import 'package:flutter/material.dart';

import '../../models/documents/attribute.dart';
import '../../models/documents/style.dart';
import '../../models/structs/vertical_spacing.dart';
import '../../utils/platform.dart';
import '../style_widgets/checkbox_point.dart';

class QuillStyles extends InheritedWidget {
  const QuillStyles({
    required this.data,
    required super.child,
    super.key,
  });

  final DefaultStyles data;

  @override
  bool updateShouldNotify(QuillStyles oldWidget) {
    return data != oldWidget.data;
  }

  static DefaultStyles? getStyles(BuildContext context, bool nullOk) {
    final widget = context.dependOnInheritedWidgetOfExactType<QuillStyles>();
    if (widget == null && nullOk) {
      return null;
    }
    assert(widget != null);
    return widget!.data;
  }
}

/// Style theme applied to a block of rich text, including single-line
/// paragraphs.
@immutable
class DefaultTextBlockStyle {
  const DefaultTextBlockStyle(
    this.style,
    this.verticalSpacing,
    this.lineSpacing,
    this.decoration,
  );

  /// Base text style for a text block.
  final TextStyle style;

  /// Vertical spacing around a text block.
  final VerticalSpacing verticalSpacing;

  /// Vertical spacing for individual lines within a text block.
  ///
  final VerticalSpacing lineSpacing;

  /// Decoration of a text block.
  ///
  /// Decoration, if present, is painted in the content area, excluding
  /// any [spacing].
  final BoxDecoration? decoration;
}

/// Theme data for inline code.
class InlineCodeStyle {
  InlineCodeStyle({
    required this.style,
    this.header1,
    this.header2,
    this.header3,
    this.header4,
    this.header5,
    this.header6,
    this.backgroundColor,
    this.radius,
  });

  /// Base text style for an inline code.
  final TextStyle style;

  /// Style override for inline code in header level 1.
  final TextStyle? header1;

  /// Style override for inline code in headings level 2.
  final TextStyle? header2;

  /// Style override for inline code in headings level 3.
  final TextStyle? header3;

  /// Style override for inline code in headings level 4.
  final TextStyle? header4;

  /// Style override for inline code in headings level 5.
  final TextStyle? header5;

  /// Style override for inline code in headings level 6.
  final TextStyle? header6;

  /// Background color for inline code.
  final Color? backgroundColor;

  /// Radius used when paining the background.
  final Radius? radius;

  /// Returns effective style to use for inline code for the specified
  /// [lineStyle].
  TextStyle styleFor(Style lineStyle) {
    if (lineStyle.containsKey(Attribute.h1.key)) {
      return header1 ?? style;
    }
    if (lineStyle.containsKey(Attribute.h2.key)) {
      return header2 ?? style;
    }
    if (lineStyle.containsKey(Attribute.h3.key)) {
      return header3 ?? style;
    }
    if (lineStyle.containsKey(Attribute.h4.key)) {
      return header4 ?? style;
    }
    if (lineStyle.containsKey(Attribute.h5.key)) {
      return header5 ?? style;
    }
    if (lineStyle.containsKey(Attribute.h6.key)) {
      return header6 ?? style;
    }
    return style;
  }

  @override
  bool operator ==(Object other) {
    if (identical(this, other)) {
      return true;
    }
    if (other is! InlineCodeStyle) {
      return false;
    }
    return other.style == style &&
        other.header1 == header1 &&
        other.header2 == header2 &&
        other.header3 == header3 &&
        other.header4 == header4 &&
        other.header5 == header5 &&
        other.header6 == header6 &&
        other.backgroundColor == backgroundColor &&
        other.radius == radius;
  }

  @override
  int get hashCode => Object.hash(style, header1, header2, header3, header4,
      header5, header6, backgroundColor, radius);
}

@immutable
class DefaultListBlockStyle extends DefaultTextBlockStyle {
  const DefaultListBlockStyle(
    super.style,
    super.verticalSpacing,
    super.lineSpacing,
    super.decoration,
    this.checkboxUIBuilder,
  );

  final QuillCheckboxBuilder? checkboxUIBuilder;
}

@immutable
class DefaultStyles {
  const DefaultStyles({
    this.h1,
    this.h2,
    this.h3,
    this.h4,
    this.h5,
    this.h6,
    this.paragraph,
    this.bold,
    this.subscript,
    this.superscript,
    this.italic,
    this.small,
    this.underline,
    this.strikeThrough,
    this.inlineCode,
    this.link,
    this.color,
    this.placeHolder,
    this.lists,
    this.quote,
    this.code,
    this.indent,
    this.align,
    this.leading,
    this.sizeSmall,
    this.sizeLarge,
    this.sizeHuge,
  });

  final DefaultTextBlockStyle? h1;
  final DefaultTextBlockStyle? h2;
  final DefaultTextBlockStyle? h3;
  final DefaultTextBlockStyle? h4;
  final DefaultTextBlockStyle? h5;
  final DefaultTextBlockStyle? h6;
  final DefaultTextBlockStyle? paragraph;
  final TextStyle? bold;
  final TextStyle? subscript;
  final TextStyle? superscript;
  final TextStyle? italic;
  final TextStyle? small;
  final TextStyle? underline;
  final TextStyle? strikeThrough;

  /// Theme of inline code.
  final InlineCodeStyle? inlineCode;
  final TextStyle? sizeSmall; // 'small'
  final TextStyle? sizeLarge; // 'large'
  final TextStyle? sizeHuge; // 'huge'
  final TextStyle? link;
  final Color? color;
  final DefaultTextBlockStyle? placeHolder;
  final DefaultListBlockStyle? lists;
  final DefaultTextBlockStyle? quote;
  final DefaultTextBlockStyle? code;
  final DefaultTextBlockStyle? indent;
  final DefaultTextBlockStyle? align;
  final DefaultTextBlockStyle? leading;

  static DefaultStyles getInstance(BuildContext context) {
    final themeData = Theme.of(context);
    final defaultTextStyle = DefaultTextStyle.of(context);
    final baseStyle = defaultTextStyle.style.copyWith(
      fontSize: 16,
      height: 1.3,
      decoration: TextDecoration.none,
    );
    const baseSpacing = VerticalSpacing(6, 0);
    String fontFamily;
    if (isAppleOS(platform: themeData.platform, supportWeb: true)) {
      fontFamily = 'Menlo';
    } else {
      fontFamily = 'Roboto Mono';
    }

    final inlineCodeStyle = TextStyle(
      fontSize: 14,
      color: themeData.colorScheme.primary.withOpacity(0.8),
      fontFamily: fontFamily,
    );

    return DefaultStyles(
        h1: DefaultTextBlockStyle(
            defaultTextStyle.style.copyWith(
              fontSize: 34,
              color: defaultTextStyle.style.color,
              letterSpacing: -1,
              height: 1,
              fontWeight: FontWeight.bold,
              decoration: TextDecoration.none,
            ),
            const VerticalSpacing(16, 0),
            const VerticalSpacing(0, 0),
            null),
        h2: DefaultTextBlockStyle(
            defaultTextStyle.style.copyWith(
              fontSize: 30,
              color: defaultTextStyle.style.color,
              letterSpacing: -0.8,
              height: 1.067,
              fontWeight: FontWeight.bold,
              decoration: TextDecoration.none,
            ),
            const VerticalSpacing(8, 0),
            const VerticalSpacing(0, 0),
            null),
        h3: DefaultTextBlockStyle(
          defaultTextStyle.style.copyWith(
            fontSize: 24,
            color: defaultTextStyle.style.color,
            letterSpacing: -0.5,
            height: 1.083,
            fontWeight: FontWeight.bold,
            decoration: TextDecoration.none,
          ),
          const VerticalSpacing(8, 0),
          const VerticalSpacing(0, 0),
          null,
        ),
        h4: DefaultTextBlockStyle(
          defaultTextStyle.style.copyWith(
            fontSize: 20,
            color: defaultTextStyle.style.color,
            letterSpacing: -0.4,
            height: 1.1,
            fontWeight: FontWeight.bold,
            decoration: TextDecoration.none,
          ),
          const VerticalSpacing(6, 0),
          const VerticalSpacing(0, 0),
          null,
        ),
        h5: DefaultTextBlockStyle(
          defaultTextStyle.style.copyWith(
            fontSize: 18,
            color: defaultTextStyle.style.color,
            letterSpacing: -0.2,
            height: 1.11,
            fontWeight: FontWeight.bold,
            decoration: TextDecoration.none,
          ),
          const VerticalSpacing(6, 0),
          const VerticalSpacing(0, 0),
          null,
        ),
        h6: DefaultTextBlockStyle(
          defaultTextStyle.style.copyWith(
            fontSize: 16,
            color: defaultTextStyle.style.color,
            letterSpacing: -0.1,
            height: 1.125,
            fontWeight: FontWeight.bold,
            decoration: TextDecoration.none,
          ),
          const VerticalSpacing(4, 0),
          const VerticalSpacing(0, 0),
          null,
        ),
        paragraph: DefaultTextBlockStyle(
          baseStyle,
          const VerticalSpacing(0, 0),
          const VerticalSpacing(0, 0),
          null,
        ),
        bold: const TextStyle(fontWeight: FontWeight.bold),
        subscript: const TextStyle(
          fontFeatures: [
            FontFeature.liningFigures(),
            FontFeature.subscripts(),
          ],
        ),
        superscript: const TextStyle(
          fontFeatures: [
            FontFeature.liningFigures(),
            FontFeature.superscripts(),
          ],
        ),
        italic: const TextStyle(fontStyle: FontStyle.italic),
        small: const TextStyle(fontSize: 12),
        underline: const TextStyle(decoration: TextDecoration.underline),
        strikeThrough: const TextStyle(decoration: TextDecoration.lineThrough),
        inlineCode: InlineCodeStyle(
          backgroundColor: Colors.grey.shade100,
          radius: const Radius.circular(3),
          style: inlineCodeStyle,
          header1: inlineCodeStyle.copyWith(
            fontSize: 32,
            fontWeight: FontWeight.w500,
          ),
          header2: inlineCodeStyle.copyWith(
            fontSize: 22,
            fontWeight: FontWeight.w500,
          ),
          header3: inlineCodeStyle.copyWith(
            fontSize: 18,
            fontWeight: FontWeight.w500,
          ),
        ),
        link: TextStyle(
          color: themeData.colorScheme.secondary,
          decoration: TextDecoration.underline,
        ),
        placeHolder: DefaultTextBlockStyle(
            defaultTextStyle.style.copyWith(
              fontSize: 20,
              height: 1.5,
              color: Colors.grey.withOpacity(0.6),
            ),
            const VerticalSpacing(0, 0),
            const VerticalSpacing(0, 0),
            null),
        lists: DefaultListBlockStyle(
          baseStyle,
          baseSpacing,
          const VerticalSpacing(0, 6),
          null,
          null,
        ),
        quote: DefaultTextBlockStyle(
          TextStyle(color: baseStyle.color!.withOpacity(0.6)),
          baseSpacing,
          const VerticalSpacing(6, 2),
          BoxDecoration(
            border: Border(
              left: BorderSide(width: 4, color: Colors.grey.shade300),
            ),
          ),
        ),
        code: DefaultTextBlockStyle(
            TextStyle(
              color: Colors.blue.shade900.withOpacity(0.9),
              fontFamily: fontFamily,
              fontSize: 13,
              height: 1.15,
            ),
            baseSpacing,
            const VerticalSpacing(0, 0),
            BoxDecoration(
              color: Colors.grey.shade50,
              borderRadius: BorderRadius.circular(2),
            )),
        indent: DefaultTextBlockStyle(
          baseStyle,
          baseSpacing,
          const VerticalSpacing(0, 6),
          null,
        ),
        align: DefaultTextBlockStyle(
          baseStyle,
          const VerticalSpacing(0, 0),
          const VerticalSpacing(0, 0),
          null,
        ),
        leading: DefaultTextBlockStyle(
          baseStyle,
          const VerticalSpacing(0, 0),
          const VerticalSpacing(0, 0),
          null,
        ),
        sizeSmall: const TextStyle(fontSize: 10),
        sizeLarge: const TextStyle(fontSize: 18),
        sizeHuge: const TextStyle(fontSize: 22));
  }

  DefaultStyles merge(DefaultStyles other) {
    return DefaultStyles(
      h1: other.h1 ?? h1,
      h2: other.h2 ?? h2,
      h3: other.h3 ?? h3,
      h4: other.h4 ?? h4,
      h5: other.h5 ?? h5,
      h6: other.h6 ?? h6,
      paragraph: other.paragraph ?? paragraph,
      bold: other.bold ?? bold,
      subscript: other.subscript ?? subscript,
      superscript: other.superscript ?? superscript,
      italic: other.italic ?? italic,
      small: other.small ?? small,
      underline: other.underline ?? underline,
      strikeThrough: other.strikeThrough ?? strikeThrough,
      inlineCode: other.inlineCode ?? inlineCode,
      link: other.link ?? link,
      color: other.color ?? color,
      placeHolder: other.placeHolder ?? placeHolder,
      lists: other.lists ?? lists,
      quote: other.quote ?? quote,
      code: other.code ?? code,
      indent: other.indent ?? indent,
      align: other.align ?? align,
      leading: other.leading ?? leading,
      sizeSmall: other.sizeSmall ?? sizeSmall,
      sizeLarge: other.sizeLarge ?? sizeLarge,
      sizeHuge: other.sizeHuge ?? sizeHuge,
    );
  }
}