

  void _initiate() {
    _model?.loadGroup(widget.group.id);
  }

  Color get _accent => goalColor(_group.colourHex);

  // ── Handlers ──────────────────────────────────────────────────────────────

  void _onBack() {
    Navigator.pop(context, true);
  }

  void _onOpenChat() async {
    await GroundedNavigation()
        .navigateToPageWithData(GroupChat(group: _group), context);
    _model?.loadGroup(_group.id, quiet: true);
  }

  void _onAddGoal() async {
    final result = await GroundedNavigation()
        .navigateToPageWithData(GroupGoalEditor(group: _group), context);

    if (result == true) {
      _model?.loadGroup(_group.id, quiet: true);
    }
  }

  void _onCopyCode() async {
    await Clipboard.setData(ClipboardData(text: _group.inviteCode));
    _model?.showApplicationNotification(
      NotificationType.success,
      "Code copied",
      "Send ${_group.inviteCode} to whoever should join. They enter it under Groups → Join with a code.",
      true,
      true,
      null,
    );
  }

  void _onNudge(GroupMember member) {
    _model?.nudge(
        NudgeRequest(groupId: _group.id, memberId: member.id), member.name);
  }

  void _onNudgeEveryone() {
    _model?.nudge(NudgeRequest(groupId: _group.id), "everyone");
  }

  void _onLog(GroupGoal goal, GroupObjective objective) {
    _amount.text = "";
    _note.text = "";

    showModalBottomSheet(
      context: context,
      isScrollControlled: true,
      backgroundColor: colorWhite,
      builder: (sheetContext) => _logSheet(sheetContext, goal, objective),
    );
  }

  void _onQuickAmount(double value) {
    _amount.text = formatAmount(value).replaceAll(",", "");
  }

  void _onSubmitLog(BuildContext sheetContext, GroupGoal goal,
      GroupObjective objective) {
    final double amount = double.tryParse(_amount.text.trim()) ?? 0;
    if (amount <= 0) {
      return;
    }

    Navigator.pop(sheetContext);

    _model?.logProgress(
      ObjectiveProgressRequest(
        groupId: _group.id,
        goalId: goal.id,
        objectiveId: objective.id,
        amount: amount,
        note: _note.text.trim(),
      ),
      "${formatAmount(amount)} ${objective.unit} on ${objective.title}",
    );
  }

  void _onLeave() {
    _model?.showApplicationNotification(
      NotificationType.warning,
      "Leave ${_group.name}?",
      "You stop seeing the shared goals and the chat. What you logged stays in the group's totals.",
      true,
      true,
      null,
      action: "Leave",
      positiveAction: _onConfirmLeave,
    );
  }

  void _onConfirmLeave() {
    Navigator.pop(context);
    _model?.leave(_group.id);
  }

  // ── Views ─────────────────────────────────────────────────────────────────

  Widget _mobileView(BoxConstraints constraints) {
    final List<GroupMember> ranked = List<GroupMember>.from(_group.members)
      ..sort((a, b) => b.keptRate.compareTo(a.keptRate));

    return Sheet(
      eyebrow: "${_group.members.length} members",
      title: _group.name,
      onBack: _onBack,
      scene: goalScene(_accent),
      sceneSeed: sceneSeed(_group.name),
      action: chromeAction(CupertinoIcons.chat_bubble_2_fill, _onOpenChat),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        mainAxisSize: MainAxisSize.min,
        children: [
          if (_group.description.isNotEmpty) ...[
            text(_group.description, 15, TextType.Regular,
                color: colorGrey2, height: 1.55),
            const SizedBox(height: 22),
          ],
          _statsRow(),
          const SizedBox(height: 20),
          _chatCard(),
          const SizedBox(height: 30),
          sectionBreak(
            "Shared goals",
            caption: "${_group.goals.length} on the go",
            trailing: textButton("+ Add", _onAddGoal,
                color: colorInk, textSize: 14, type: TextType.Medium),
          ),
          if (_group.goals.isEmpty)
            emptyState(
              CupertinoIcons.flag,
              "Nothing shared yet",
              "Add a goal and split it into objectives everyone can log toward, like kilometres, pages or sessions.",
            )
          else
            ..._group.goals.map(_goalCard),
          const SizedBox(height: 30),
          sectionBreak("Leaderboard",
              caption: "kept, last 7 days",
              trailing: textButton("Nudge all", _onNudgeEveryone,
                  color: colorInk, textSize: 14, type: TextType.Medium)),
          for (int index = 0; index < ranked.length; index++)
            _memberRow(index + 1, ranked[index]),
          const SizedBox(height: 26),
          Center(
            child: textButton("Leave group", _onLeave,
                color: colorDestructive, textSize: 13),
          ),
        ],
      ),
    );
  }

  Widget _statsRow() {
    final double average = _group.members.isEmpty
        ? 0
        : _group.members
                .map((member) => member.keptRate)
                .reduce((a, b) => a + b) /
            _group.members.length;

    return card(
      padding: const EdgeInsets.fromLTRB(20, 18, 12, 18),
      child: Row(
        children: [
          Expanded(
            child: labelled("Together", "${(_group.progress * 100).round()}%",
                valueSize: 26, valueType: TextType.Light),
          ),
          Expanded(
            child: labelled("Kept avg", "${(average * 100).round()}%",
                valueSize: 26, valueType: TextType.Light),
          ),
          GestureDetector(
            onTap: _onCopyCode,
            behavior: HitTestBehavior.opaque,
            child: Container(
              padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 10),
              color: colorAmbientMid,
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                mainAxisSize: MainAxisSize.min,
                children: [
                  Row(
                    mainAxisSize: MainAxisSize.min,
                    children: [
                      text("INVITE", 9, TextType.Bold,
                          color: colorGrey2, letterSpacing: 1.0),
                      const SizedBox(width: 6),
                      Icon(CupertinoIcons.doc_on_doc,
                          size: 12, color: colorGrey2),
                    ],
                  ),
                  const SizedBox(height: 4),
                  text(_group.inviteCode, 18, TextType.Medium,
                      color: colorInk, letterSpacing: 1.5),
                ],
              ),
            ),
          ),
        ],
      ),
    );
  }

  /// The way into the chat: the last line said and how much is unread.
  Widget _chatCard() {
    return GestureDetector(
      onTap: _onOpenChat,
      child: Container(
        padding: const EdgeInsets.fromLTRB(20, 18, 16, 18),
        decoration: const BoxDecoration(
          gradient: LinearGradient(
            begin: Alignment.topLeft,
            end: Alignment.bottomRight,
            colors: <Color>[colorNightLift, colorNight],
          ),
          boxShadow: [
            BoxShadow(
              color: Color(0x332A3A30),
              blurRadius: 24,
              offset: Offset(0, 10),
            ),
          ],
        ),
        child: Row(
          children: [
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                mainAxisSize: MainAxisSize.min,
                children: [
                  Row(
                    children: [
                      Icon(CupertinoIcons.chat_bubble_2_fill,
                          size: 16, color: colorLime),
                      const SizedBox(width: 8),
                      text("Group chat", 14, TextType.Medium,
                          color: colorLime),
                      if (_group.unread > 0) ...[
                        const SizedBox(width: 10),
                        Container(
                          padding: const EdgeInsets.symmetric(
                              horizontal: 7, vertical: 3),
                          color: colorLime,
                          child: text("${_group.unread} new", 10,
                              TextType.Medium,
                              color: colorNight),
                        ),
                      ],
                    ],
                  ),
                  const SizedBox(height: 10),
                  text(
                    _group.lastMessage.isEmpty
                        ? "Say hello. Check-ins and nudges show up here too."
                        : "${_group.lastAuthor}: ${_group.lastMessage}",
                    15,
                    TextType.Regular,
                    color: colorWhite,
                    maxLines: 2,
                    overflow: TextOverflow.ellipsis,
                    height: 1.45,
                  ),
                ],
              ),
            ),
            const SizedBox(width: 12),
            Container(
              width: 46,
              height: 46,
              color: colorWhite.withValues(alpha: 0.12),
              child: Icon(CupertinoIcons.arrow_right,
                  size: 20, color: colorWhite),
            ),
          ],
        ),
      ),
    );
  }

  /// A shared goal: its overall bar, then each objective with the group's
  /// total, your share, and a button to log more.
  Widget _goalCard(GroupGoal goal) {
    final Color tone =
        goal.colourHex.isEmpty ? _accent : goalColor(goal.colourHex);

    return Container(
      margin: const EdgeInsets.only(bottom: 14),
      child: card(
        padding: EdgeInsets.zero,
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.stretch,
          mainAxisSize: MainAxisSize.min,
          children: [
            Container(height: 6, color: tone),
            Padding(
              padding: const EdgeInsets.fromLTRB(20, 18, 20, 6),
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.stretch,
                mainAxisSize: MainAxisSize.min,
                children: [
                  Row(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Expanded(
                        child: text(goal.title, 19, TextType.Medium,
                            color: colorInk),
                      ),
                      const SizedBox(width: 10),
                      text("${(goal.progress * 100).round()}%", 22,
                          TextType.Light,
                          color: colorInk),
                    ],
                  ),
                  const SizedBox(height: 4),
                  text(
                    [
                      "${goal.completeObjectives}/${goal.objectives.length} objectives met",
                      goal.targetDate == null
                          ? "no deadline"
                          : targetLabel(goal.targetDate),
                    ].join(" · "),
                    12,
                    TextType.Regular,
                    color: colorGrey2,
                  ),
                  const SizedBox(height: 12),
                  meter(goal.progress,
                      fill: tone, track: tone.withValues(alpha: 0.14), height: 6),
                  const SizedBox(height: 8),
                ],
              ),
            ),
            for (GroupObjective objective in goal.objectives)
              _objectiveRow(goal, objective, tone),
          ],
        ),
      ),
    );
  }

  Widget _objectiveRow(GroupGoal goal, GroupObjective objective, Color tone) {
    return Container(
      padding: const EdgeInsets.fromLTRB(20, 14, 14, 16),
      decoration: BoxDecoration(
        border: Border(top: BorderSide(color: colorBorder)),
      ),
      child: Row(
        children: [
          Expanded(
            child: Column(
              crossAxisAlignment: CrossAxisAlignment.start,
              mainAxisSize: MainAxisSize.min,
              children: [
                Row(
                  children: [
                    if (objective.complete) ...[
                      Icon(CupertinoIcons.checkmark_seal_fill,
                          size: 15, color: colorPositive),
                      const SizedBox(width: 6),
                    ],
                    Flexible(
                      child: text(objective.title, 15, TextType.Medium,
                          color: colorInk,
                          maxLines: 1,
                          overflow: TextOverflow.ellipsis),
                    ),
                  ],
                ),
                const SizedBox(height: 4),
                text(
                  "${formatAmount(objective.current)} / ${formatAmount(objective.target)} ${objective.unit}",
                  13,
                  TextType.Regular,
                  color: colorGrey2,
                ),
                const SizedBox(height: 8),
                meter(objective.progress,
                    fill: tone, track: tone.withValues(alpha: 0.12), height: 4),
                const SizedBox(height: 6),
                text("You: ${formatAmount(objective.mine)} ${objective.unit}",
                    12, TextType.Medium,
                    color: tone),
              ],
            ),
          ),
          const SizedBox(width: 14),
          GestureDetector(
            onTap: () => _onLog(goal, objective),
            child: Container(
              padding: const EdgeInsets.symmetric(horizontal: 14, vertical: 12),
              color: colorNight,
              child: Row(
                mainAxisSize: MainAxisSize.min,
                children: [
                  Icon(CupertinoIcons.add, size: 16, color: colorLime),
                  const SizedBox(width: 6),
                  text("Log", 14, TextType.Medium, color: colorWhite),
                ],
              ),
            ),
          ),
        ],
      ),
    );
  }

  Widget _memberRow(int rank, GroupMember member) {
    final bool nudged = _nudged.contains(member.id);
    final bool quiet = member.lastCheckIn == null ||
        DateTime.now().difference(member.lastCheckIn!).inHours >= 24;

    return Container(
      margin: const EdgeInsets.only(bottom: 10),
      child: card(
        padding: const EdgeInsets.fromLTRB(14, 12, 12, 12),
        child: Row(
          children: [
            SizedBox(
              width: 24,
              child: text("$rank", 16, TextType.Medium,
                  color: rank == 1 ? colorInk : colorGrey2),
            ),
            memberAvatar(member.name, 46),
            const SizedBox(width: 12),
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                mainAxisSize: MainAxisSize.min,
                children: [
                  Row(
                    children: [
                      Flexible(
                        child: text(
                            member.me ? "${member.name} (you)" : member.name,
                            16,
                            TextType.Medium,
                            color: colorInk,
                            maxLines: 1,
                            overflow: TextOverflow.ellipsis),
                      ),
                      if (member.owner) ...[
                        const SizedBox(width: 6),
                        Icon(CupertinoIcons.star_fill,
                            size: 12, color: colorBarStandard),
                      ],
                    ],
                  ),
                  const SizedBox(height: 4),
                  Row(
                    children: [
                      Icon(CupertinoIcons.flame_fill,
                          size: 12, color: colorBarNonNegotiable),
                      const SizedBox(width: 3),
                      text("${member.streak}d", 12, TextType.Regular,
                          color: colorGrey2),
                      const SizedBox(width: 10),
                      text(
                        quiet
                            ? "quiet ${member.lastCheckIn == null ? "" : _ago(member.lastCheckIn!)}"
                            : "checked in ${_ago(member.lastCheckIn!)}",
                        12,
                        TextType.Regular,
                        color: quiet ? colorStandingGrounded : colorGrey2,
                      ),
                    ],
                  ),
                ],
              ),
            ),
            text("${(member.keptRate * 100).round()}%", 20, TextType.Light,
                color: colorInk),
            if (!member.me) ...[
              const SizedBox(width: 10),
              GestureDetector(
                onTap: nudged ? null : () => _onNudge(member),
                child: Container(
                  width: 44,
                  height: 44,
                  color: nudged ? colorAmbientMid : colorNight,
                  child: Icon(
                    nudged
                        ? CupertinoIcons.checkmark
                        : CupertinoIcons.hand_point_right_fill,
                    size: 18,
                    color: nudged ? colorGrey2 : colorLime,
                  ),
                ),
              ),
            ],
          ],
        ),
      ),
    );
  }

  /// Log progress: an amount (with one-tap presets that suit the unit) and
  /// an optional note that rides along into the chat.
  Widget _logSheet(BuildContext sheetContext, GroupGoal goal,
      GroupObjective objective) {
    final List<double> presets = _presets(objective.unit);

    return Padding(
      padding: EdgeInsets.fromLTRB(20, 16, 20,
          MediaQuery.of(sheetContext).viewInsets.bottom + 28),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.stretch,
        mainAxisSize: MainAxisSize.min,
        children: [
          Center(child: Container(width: 40, height: 4, color: colorGrabber)),
          const SizedBox(height: 18),
          text("LOG PROGRESS", 10, TextType.Bold,
              color: colorGrey2, letterSpacing: 1.2),
          const SizedBox(height: 6),
          text(objective.title, 24, TextType.Medium, color: colorInk),
          const SizedBox(height: 4),
          text(
              "${formatAmount(objective.current)} of ${formatAmount(objective.target)} ${objective.unit} so far",
              13,
              TextType.Regular,
              color: colorGrey2),
          const SizedBox(height: 18),
          Row(
            children: [
              for (double preset in presets) ...[
                Expanded(
                  child: GestureDetector(
                    onTap: () => _onQuickAmount(preset),
                    child: Container(
                      padding: const EdgeInsets.symmetric(vertical: 14),
                      alignment: Alignment.center,
                      color: colorAmbientMid,
                      child: text("+${formatAmount(preset)}", 15,
                          TextType.Medium,
                          color: colorInk),
                    ),
                  ),
                ),
                if (preset != presets.last) const SizedBox(width: 8),
              ],
            ],
          ),
          const SizedBox(height: 16),
          inputField(
            "Amount (${objective.unit})",
            _amount,
            hint: "How much?",
            keyboard: const TextInputType.numberWithOptions(decimal: true),
            formatters: <TextInputFormatter>[
              FilteringTextInputFormatter.allow(RegExp(r"[0-9.]")),
            ],
          ),
          const SizedBox(height: 14),
          inputField("Note", _note, hint: "Optional: posted with the check-in"),
          const SizedBox(height: 22),
          roundedCornerButton("Log it",
              () => _onSubmitLog(sheetContext, goal, objective),
              icon: CupertinoIcons.checkmark),
        ],
      ),
    );
  }

  List<double> _presets(String unit) {
    switch (unit.toLowerCase()) {
      case "steps":
        return <double>[1000, 5000, 10000];
      case "words":
        return <double>[250, 500, 1000];
      case "hours":
        return <double>[0.5, 1, 2];
      case "km":
        return <double>[3, 5, 10];
      default:
        return <double>[1, 2, 5];
    }
  }

  String _ago(DateTime moment) {
    final Duration gap = DateTime.now().difference(moment);
    if (gap.inMinutes < 60) return "${gap.inMinutes.clamp(1, 59)}m ago";
    if (gap.inHours < 24) return "${gap.inHours}h ago";
    return "${gap.inDays}d ago";
  }

  // ── ConnectGroupDetail ────────────────────────────────────────────────────

  @override
  void onGroupLoaded(Group group) {
    setState(() {
      _group = group;
    });
  }

  @override
  void onProgressLogged(Group group, String summary) {
    setState(() {
      _group = group;
    });
    _model?.showApplicationNotification(
      NotificationType.success,
      "Logged",
      "$summary. The group sees it in the chat.",
      true,
      true,
      null,
    );
  }

  @override
  void onNudged(String who) {
    setState(() {
      for (GroupMember member in _group.members) {
        if (who == "everyone" ? !member.me : member.name == who) {
          _nudged.add(member.id);
        }
      }
    });
  }

  @override
  void onLeft() {
    Navigator.pop(context, true);
  }
}