import { Platform } from "react-native";
import { darkHighlightColors, lightHighlightColors } from "@getpaseo/highlight";

export const baseColors = {
  // Base colors
  white: "#ffffff",
  black: "#000000",

  // Zinc scale (primary gray palette)
  zinc: {
    50: "#fafafa",
    100: "#f4f4f5",
    200: "#e4e4e7",
    300: "#d4d4d8",
    400: "#a1a1aa",
    500: "#71717a",
    600: "#52525b",
    700: "#3f3f46",
    800: "#27272a",
    850: "#1a1a1d",
    900: "#18181b",
    950: "#121214",
  },

  // Gray scale
  gray: {
    50: "#f9fafb",
    100: "#f3f4f6",
    200: "#e5e7eb",
    300: "#d1d5db",
    400: "#9ca3af",
    500: "#6b7280",
    600: "#4b5563",
    700: "#374151",
    800: "#1f2937",
    900: "#111827",
  },

  // Slate scale
  slate: {
    200: "#e2e8f0",
  },

  // Blue scale
  blue: {
    50: "#eff6ff",
    100: "#dbeafe",
    200: "#bfdbfe",
    300: "#93c5fd",
    400: "#60a5fa",
    500: "#3b82f6",
    600: "#2563eb",
    700: "#1d4ed8",
    800: "#1e40af",
    900: "#1e3a8a",
    950: "#172554",
  },

  // Green scale
  green: {
    100: "#dcfce7",
    200: "#bbf7d0",
    400: "#4ade80",
    500: "#22c55e",
    600: "#16a34a",
    800: "#166534",
    900: "#14532d",
  },

  // Red scale
  red: {
    100: "#fee2e2",
    200: "#fecaca",
    300: "#fca5a5",
    500: "#ef4444",
    600: "#dc2626",
    800: "#991b1b",
    900: "#7f1d1d",
  },

  // Teal scale
  teal: {
    200: "#99f6e4",
  },

  // Amber scale
  amber: {
    500: "#f59e0b",
    700: "#b45309",
  },

  // Yellow scale
  yellow: {
    400: "#fbbf24",
  },

  // Purple scale
  purple: {
    500: "#a855f7",
    600: "#9333ea",
  },

  // Orange scale
  orange: {
    500: "#f97316",
    600: "#ea580c",
  },
} as const;

export type ThemeName = "light" | "dark" | "zinc" | "midnight" | "claude" | "ghostty";

// Diff colors — the +/- inside a diff view, where the color *is* the signal and has to
// survive being scanned line by line, so it stays saturated. Light uses muted tones, dark
// uses the brighter palette values.
//
// A diff *stat* — the "+12 −3" footnote next to a title — is not this. It reads as one of
// several muted signals in a row, so it uses statusMutedSuccess/Danger below rather than a
// near-duplicate tier of its own.
const lightDiffColors = {
  diffAddition: "#15803d", // green-700 — readable on white without screaming
  diffDeletion: "#b91c1c", // red-700
};

const darkDiffColors = {
  diffAddition: "#4ade80", // green-400
  diffDeletion: "#ef4444", // red-500
};

// Status colors — semantic signals for success/danger/warning/merged. Used by check
// statuses, PR states, and review decisions.
//
// Normalized, not hand-picked. Every color below shares one lightness and one chroma within
// its tier; only the hue changes, and each hue is the one that family already had. Chroma is
// a fixed fraction of what sRGB allows at that lightness and hue, because the gamut is
// lopsided — amber runs out of room long before red does, so a literal equal-chroma set
// leaves amber flat and red screaming. Equal fractions is what makes four hues read as one
// family. Regenerate with the same rule rather than nudging one value.
//
// Two tiers. Full is for a surface whose job is to report the status — the PR pane, a usage
// bar. Muted is for the same signal repeated on every row of a dense list, where full
// saturation makes the list itself the loudest thing on screen; it sits at roughly
// foregroundMuted's weight so a row built from it reads as one line of subtitle.
//
// Deliberately not on this scale: the workspace status dot. That one is supposed to shout,
// so it keeps the raw palette — see getStatusDotColor.
const lightStatusColors = {
  // L=0.53, chroma 90% of gamut max
  statusSuccess: "#1f8040",
  statusDanger: "#c32424",
  statusWarning: "#91601b",
  statusMerged: "#8728e5",
  // L=0.50, chroma 45% of gamut max
  statusMutedSuccess: "#496d50",
  statusMutedDanger: "#904d46",
  statusMutedWarning: "#755f45",
  statusMutedMerged: "#6e519d",
};

const darkStatusColors = {
  // L=0.66, chroma 90% of gamut max
  statusSuccess: "#2ead58",
  statusDanger: "#f65048",
  statusWarning: "#c38328",
  statusMerged: "#a670f5",
  // L=0.70, chroma 40% of gamut max
  statusMutedSuccess: "#7cac85",
  statusMutedDanger: "#ca8c85",
  statusMutedWarning: "#b79875",
  statusMutedMerged: "#a594c6",
};

// Semantic color tokens - Layer-based system
const lightSemanticColors = {
  // Surfaces (layers) - shifted one step lighter
  surface0: "#ffffff", // App background
  surface1: "#fafafa", // Subtle hover (was zinc-100, now zinc-50)
  surface2: "#f4f4f5", // Elevated: badges, inputs, sheets (was zinc-200, now zinc-100)
  surface3: "#e4e4e7", // Highest elevation (was zinc-300, now zinc-200)
  surface4: "#d4d4d8", // Extra emphasis (was zinc-400, now zinc-300)
  surfaceDiffEmpty: "#f6f6f6", // Empty side of split diff rows, between surface1 and surface2 and biased toward surface2
  surfaceSidebar: "#f4f4f5", // Sidebar background (darker than main)
  surfaceSidebarHover: "#e9e9ec", // Sidebar hover (darker in light mode)
  surfaceWorkspace: "#ffffff", // Workspace main background

  // Text
  foreground: "#1a1a1e",
  foregroundMuted: "#71717a",
  foregroundExtraMuted: "#a1a1aa",

  // Controls
  scrollbarHandle: "#3f3f46", // zinc-700

  // Borders - shifted one step lighter
  border: "#e4e4e7", // (was zinc-200, now zinc-200 - keep for contrast)
  borderAccent: "#ececf1", // Softer accent border for low-emphasis outlines

  // Brand
  accent: "#20744A",
  accentBright: "#239956",
  accentForeground: "#ffffff",

  // Semantic
  destructive: "#b04138", // dark warm red on white — calm but unambiguously red
  destructiveForeground: "#ffffff",
  success: "#20744A",
  successForeground: "#ffffff",

  // Legacy aliases (for gradual migration)
  background: "#ffffff",
  popover: "#ffffff",
  popoverForeground: "#1a1a1e",
  primary: "#18181b",
  primaryForeground: "#fafafa",
  secondary: "#f4f4f5",
  secondaryForeground: "#1a1a1e",
  muted: "#f4f4f5",
  mutedForeground: "#71717a",
  accentBorder: "#ececf1",
  input: "#f4f4f5",
  ring: "#18181b",

  ...lightDiffColors,
  ...lightStatusColors,

  terminal: {
    background: "#ffffff",
    foreground: "#1a1a1e",
    cursor: "#1a1a1e",
    cursorAccent: "#ffffff",
    selectionBackground: "rgba(0, 0, 0, 0.15)",
    selectionForeground: "#1a1a1e",

    black: "#1a1a1e",
    red: "#dc2626",
    green: "#16a34a",
    yellow: "#ca8a04",
    blue: "#2563eb",
    magenta: "#9333ea",
    cyan: "#0891b2",
    white: "#ffffff",

    brightBlack: "#3f3f46",
    brightRed: "#ef4444",
    brightGreen: "#22c55e",
    brightYellow: "#f59e0b",
    brightBlue: "#3b82f6",
    brightMagenta: "#a855f7",
    brightCyan: "#06b6d4",
    brightWhite: "#fafafa",
  },
} as const;

// ---------------------------------------------------------------------------
// Dark theme variant builder
// ---------------------------------------------------------------------------

interface DarkThemeConfig {
  surface0: string;
  surface1: string;
  surface2: string;
  surface3: string;
  surface4: string;
  surfaceDiffEmpty: string;
  surfaceSidebar: string;
  surfaceSidebarHover: string;
  foregroundMuted: string;
  foregroundExtraMuted: string;
  scrollbarHandle: string;
  border: string;
  borderAccent: string;
  accent: string;
  accentBright: string;
  accentForeground?: string;
  destructive: string;
}

const darkTerminalAnsi = {
  red: "#e07070",
  green: "#5dba80",
  yellow: "#d4a44a",
  blue: "#6a9de0",
  magenta: "#b07ad0",
  cyan: "#4aabb8",
  white: "#d4d4d8",
  brightRed: "#e89090",
  brightGreen: "#7ecf9a",
  brightYellow: "#e0be6e",
  brightBlue: "#8ab4e8",
  brightMagenta: "#c49ae0",
  brightCyan: "#6ec2cc",
  brightWhite: "#f0f0f2",
} as const;

function buildDarkSemanticColors(tint: DarkThemeConfig) {
  return {
    surface0: tint.surface0,
    surface1: tint.surface1,
    surface2: tint.surface2,
    surface3: tint.surface3,
    surface4: tint.surface4,
    surfaceDiffEmpty: tint.surfaceDiffEmpty,
    surfaceSidebar: tint.surfaceSidebar,
    surfaceSidebarHover: tint.surfaceSidebarHover,
    surfaceWorkspace: tint.surface1,

    foreground: "#fafafa",
    foregroundMuted: tint.foregroundMuted,
    foregroundExtraMuted: tint.foregroundExtraMuted,

    scrollbarHandle: tint.scrollbarHandle,

    border: tint.border,
    borderAccent: tint.borderAccent,

    accent: tint.accent,
    accentBright: tint.accentBright,
    accentForeground: tint.accentForeground ?? "#ffffff",

    destructive: tint.destructive,
    destructiveForeground: "#ffffff",
    success: tint.accent,
    successForeground: "#ffffff",

    // Legacy aliases (for gradual migration)
    background: tint.surface0,
    popover: tint.surface2,
    popoverForeground: "#fafafa",
    primary: "#fafafa",
    primaryForeground: tint.surface0,
    secondary: tint.surface2,
    secondaryForeground: "#fafafa",
    muted: tint.surface2,
    mutedForeground: tint.foregroundMuted,
    accentBorder: tint.borderAccent,
    input: tint.surface2,
    ring: "#d4d4d8",

    ...darkDiffColors,
    ...darkStatusColors,

    terminal: {
      background: tint.surface0,
      foreground: "#fafafa",
      cursor: "#fafafa",
      cursorAccent: tint.surface0,
      selectionBackground: "rgba(255, 255, 255, 0.2)",
      selectionForeground: "#fafafa",
      black: tint.surfaceSidebar,
      ...darkTerminalAnsi,
      brightBlack: tint.surface3,
    },
  };
}

// ---------------------------------------------------------------------------
// Dark tint definitions
// ---------------------------------------------------------------------------

// Paseo — subtle teal-green tint (default)
const paseoDarkColors = buildDarkSemanticColors({
  surface0: "#181B1A",
  surface1: "#1E2120",
  surface2: "#272A29",
  surface3: "#434645",
  surface4: "#595B5B",
  surfaceDiffEmpty: "#252827",
  surfaceSidebar: "#141716",
  surfaceSidebarHover: "#1c1f1e",
  foregroundMuted: "#A1A5A4",
  foregroundExtraMuted: "#717574",
  scrollbarHandle: "#717574",
  border: "#252B2A",
  borderAccent: "#2F3534",
  accent: "#20744A",
  accentBright: "#7ccba0",
  destructive: "#c64f43", // warm red, hue ~7 — reads as red (not pink) against the green tint
});

// Zinc — neutral gray, no tint
const zincDarkColors = buildDarkSemanticColors({
  surface0: "#18181b",
  surface1: "#1f1f22",
  surface2: "#27272a",
  surface3: "#3f3f46",
  surface4: "#52525b",
  surfaceDiffEmpty: "#242427",
  surfaceSidebar: "#131316",
  surfaceSidebarHover: "#1b1b1e",
  foregroundMuted: "#a1a1aa",
  foregroundExtraMuted: "#71717a",
  scrollbarHandle: "#71717a",
  border: "#27272a",
  borderAccent: "#303036",
  accent: "#e4e4e7",
  accentBright: "#fafafa",
  accentForeground: "#18181b", // monochrome zinc accent is near-white — needs dark text
  destructive: "#c44a4a", // neutral red, hue 0 — clearly red without screaming
});

// Midnight — subtle blue tint
const midnightDarkColors = buildDarkSemanticColors({
  surface0: "#161820",
  surface1: "#1c1e27",
  surface2: "#252731",
  surface3: "#3c3e4c",
  surface4: "#535564",
  surfaceDiffEmpty: "#222430",
  surfaceSidebar: "#121420",
  surfaceSidebarHover: "#1a1c28",
  foregroundMuted: "#9a9db0",
  foregroundExtraMuted: "#6b6e82",
  scrollbarHandle: "#6b6e82",
  border: "#242636",
  borderAccent: "#2e3040",
  accent: "#3b6fcf",
  accentBright: "#7eaaeb",
  destructive: "#c44a52", // red with a hint of cool lean against the blue tint
});

// Claude — warm neutral with subtle orange undertone
const claudeDarkColors = buildDarkSemanticColors({
  surface0: "#1f1f1e",
  surface1: "#262523",
  surface2: "#2f2d2b",
  surface3: "#4a4745",
  surface4: "#605d5b",
  surfaceDiffEmpty: "#2a2826",
  surfaceSidebar: "#1a1918",
  surfaceSidebarHover: "#222120",
  foregroundMuted: "#ada9a5",
  foregroundExtraMuted: "#78746f",
  scrollbarHandle: "#78746f",
  border: "#2c2a27",
  borderAccent: "#36332f",
  accent: "#d97757",
  accentBright: "#e89a7f",
  destructive: "#cf513e", // warm orange-red, hue ~10 — sits with the Claude orange accent
});

// Ghostty — blue-tinted dark based on Ghostty default background
const ghosttyDarkColors = buildDarkSemanticColors({
  surface0: "#282c34",
  surface1: "#2f333d",
  surface2: "#383c48",
  surface3: "#4a4f5e",
  surface4: "#5b6175",
  surfaceDiffEmpty: "#323643",
  surfaceSidebar: "#21252d",
  surfaceSidebarHover: "#292d36",
  foregroundMuted: "#c8ccd8",
  foregroundExtraMuted: "#a0a4b2",
  scrollbarHandle: "#a0a4b2",
  border: "#353a47",
  borderAccent: "#3f4454",
  accent: "#89b4fa",
  accentBright: "#b4d0fc",
  destructive: "#c44a55", // red with slight cool lean against the slate-blue surfaces
});

export const SPACING = {
  0: 0,
  1: 4,
  1.5: 6,
  2: 8,
  3: 12,
  4: 16,
  6: 24,
  8: 32,
  12: 48,
  16: 64,
  20: 80,
  24: 96,
  32: 128,
} as const;

export const FONT_SIZE = {
  xs: 12,
  code: 12,
  sm: 14,
  base: 16,
  lg: 18,
  xl: 20,
  "2xl": 22,
  "3xl": 26,
  "4xl": 34,
} as const;

export const LINE_HEIGHT = {
  diff: 22,
} as const;

export const ICON_SIZE = {
  xs: 12,
  sm: 14,
  md: 16,
  lg: 20,
} as const;

export const FONT_WEIGHT = {
  normal: "normal" as const,
  medium: "500" as const,
  semibold: "600" as const,
  bold: "bold" as const,
} as const;

export const BORDER_RADIUS = {
  none: 0,
  sm: 2,
  base: 4,
  md: 6,
  lg: 8,
  xl: 12,
  "2xl": 16,
  full: 9999,
} as const;

export const BORDER_WIDTH = {
  0: 0,
  1: 1,
  2: 2,
} as const;

export const OPACITY = {
  0: 0,
  50: 0.5,
  100: 1,
} as const;

// Platform default font stacks — copied verbatim from constants/theme.ts `Fonts`
// (sans -> ui, mono -> mono). These seed the dynamic `fontFamily` theme token and
// are the fallback an empty user-supplied family resolves to at apply time.
export const DEFAULT_UI_FONT_STACK: string = Platform.select({
  ios: "system-ui",
  default: "normal",
  web: "system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif",
});

export const DEFAULT_MONO_FONT_STACK: string = Platform.select({
  ios: "ui-monospace",
  default: "monospace",
  web: "SFMono-Regular, Menlo, Monaco, Consolas, 'Liberation Mono', 'Courier New', monospace",
});

// `fontSize`, `fontFamily`, and `lineHeight` are deliberately widened to plain
// `number`/`string` (not narrowed by `as const`) so the appearance updater can patch
// them at runtime via `UnistylesRuntime.updateTheme`. The remaining tokens keep their
// literal types.
interface CommonTheme {
  spacing: typeof SPACING;
  fontSize: Record<keyof typeof FONT_SIZE, number>;
  fontFamily: { ui: string; mono: string };
  lineHeight: Record<keyof typeof LINE_HEIGHT, number>;
  iconSize: typeof ICON_SIZE;
  fontWeight: typeof FONT_WEIGHT;
  borderRadius: typeof BORDER_RADIUS;
  borderWidth: typeof BORDER_WIDTH;
  opacity: typeof OPACITY;
}

const commonTheme: CommonTheme = {
  spacing: SPACING,
  fontSize: FONT_SIZE,
  fontFamily: { ui: DEFAULT_UI_FONT_STACK, mono: DEFAULT_MONO_FONT_STACK },
  lineHeight: LINE_HEIGHT,
  iconSize: ICON_SIZE,
  fontWeight: FONT_WEIGHT,
  borderRadius: BORDER_RADIUS,
  borderWidth: BORDER_WIDTH,
  opacity: OPACITY,
};

const darkShadow = {
  sm: {
    shadowColor: "rgba(0, 0, 0, 0.25)",
    shadowOffset: { width: 0, height: 2 },
    shadowRadius: 4,
    elevation: 2,
  },
  md: {
    shadowColor: "rgba(0, 0, 0, 0.20)",
    shadowOffset: { width: 0, height: 4 },
    shadowRadius: 8,
    elevation: 8,
  },
  lg: {
    shadowColor: "rgba(0, 0, 0, 0.40)",
    shadowOffset: { width: 0, height: 12 },
    shadowRadius: 24,
    elevation: 8,
  },
} as const;

function buildDarkTheme(semanticColors: ReturnType<typeof buildDarkSemanticColors>) {
  return {
    colorScheme: "dark" as const,
    colors: {
      ...semanticColors,
      palette: baseColors,
      syntax: darkHighlightColors,
    },
    shadow: darkShadow,
    ...commonTheme,
  } as const;
}

export const darkTheme = buildDarkTheme(paseoDarkColors);
export const darkZincTheme = buildDarkTheme(zincDarkColors);
export const darkMidnightTheme = buildDarkTheme(midnightDarkColors);
export const darkClaudeTheme = buildDarkTheme(claudeDarkColors);
export const darkGhosttyTheme = buildDarkTheme(ghosttyDarkColors);

export const lightTheme = {
  colorScheme: "light" as const,
  colors: {
    ...lightSemanticColors,
    palette: baseColors,
    syntax: lightHighlightColors,
  },
  shadow: {
    sm: {
      shadowColor: "rgba(0, 0, 0, 0.02)",
      shadowOffset: { width: 0, height: 2 },
      shadowRadius: 8,
      elevation: 2,
    },
    md: {
      shadowColor: "rgba(0, 0, 0, 0.04)",
      shadowOffset: { width: 0, height: 4 },
      shadowRadius: 16,
      elevation: 4,
    },
    lg: {
      shadowColor: "rgba(0, 0, 0, 0.08)",
      shadowOffset: { width: 0, height: 8 },
      shadowRadius: 24,
      elevation: 8,
    },
  },
  ...commonTheme,
} as const;

// Keep compatibility with existing code
export const theme = darkTheme;

// Export a union type that works for both themes
export type Theme = typeof darkTheme | typeof lightTheme;

type UnistylesThemeKey =
  | "light"
  | "dark"
  | "darkZinc"
  | "darkMidnight"
  | "darkClaude"
  | "darkGhostty";

export const THEME_TO_UNISTYLES: Record<ThemeName, UnistylesThemeKey> = {
  light: "light",
  dark: "dark",
  zinc: "darkZinc",
  midnight: "darkMidnight",
  claude: "darkClaude",
  ghostty: "darkGhostty",
};

export const THEME_SWATCHES: Record<ThemeName, string> = {
  light: "#ffffff",
  dark: "#2D8B62",
  zinc: "#808080",
  midnight: "#4A6BA8",
  claude: "#D97757",
  ghostty: "#8caaee",
};