import 'package:flutter/material.dart';
import 'package:flutter/services.dart';
import 'package:lucide_icons_flutter/lucide_icons.dart';

import '../tokens.dart';
import 'cards.dart';

/// Labelled field.
///
/// White with a hairline at rest, and on focus the edge goes crimson with a
/// 3pt wash ring around it. The ring is the whole reason this is a container
/// rather than an `InputDecoration`: it is a spread shadow in the brand's
/// lightest tint, which no `InputBorder` can draw, and it is what makes the
/// focused field read as lit rather than merely outlined.
///
/// [optional] appends the grey marker that keeps skippable destination and
/// recipient fields honestly signposted.
class DmTextField extends StatefulWidget {
  const DmTextField({
    super.key,
    this.label,
    required this.controller,
    this.hint,
    this.optional = false,
    this.keyboardType,
    this.maxLength,
    this.maxLines = 1,
    this.prefix,
    this.textInputAction,
    this.onSubmitted,
    this.autofocus = false,
    this.digitsOnly = false,
    this.mono = false,
    this.onClear,
  });

  /// The caption above the field, or null for a field that stands alone.
  ///
  /// Nullable because a screen whose heading already says what to type does
  /// not need to say it again directly underneath — "Enter your mobile number"
  /// above a field captioned "Phone number" is one sentence printed twice.
  final String? label;
  final TextEditingController controller;
  final String? hint;
  final bool optional;
  final TextInputType? keyboardType;
  final int? maxLength;
  final int maxLines;
  final String? prefix;
  final TextInputAction? textInputAction;
  final ValueChanged<String>? onSubmitted;
  final bool autofocus;
  final bool digitsOnly;

  /// Sets the value in mono — a pincode or a phone number, where the customer
  /// checks the digits back.
  final bool mono;

  /// Shows a clear button on the right when non-null.
  final VoidCallback? onClear;

  @override
  State<DmTextField> createState() => _DmTextFieldState();
}

class _DmTextFieldState extends State<DmTextField> {
  final FocusNode _node = FocusNode();

  @override
  void initState() {
    super.initState();
    _node.addListener(() => setState(() {}));
  }

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

  @override
  Widget build(BuildContext context) {
    final focused = _node.hasFocus;
    final textStyle = widget.mono
        ? DmText.monoLg.copyWith(fontSize: 15.5, color: DmColors.ink)
        : DmText.field;

    return Padding(
      padding: const EdgeInsets.only(bottom: 14),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          if (widget.label != null) ...[
            Text.rich(
              TextSpan(
                style: DmText.label,
                children: [
                  TextSpan(text: widget.label),
                  if (widget.optional)
                    const TextSpan(
                      text: '   Optional',
                      style: TextStyle(
                        color: DmColors.ink4,
                        fontWeight: FontWeight.w500,
                      ),
                    ),
                ],
              ),
            ),
            const SizedBox(height: 8),
          ],
          AnimatedContainer(
            duration: DmMotion.fast,
            curve: DmMotion.ease,
            constraints: BoxConstraints(
              minHeight: widget.maxLines > 1 ? 0 : DmSpace.field,
            ),
            decoration: BoxDecoration(
              color: DmColors.surface,
              borderRadius: DmRadius.all(DmRadius.sm),
              border: Border.all(
                color: focused ? DmColors.brand : DmColors.border,
              ),
              boxShadow: focused
                  ? const [
                      BoxShadow(
                        color: DmColors.brandSoft,
                        spreadRadius: 3,
                        blurRadius: 0,
                      ),
                    ]
                  : null,
            ),
            child: Row(
              crossAxisAlignment: widget.maxLines > 1
                  ? CrossAxisAlignment.start
                  : CrossAxisAlignment.center,
              children: [
                if (widget.prefix != null) ...[
                  Padding(
                    padding: const EdgeInsets.fromLTRB(15, 0, 12, 0),
                    child: Text(
                      widget.prefix!,
                      style: DmText.field.copyWith(
                        color: DmColors.ink2,
                        fontWeight: FontWeight.w700,
                      ),
                    ),
                  ),
                  // A hairline between the country code and the number: they
                  // are two different things and reading them as one string is
                  // how a digit gets lost.
                  Container(width: 1, height: 22, color: DmColors.border),
                ],
                Expanded(
                  child: TextField(
                    controller: widget.controller,
                    focusNode: _node,
                    keyboardType: widget.keyboardType,
                    maxLines: widget.maxLines,
                    autofocus: widget.autofocus,
                    textInputAction: widget.textInputAction,
                    onSubmitted: widget.onSubmitted,
                    cursorColor: DmColors.brand,
                    cursorRadius: const Radius.circular(2),
                    style: textStyle,
                    inputFormatters: [
                      if (widget.maxLength != null)
                        LengthLimitingTextInputFormatter(widget.maxLength),
                      if (widget.digitsOnly)
                        FilteringTextInputFormatter.digitsOnly,
                    ],
                    decoration: InputDecoration(
                      isDense: true,
                      hintText: widget.hint,
                      hintStyle: DmText.field.copyWith(
                        color: DmColors.ink3,
                        fontWeight: FontWeight.w500,
                      ),
                      filled: false,
                      counterText: '',
                      contentPadding: EdgeInsets.fromLTRB(
                        widget.prefix == null ? 15 : 12,
                        widget.maxLines > 1 ? 15 : 14,
                        8,
                        widget.maxLines > 1 ? 15 : 14,
                      ),
                      border: InputBorder.none,
                      enabledBorder: InputBorder.none,
                      focusedBorder: InputBorder.none,
                    ),
                  ),
                ),
                if (widget.onClear != null)
                  Padding(
                    padding: const EdgeInsets.only(right: 6),
                    child: InkWell(
                      onTap: widget.onClear,
                      borderRadius: DmRadius.all(DmRadius.xs),
                      child: const SizedBox(
                        width: 34,
                        height: 34,
                        child: Icon(LucideIcons.x, size: 17, color: DmColors.ink3),
                      ),
                    ),
                  ),
              ],
            ),
          ),
        ],
      ),
    );
  }
}

/// A settings row: label left, value or control right.
class DmRow extends StatelessWidget {
  const DmRow({
    super.key,
    required this.label,
    this.value,
    this.trailing,
    this.onTap,
    this.showChevron = false,
    this.icon,
  });

  final String label;
  final String? value;
  final Widget? trailing;
  final VoidCallback? onTap;
  final bool showChevron;

  /// The glyph in the row's leading tile. Account's rows all carry one, so the
  /// list can be scanned by shape before it is read.
  final IconData? icon;

  @override
  Widget build(BuildContext context) {
    return Material(
      color: Colors.transparent,
      child: InkWell(
        onTap: onTap,
        splashColor: DmColors.brandSoft,
        highlightColor: DmColors.brandSoft.withValues(alpha: 0.5),
        child: Container(
          constraints: const BoxConstraints(minHeight: 56),
          padding: const EdgeInsets.fromLTRB(16, 11, 16, 11),
          child: Row(
            children: [
              if (icon != null) ...[
                DmTile(icon: icon, tone: DmTileTone.wash),
                const SizedBox(width: 12),
              ],
              // The label is what the row IS, so it never wraps and never
              // gives up width; the value is context and ellipsizes. A saved
              // address as a value would otherwise push "Saved addresses" onto
              // two lines.
              Expanded(
                flex: 3,
                child: Text(
                  label,
                  style: DmText.cardTitle,
                  maxLines: 1,
                  overflow: TextOverflow.ellipsis,
                ),
              ),
              if (value != null) ...[
                const SizedBox(width: 10),
                Flexible(
                  flex: 2,
                  child: Text(
                    value!,
                    style: DmText.value,
                    textAlign: TextAlign.right,
                    maxLines: 1,
                    overflow: TextOverflow.ellipsis,
                  ),
                ),
              ],
              ?trailing,
              if (showChevron) ...[
                const SizedBox(width: 8),
                const Icon(
                  LucideIcons.chevronRight,
                  size: 18,
                  color: DmColors.ink4,
                ),
              ],
            ],
          ),
        ),
      ),
    );
  }
}

/// Card that rules a group of [DmRow]s together.
class DmRowGroup extends StatelessWidget {
  const DmRowGroup({super.key, required this.children});

  final List<Widget> children;

  @override
  Widget build(BuildContext context) => DmCard(children: children);
}

/// Switch in brand colours.
class DmSwitch extends StatelessWidget {
  const DmSwitch({super.key, required this.value, required this.onChanged});

  final bool value;
  final ValueChanged<bool> onChanged;

  @override
  Widget build(BuildContext context) {
    return Switch.adaptive(
      value: value,
      onChanged: (v) {
        HapticFeedback.selectionClick();
        onChanged(v);
      },
      activeThumbColor: Colors.white,
      activeTrackColor: DmColors.brand,
      inactiveThumbColor: Colors.white,
      inactiveTrackColor: DmColors.border,
      trackOutlineColor: WidgetStateProperty.all(Colors.transparent),
    );
  }
}