2 files changed, 185 insertions, 0 deletions
diff --git a/apps/web/src/constants/font-constants.ts b/apps/web/src/constants/font-constants.ts
new file mode 100644
index 00000000..bfddc182
--- /dev/null
+++ b/apps/web/src/constants/font-constants.ts
@@ -0,0 +1,79 @@
+export interface FontOption {
+  value: string;
+  label: string;
+  category: "system" | "google" | "custom";
+  weights?: number[];
+  hasClassName?: boolean;
+}
+
+export const FONT_OPTIONS: FontOption[] = [
+  // System fonts (always available)
+  { value: "Arial", label: "Arial", category: "system", hasClassName: false },
+  {
+    value: "Helvetica",
+    label: "Helvetica",
+    category: "system",
+    hasClassName: false,
+  },
+  {
+    value: "Times New Roman",
+    label: "Times New Roman",
+    category: "system",
+    hasClassName: false,
+  },
+  {
+    value: "Georgia",
+    label: "Georgia",
+    category: "system",
+    hasClassName: false,
+  },
+
+  // Google Fonts (loaded in layout.tsx)
+  {
+    value: "Inter",
+    label: "Inter",
+    category: "google",
+    weights: [400, 700],
+    hasClassName: true,
+  },
+  {
+    value: "Roboto",
+    label: "Roboto",
+    category: "google",
+    weights: [400, 700],
+    hasClassName: true,
+  },
+  {
+    value: "Open Sans",
+    label: "Open Sans",
+    category: "google",
+    hasClassName: true,
+  },
+  {
+    value: "Playfair Display",
+    label: "Playfair Display",
+    category: "google",
+    hasClassName: true,
+  },
+  {
+    value: "Comic Neue",
+    label: "Comic Neue",
+    category: "google",
+    hasClassName: false,
+  },
+] as const;
+
+export const DEFAULT_FONT = "Arial";
+
+// Type-safe font family union
+export type FontFamily = (typeof FONT_OPTIONS)[number]["value"];
+
+// Helper functions
+export const getFontByValue = (value: string): FontOption | undefined =>
+  FONT_OPTIONS.find((font) => font.value === value);
+
+export const getGoogleFonts = (): FontOption[] =>
+  FONT_OPTIONS.filter((font) => font.category === "google");
+
+export const getSystemFonts = (): FontOption[] =>
+  FONT_OPTIONS.filter((font) => font.category === "system");
diff --git a/apps/web/src/constants/timeline-constants.ts b/apps/web/src/constants/timeline-constants.ts
new file mode 100644
index 00000000..92045c5e
--- /dev/null
+++ b/apps/web/src/constants/timeline-constants.ts
@@ -0,0 +1,106 @@
+import type { TrackType } from "@/types/timeline";
+
+// Track color definitions
+export const TRACK_COLORS: Record<
+  TrackType,
+  { solid: string; background: string; border: string }
+> = {
+  media: {
+    solid: "bg-blue-500",
+    background: "bg-blue-500/20",
+    border: "border-white/80",
+  },
+  text: {
+    solid: "bg-[#9C4937]",
+    background: "bg-[#9C4937]",
+    border: "border-white/80",
+  },
+  audio: {
+    solid: "bg-green-500",
+    background: "bg-green-500/20",
+    border: "border-white/80",
+  },
+} as const;
+
+// Utility functions
+export function getTrackColors(type: TrackType) {
+  return TRACK_COLORS[type];
+}
+
+export function getTrackElementClasses(type: TrackType) {
+  const colors = getTrackColors(type);
+  return `${colors.background} ${colors.border}`;
+}
+
+// Track height definitions
+export const TRACK_HEIGHTS: Record<TrackType, number> = {
+  media: 65,
+  text: 25,
+  audio: 50,
+} as const;
+
+// Utility function for track heights
+export function getTrackHeight(type: TrackType): number {
+  return TRACK_HEIGHTS[type];
+}
+
+// Calculate cumulative height up to (but not including) a track index
+export function getCumulativeHeightBefore(
+  tracks: Array<{ type: TrackType }>,
+  trackIndex: number
+): number {
+  const GAP = 4; // 4px gap between tracks (equivalent to Tailwind's gap-1)
+  return tracks
+    .slice(0, trackIndex)
+    .reduce((sum, track) => sum + getTrackHeight(track.type) + GAP, 0);
+}
+
+// Calculate total height of all tracks
+export function getTotalTracksHeight(
+  tracks: Array<{ type: TrackType }>
+): number {
+  const GAP = 4; // 4px gap between tracks (equivalent to Tailwind's gap-1)
+  const tracksHeight = tracks.reduce(
+    (sum, track) => sum + getTrackHeight(track.type),
+    0
+  );
+  const gapsHeight = Math.max(0, tracks.length - 1) * GAP; // n-1 gaps for n tracks
+  return tracksHeight + gapsHeight;
+}
+
+// Other timeline constants
+export const TIMELINE_CONSTANTS = {
+  ELEMENT_MIN_WIDTH: 80,
+  PIXELS_PER_SECOND: 50,
+  TRACK_HEIGHT: 60, // Default fallback
+  DEFAULT_TEXT_DURATION: 5,
+  ZOOM_LEVELS: [0.25, 0.5, 1, 1.5, 2, 3, 4],
+} as const;
+
+// FPS presets for project settings
+export const FPS_PRESETS = [
+  { value: "24", label: "24 fps (Film)" },
+  { value: "25", label: "25 fps (PAL)" },
+  { value: "30", label: "30 fps (NTSC)" },
+  { value: "60", label: "60 fps (High)" },
+  { value: "120", label: "120 fps (Slow-mo)" },
+] as const;
+
+// Frame snapping utilities
+export function timeToFrame(time: number, fps: number): number {
+  return Math.round(time * fps);
+}
+
+export function frameToTime(frame: number, fps: number): number {
+  return frame / fps;
+}
+
+export function snapTimeToFrame(time: number, fps: number): number {
+  if (fps <= 0) return time; // Fallback for invalid FPS
+  const frame = timeToFrame(time, fps);
+  return frameToTime(frame, fps);
+}
+
+export function getFrameDuration(fps: number): number {
+  return 1 / fps;
+}