/// inou Text Styles & Typography Widgets
/// 
/// RULES:
/// - Pages MUST use InouText.* styles or widgets
/// - NO raw TextStyle() in page code
/// - NO fontSize: or fontWeight: in page code
/// 
/// Usage:
///   Text('Hello', style: InouText.pageTitle)
///   InouText.pageTitle('Hello')
///   InouText.body('Paragraph', color: InouTheme.textMuted)

import 'package:flutter/material.dart';
import 'inou_theme.dart';

/// Typography system for inou
/// 
/// Base: 16px (1rem), Sora font, line-height 1.5
class InouText {
  InouText._();

  // ===========================================
  // FONT FAMILY
  // ===========================================
  static const String fontFamily = 'Sora';

  // ===========================================
  // TEXT STYLES
  // ===========================================

  /// Page title: 2.5rem (40px), weight 800 (ExtraBold)
  /// Use for: Main page headings like "Style Guide", "Privacy Policy"
  static const TextStyle pageTitle = TextStyle(
    fontFamily: fontFamily,
    fontSize: 40.0,  // 2.5 * 16
    fontWeight: FontWeight.w800,
    letterSpacing: -0.5,
    height: 1.2,
    color: InouTheme.text,
  );

  /// Hero title: 2.25rem (36px), weight 300 (Light)
  /// Use for: Large hero text like "Your data. Your rules."
  static const TextStyle heroTitle = TextStyle(
    fontFamily: fontFamily,
    fontSize: 36.0,  // 2.25 * 16
    fontWeight: FontWeight.w300,
    height: 1.2,
    letterSpacing: -1.08,  // -0.03em
    color: InouTheme.text,
  );

  /// Section title: 1.4rem (22.4px), weight 600 (SemiBold)
  /// Use for: Section headings like "What we collect"
  static const TextStyle sectionTitle = TextStyle(
    fontFamily: fontFamily,
    fontSize: 22.4,  // 1.4 * 16
    fontWeight: FontWeight.w600,
    color: InouTheme.text,
  );

  /// Subsection title: 1.1rem (17.6px), weight 600 (SemiBold)
  /// Use for: Subsection headings like "Account information"
  static const TextStyle subsectionTitle = TextStyle(
    fontFamily: fontFamily,
    fontSize: 17.6,  // 1.1 * 16
    fontWeight: FontWeight.w600,
    color: InouTheme.text,
  );

  /// H3: 1.125rem (18px), weight 500 (Medium)
  /// Use for: Tertiary headings
  static const TextStyle h3 = TextStyle(
    fontFamily: fontFamily,
    fontSize: 18.0,  // 1.125 * 16
    fontWeight: FontWeight.w500,
    color: InouTheme.text,
  );

  /// Intro text: 1.15rem (18.4px), weight 300 (Light)
  /// Use for: Introduction paragraphs, larger body text
  static const TextStyle intro = TextStyle(
    fontFamily: fontFamily,
    fontSize: 18.4,
    fontWeight: FontWeight.w300,
    height: 1.8,
    color: InouTheme.textMuted,
  );

  /// Body light: 1rem (16px), weight 300 (Light)
  /// Use for: Long-form content, articles, descriptions
  static const TextStyle bodyLight = TextStyle(
    fontFamily: fontFamily,
    fontSize: 16.0,
    fontWeight: FontWeight.w300,
    height: 1.5,
    color: InouTheme.text,
  );

  /// Body regular: 1rem (16px), weight 400 (Regular)
  /// Use for: UI labels, default text, buttons
  static const TextStyle body = TextStyle(
    fontFamily: fontFamily,
    fontSize: 16.0,
    fontWeight: FontWeight.w400,
    height: 1.5,
    color: InouTheme.text,
  );

  /// Body small: 0.85rem (13.6px), weight 400 (Regular)
  /// Use for: Secondary text, captions, helper text
  static const TextStyle bodySmall = TextStyle(
    fontFamily: fontFamily,
    fontSize: 13.6,  // 0.85 * 16
    fontWeight: FontWeight.w400,
    color: InouTheme.text,
  );

  /// Label: 1rem (16px), weight 500 (Medium)
  /// Use for: Form labels, button text
  static const TextStyle label = TextStyle(
    fontFamily: fontFamily,
    fontSize: 16.0,
    fontWeight: FontWeight.w500,
    color: InouTheme.text,
  );

  /// Label caps: 0.75rem (12px), weight 600, uppercase
  /// Use for: Category labels like "TEXT BLOCKS", "TYPOGRAPHY SCALE"
  static const TextStyle labelCaps = TextStyle(
    fontFamily: fontFamily,
    fontSize: 12.0,  // 0.75 * 16
    fontWeight: FontWeight.w600,
    letterSpacing: 1.2,  // 0.1em
    color: InouTheme.textSubtle,
  );

  /// Logo: 1.75rem (28px), weight 700 (Bold)
  /// Use for: "inou" in header
  static const TextStyle logo = TextStyle(
    fontFamily: fontFamily,
    fontSize: 28.0,  // 1.75 * 16
    fontWeight: FontWeight.w700,
    letterSpacing: -0.56,  // -0.02em
  );

  /// Logo light: 1.75rem (28px), weight 300 (Light)
  /// Use for: "health" in header
  static const TextStyle logoLight = TextStyle(
    fontFamily: fontFamily,
    fontSize: 28.0,  // 1.75 * 16
    fontWeight: FontWeight.w300,
    letterSpacing: -0.56,  // -0.02em
  );

  /// Logo tagline: 0.95rem (15.2px), weight 300 (Light)
  /// Use for: "ai answers for you" tagline
  static const TextStyle logoTagline = TextStyle(
    fontFamily: fontFamily,
    fontSize: 15.2,  // 0.95 * 16
    fontWeight: FontWeight.w300,
    letterSpacing: 0.608,  // 0.04em
    color: InouTheme.textMuted,
  );

  /// Nav item: 1rem (16px), weight 400 (Regular)
  /// Use for: Navigation menu items
  static const TextStyle nav = TextStyle(
    fontFamily: fontFamily,
    fontSize: 16.0,
    fontWeight: FontWeight.w400,
    color: InouTheme.text,
  );

  /// Nav item active: 1rem (16px), weight 600 (SemiBold)
  /// Use for: Active navigation menu items
  static const TextStyle navActive = TextStyle(
    fontFamily: fontFamily,
    fontSize: 16.0,
    fontWeight: FontWeight.w600,
    color: InouTheme.accent,
  );

  /// Mono: SF Mono, 0.85rem (13.6px)
  /// Use for: Code, technical data, IDs
  static const TextStyle mono = TextStyle(
    fontFamily: 'SF Mono',
    fontFamilyFallback: ['Monaco', 'Consolas', 'monospace'],
    fontSize: 13.6,  // 0.85 * 16
    fontWeight: FontWeight.w400,
    color: InouTheme.text,
  );

  /// Profile name: 1.25rem (20px), weight 600 (SemiBold)
  /// Use for: User names in profile cards
  static const TextStyle profileName = TextStyle(
    fontFamily: fontFamily,
    fontSize: 20.0,  // 1.25 * 16
    fontWeight: FontWeight.w600,
    color: InouTheme.text,
  );

  /// Badge: 1rem (16px), weight 500 (Medium)
  /// Use for: Badge/pill text
  static const TextStyle badge = TextStyle(
    fontFamily: fontFamily,
    fontSize: 16.0,
    fontWeight: FontWeight.w500,
  );

  /// Button: 1rem (16px), weight 500 (Medium)
  /// Use for: Button text
  static const TextStyle button = TextStyle(
    fontFamily: fontFamily,
    fontSize: 16.0,
    fontWeight: FontWeight.w500,
  );

  /// Input: 1rem (16px), weight 400 (Regular)
  /// Use for: Text input fields
  static const TextStyle input = TextStyle(
    fontFamily: fontFamily,
    fontSize: 16.0,
    fontWeight: FontWeight.w400,
    color: InouTheme.text,
  );

  /// Input placeholder: 1rem (16px), weight 400 (Regular)
  /// Use for: Placeholder text in inputs
  static const TextStyle inputPlaceholder = TextStyle(
    fontFamily: fontFamily,
    fontSize: 16.0,
    fontWeight: FontWeight.w400,
    color: InouTheme.textSubtle,
  );

  /// Error text: 0.85rem (13.6px), weight 400 (Regular)
  /// Use for: Form validation errors
  static const TextStyle error = TextStyle(
    fontFamily: fontFamily,
    fontSize: 13.6,
    fontWeight: FontWeight.w400,
    color: InouTheme.danger,
  );

  /// Link: inherits size, weight 400, accent color
  /// Use for: Inline links
  static TextStyle link({double? fontSize}) => TextStyle(
    fontFamily: fontFamily,
    fontSize: fontSize ?? 16.0,
    fontWeight: FontWeight.w400,
    color: InouTheme.accent,
    decoration: TextDecoration.underline,
    decorationColor: InouTheme.accent,
  );

  // ===========================================
  // CONVENIENCE WIDGETS
  // ===========================================

  /// Page title widget
  static Widget pageTitleText(
    String text, {
    Color? color,
    TextAlign? textAlign,
  }) {
    return Text(
      text,
      style: pageTitle.copyWith(color: color),
      textAlign: textAlign,
    );
  }

  /// Hero title widget
  static Widget heroTitleText(
    String text, {
    Color? color,
    TextAlign? textAlign,
  }) {
    return Text(
      text,
      style: heroTitle.copyWith(color: color),
      textAlign: textAlign,
    );
  }

  /// Section title widget
  static Widget sectionTitleText(
    String text, {
    Color? color,
    TextAlign? textAlign,
  }) {
    return Text(
      text,
      style: sectionTitle.copyWith(color: color),
      textAlign: textAlign,
    );
  }

  /// Subsection title widget
  static Widget subsectionTitleText(
    String text, {
    Color? color,
    TextAlign? textAlign,
  }) {
    return Text(
      text,
      style: subsectionTitle.copyWith(color: color),
      textAlign: textAlign,
    );
  }

  /// Body text widget
  static Widget bodyText(
    String text, {
    Color? color,
    TextAlign? textAlign,
    int? maxLines,
    TextOverflow? overflow,
  }) {
    return Text(
      text,
      style: body.copyWith(color: color),
      textAlign: textAlign,
      maxLines: maxLines,
      overflow: overflow,
    );
  }

  /// Body light text widget (for long-form)
  static Widget bodyLightText(
    String text, {
    Color? color,
    TextAlign? textAlign,
  }) {
    return Text(
      text,
      style: bodyLight.copyWith(color: color),
      textAlign: textAlign,
    );
  }

  /// Intro text widget
  static Widget introText(
    String text, {
    Color? color,
    TextAlign? textAlign,
  }) {
    return Text(
      text,
      style: intro.copyWith(color: color),
      textAlign: textAlign,
    );
  }

  /// Label caps widget (auto-uppercases)
  static Widget labelCapsText(
    String text, {
    Color? color,
    TextAlign? textAlign,
  }) {
    return Text(
      text.toUpperCase(),
      style: labelCaps.copyWith(color: color),
      textAlign: textAlign,
    );
  }

  /// Mono text widget
  static Widget monoText(
    String text, {
    Color? color,
    TextAlign? textAlign,
  }) {
    return Text(
      text,
      style: mono.copyWith(color: color),
      textAlign: textAlign,
    );
  }

  /// Small text widget
  static Widget smallText(
    String text, {
    Color? color,
    TextAlign? textAlign,
  }) {
    return Text(
      text,
      style: bodySmall.copyWith(color: color),
      textAlign: textAlign,
    );
  }

  /// Error text widget
  static Widget errorText(
    String text, {
    TextAlign? textAlign,
  }) {
    return Text(
      text,
      style: error,
      textAlign: textAlign,
    );
  }

  // ===========================================
  // RICH TEXT HELPERS
  // ===========================================

  /// Build rich text with multiple styled spans
  static Widget rich(
    List<InlineSpan> children, {
    TextAlign? textAlign,
  }) {
    return Text.rich(
      TextSpan(children: children),
      textAlign: textAlign,
    );
  }
}

/// Styled text spans for use with InouText.rich()
class InouSpan {
  InouSpan._();

  /// Accent colored text
  static TextSpan accent(String text, {TextStyle? baseStyle}) {
    return TextSpan(
      text: text,
      style: (baseStyle ?? InouText.body).copyWith(color: InouTheme.accent),
    );
  }

  /// Muted colored text
  static TextSpan muted(String text, {TextStyle? baseStyle}) {
    return TextSpan(
      text: text,
      style: (baseStyle ?? InouText.body).copyWith(color: InouTheme.textMuted),
    );
  }

  /// Subtle colored text
  static TextSpan subtle(String text, {TextStyle? baseStyle}) {
    return TextSpan(
      text: text,
      style: (baseStyle ?? InouText.body).copyWith(color: InouTheme.textSubtle),
    );
  }

  /// Bold text
  static TextSpan bold(String text, {TextStyle? baseStyle}) {
    return TextSpan(
      text: text,
      style: (baseStyle ?? InouText.body).copyWith(fontWeight: FontWeight.w700),
    );
  }

  /// SemiBold text
  static TextSpan semiBold(String text, {TextStyle? baseStyle}) {
    return TextSpan(
      text: text,
      style: (baseStyle ?? InouText.body).copyWith(fontWeight: FontWeight.w600),
    );
  }

  /// Light text
  static TextSpan light(String text, {TextStyle? baseStyle}) {
    return TextSpan(
      text: text,
      style: (baseStyle ?? InouText.body).copyWith(fontWeight: FontWeight.w300),
    );
  }

  /// Plain text (default style)
  static TextSpan plain(String text, {TextStyle? style}) {
    return TextSpan(text: text, style: style);
  }

  /// Link text
  static TextSpan link(
    String text, {
    VoidCallback? onTap,
    TextStyle? baseStyle,
  }) {
    return TextSpan(
      text: text,
      style: (baseStyle ?? InouText.body).copyWith(
        color: InouTheme.accent,
        decoration: TextDecoration.underline,
        decorationColor: InouTheme.accent,
      ),
      // Note: For tap handling, wrap in GestureDetector or use url_launcher
    );
  }
}