import {
  type FontFamilyId,
  type IconPosition,
  type MindMapNode,
  type NodeShape,
  type ShadowStyle,
  type TextAlign,
  type VerticalAlign,
} from '@/types/map';
import { type MapTheme, paletteForDepth, themeMetrics } from '@/features/editor/themes';

/**
 * Fusion theme + personnalisations explicites du noeud.
 *
 * Regle unique : un champ absent du noeud herite du theme. Rien n'est jamais
 * ecrit dans le document pour "materialiser" un defaut, ce qui garantit que les
 * cartes v1 deja stockees restent lisibles et que changer de theme n'ecrase
 * aucune personnalisation.
 */

export const FONT_FAMILIES: Record<Exclude<FontFamilyId, 'theme'>, string> = {
  sans: "Inter, ui-sans-serif, system-ui, 'Segoe UI', Roboto, Arial, sans-serif",
  serif: "Georgia, 'Times New Roman', Times, serif",
  mono: "ui-monospace, SFMono-Regular, 'JetBrains Mono', Menlo, Consolas, monospace",
  rounded: "'Segoe UI', 'Trebuchet MS', ui-rounded, system-ui, sans-serif",
};

export const FONT_FAMILY_OPTIONS: Array<{ id: FontFamilyId; label: string }> = [
  { id: 'theme', label: 'Theme' },
  { id: 'sans', label: 'Sans-serif' },
  { id: 'serif', label: 'Serif' },
  { id: 'mono', label: 'Monospace' },
  { id: 'rounded', label: 'Arrondie' },
];

export const SHADOW_OPTIONS: Array<{ id: ShadowStyle; label: string }> = [
  { id: 'theme', label: 'Theme' },
  { id: 'none', label: 'Aucune' },
  { id: 'soft', label: 'Douce' },
  { id: 'strong', label: 'Marquee' },
];

const SHADOWS: Record<Exclude<ShadowStyle, 'theme'>, string> = {
  none: 'none',
  soft: '0 1px 2px rgba(15,23,42,0.06), 0 6px 16px -10px rgba(15,23,42,0.35)',
  strong: '0 2px 4px rgba(15,23,42,0.10), 0 14px 28px -12px rgba(15,23,42,0.55)',
};

/** Bornes appliquees a toute saisie utilisateur. */
export const LAYOUT_LIMITS = {
  width: { min: 60, max: 900 },
  height: { min: 32, max: 900 },
  paddingX: { min: 0, max: 64 },
  paddingY: { min: 0, max: 48 },
  maxTextWidth: { min: 80, max: 900 },
  fontSize: { min: 10, max: 48 },
  lineHeight: { min: 1, max: 2.4 },
  iconSize: { min: 12, max: 48 },
  iconGap: { min: 0, max: 32 },
  branchWidth: { min: 1, max: 10 },
} as const;

export function clampTo(value: number, bounds: { min: number; max: number }): number {
  return Math.min(bounds.max, Math.max(bounds.min, Math.round(value)));
}

/** Apparence entierement resolue d'un noeud, prete a etre appliquee en CSS. */
export interface NodeAppearance {
  background: string;
  color: string;
  borderColor: string;
  borderWidth: number;
  borderRadius: string;
  shape: NodeShape;
  circle: boolean;
  boxShadow: string;

  fontFamily: string;
  fontSize: number;
  fontWeight: number;
  fontStyle: 'normal' | 'italic';
  lineHeight: number;
  textAlign: TextAlign;
  verticalAlign: VerticalAlign;

  paddingX: number;
  paddingY: number;
  wrap: boolean;
  widthMode: 'auto' | 'fixed';
  heightMode: 'auto' | 'fixed';
  width?: number;
  height?: number;
  maxTextWidth: number;
  minWidth: number;
  minHeight: number;

  iconSize: number;
  iconGap: number;
  iconPosition: IconPosition;
}

function radiusForShape(shape: NodeShape, themeRadius: number): string {
  switch (shape) {
    case 'rectangle':
      return '3px';
    case 'capsule':
      return '999px';
    case 'circle':
      return '50%';
    case 'rounded':
    default:
      return `${themeRadius}px`;
  }
}

export function resolveNodeAppearance(
  node: MindMapNode,
  depth: number,
  theme: MapTheme,
): NodeAppearance {
  const palette = paletteForDepth(theme, depth);
  const metrics = themeMetrics(theme);
  const style = node.style ?? {};
  const layout = node.layout ?? {};
  const iconStyle = node.iconStyle ?? {};

  const shape = style.shape ?? theme.nodeShape;
  const fontFamily =
    style.fontFamily && style.fontFamily !== 'theme'
      ? FONT_FAMILIES[style.fontFamily]
      : theme.fontFamily;
  const shadow = style.shadow && style.shadow !== 'theme' ? SHADOWS[style.shadow] : theme.shadow;

  // `style.width` est l'ancien champ v1 : il vaut largeur fixe.
  const legacyWidth = style.width;
  const widthMode = layout.widthMode ?? (layout.width ?? legacyWidth ? 'fixed' : 'auto');
  const width = layout.width ?? legacyWidth;
  const heightMode = layout.heightMode ?? (layout.height ? 'fixed' : 'auto');

  return {
    background: style.backgroundColor ?? palette.background,
    color: style.textColor ?? palette.text,
    borderColor: style.borderColor ?? palette.border,
    borderWidth: theme.borderWidth,
    borderRadius: radiusForShape(shape, theme.nodeRadius),
    shape,
    circle: shape === 'circle',
    boxShadow: shadow,

    fontFamily,
    fontSize: style.fontSize ?? (depth === 0 ? 16 : 14),
    fontWeight: style.bold ? 700 : depth === 0 ? 600 : 500,
    fontStyle: style.italic ? 'italic' : 'normal',
    lineHeight: style.lineHeight ?? metrics.lineHeight,
    textAlign: style.textAlign ?? 'left',
    verticalAlign: style.verticalAlign ?? 'top',

    paddingX: layout.paddingX ?? metrics.paddingX,
    paddingY: layout.paddingY ?? metrics.paddingY,
    wrap: layout.wrap ?? true,
    widthMode: widthMode === 'fixed' && width ? 'fixed' : 'auto',
    heightMode: heightMode === 'fixed' && layout.height ? 'fixed' : 'auto',
    ...(width ? { width } : {}),
    ...(layout.height ? { height: layout.height } : {}),
    maxTextWidth: layout.maxTextWidth ?? metrics.maxTextWidth,
    minWidth: metrics.minNodeWidth,
    minHeight: metrics.minNodeHeight,

    iconSize: iconStyle.size ?? metrics.iconSize,
    iconGap: iconStyle.gap ?? metrics.iconGap,
    iconPosition: iconStyle.position ?? 'left',
  };
}

/** Style effectif de la branche entrante d'un noeud. */
export function resolveBranchAppearance(
  node: MindMapNode,
  theme: MapTheme,
  fallbackStyle: MindMapNode['branch'],
): { style: NonNullable<MindMapNode['branch']>['style']; width: number; color: string } {
  const branch = node.branch ?? {};
  return {
    style: branch.style ?? fallbackStyle?.style,
    width: branch.width ?? theme.branchWidth,
    color: branch.color ?? theme.branchColor,
  };
}