Stop_smoking_website_ver2/src/lib/storage.ts

// Client-side storage utilities for tracking data
// All data is stored per-user using their unique ID as a prefix

export interface UsageEntry {
  date: string; // ISO date string YYYY-MM-DD
  count: number;
  substance: 'nicotine' | 'weed';
}

export interface UserPreferences {
  substance: 'nicotine' | 'weed';
  trackingStartDate: string | null;
  hasCompletedSetup: boolean;
  dailyGoal: number | null;
  quitPlan: QuitPlan | null;
  userName: string | null;
  userAge: number | null;
}

export interface QuitPlan {
  startDate: string;
  endDate: string;
  weeklyTargets: number[];
  baselineAverage: number;
}

const CURRENT_USER_KEY = 'quit_smoking_current_user';

function getStorageKey(baseKey: string, userId?: string): string {
  const uid = userId || getCurrentUserId();
  if (!uid) return baseKey;
  return `${baseKey}_${uid}`;
}

export function setCurrentUserId(userId: string): void {
  if (typeof window === 'undefined') return;
  localStorage.setItem(CURRENT_USER_KEY, userId);
}

export function getCurrentUserId(): string | null {
  if (typeof window === 'undefined') return null;
  return localStorage.getItem(CURRENT_USER_KEY);
}

export function getUsageData(userId?: string): UsageEntry[] {
  if (typeof window === 'undefined') return [];
  const key = getStorageKey('quit_smoking_usage', userId);
  const data = localStorage.getItem(key);
  return data ? JSON.parse(data) : [];
}

export function saveUsageEntry(entry: UsageEntry, userId?: string): void {
  if (typeof window === 'undefined') return;
  const key = getStorageKey('quit_smoking_usage', userId);
  const data = getUsageData(userId);
  const existingIndex = data.findIndex(
    (e) => e.date === entry.date && e.substance === entry.substance
  );

  if (existingIndex >= 0) {
    data[existingIndex].count += entry.count;
  } else {
    data.push(entry);
  }

  localStorage.setItem(key, JSON.stringify(data));
}

export function setUsageForDate(date: string, count: number, substance: 'nicotine' | 'weed', userId?: string): void {
  if (typeof window === 'undefined') return;
  const key = getStorageKey('quit_smoking_usage', userId);
  const data = getUsageData(userId);
  const existingIndex = data.findIndex(
    (e) => e.date === date && e.substance === substance
  );

  if (existingIndex >= 0) {
    data[existingIndex].count = count;
  } else {
    data.push({ date, count, substance });
  }

  localStorage.setItem(key, JSON.stringify(data));
}

export function getUsageForDate(date: string, substance: 'nicotine' | 'weed', userId?: string): number {
  const data = getUsageData(userId);
  const entry = data.find((e) => e.date === date && e.substance === substance);
  return entry?.count ?? 0;
}

export function getPreferences(userId?: string): UserPreferences {
  const defaultPrefs: UserPreferences = {
    substance: 'nicotine',
    trackingStartDate: null,
    hasCompletedSetup: false,
    dailyGoal: null,
    quitPlan: null,
    userName: null,
    userAge: null,
  };

  if (typeof window === 'undefined') {
    return defaultPrefs;
  }

  const key = getStorageKey('quit_smoking_preferences', userId);
  const data = localStorage.getItem(key);
  if (!data) {
    return defaultPrefs;
  }

  return { ...defaultPrefs, ...JSON.parse(data) };
}

export function savePreferences(preferences: UserPreferences, userId?: string): void {
  if (typeof window === 'undefined') return;
  const key = getStorageKey('quit_smoking_preferences', userId);
  localStorage.setItem(key, JSON.stringify(preferences));
}

export function getLastPromptDate(userId?: string): string | null {
  if (typeof window === 'undefined') return null;
  const key = getStorageKey('quit_smoking_last_prompt', userId);
  return localStorage.getItem(key);
}

export function setLastPromptDate(date: string, userId?: string): void {
  if (typeof window === 'undefined') return;
  const key = getStorageKey('quit_smoking_last_prompt', userId);
  localStorage.setItem(key, date);
}

export function shouldShowUsagePrompt(): boolean {
  // Always show the prompt - users can log multiple times throughout the day
  return true;
}

export function getWeeklyData(substance: 'nicotine' | 'weed', userId?: string): UsageEntry[] {
  const data = getUsageData(userId);
  const today = new Date();
  const weekAgo = new Date(today);
  weekAgo.setDate(weekAgo.getDate() - 7);

  return data.filter((entry) => {
    const entryDate = new Date(entry.date);
    return entry.substance === substance && entryDate >= weekAgo && entryDate <= today;
  });
}

export function calculateWeeklyAverage(substance: 'nicotine' | 'weed', userId?: string): number {
  const weeklyData = getWeeklyData(substance, userId);
  if (weeklyData.length === 0) return 0;

  const total = weeklyData.reduce((sum, entry) => sum + entry.count, 0);
  return Math.round(total / weeklyData.length);
}

export function hasOneWeekOfData(substance: 'nicotine' | 'weed', userId?: string): boolean {
  const prefs = getPreferences(userId);
  if (!prefs.trackingStartDate) return false;

  const startDate = new Date(prefs.trackingStartDate);
  const today = new Date();
  const daysDiff = Math.floor((today.getTime() - startDate.getTime()) / (1000 * 60 * 60 * 24));

  return daysDiff >= 7;
}

export function generateQuitPlan(substance: 'nicotine' | 'weed', userId?: string): QuitPlan {
  const baseline = calculateWeeklyAverage(substance, userId);
  const today = new Date();
  const startDate = today.toISOString().split('T')[0];

  // 6-week reduction plan
  const endDate = new Date(today);
  endDate.setDate(endDate.getDate() + 42);

  // Gradual reduction: each week reduce by ~15-20%
  const weeklyTargets: number[] = [];
  let current = baseline;
  for (let i = 0; i < 6; i++) {
    current = Math.max(0, Math.round(current * 0.8));
    weeklyTargets.push(current);
  }

  return {
    startDate,
    endDate: endDate.toISOString().split('T')[0],
    weeklyTargets,
    baselineAverage: baseline,
  };
}

export function getCurrentWeekTarget(userId?: string): number | null {
  const prefs = getPreferences(userId);
  if (!prefs.quitPlan) return null;

  const startDate = new Date(prefs.quitPlan.startDate);
  const today = new Date();
  const weekNumber = Math.floor((today.getTime() - startDate.getTime()) / (1000 * 60 * 60 * 24 * 7));

  if (weekNumber >= prefs.quitPlan.weeklyTargets.length) {
    return 0; // Goal achieved
  }

  return prefs.quitPlan.weeklyTargets[weekNumber];
}

export function clearDayData(date: string, substance: 'nicotine' | 'weed', userId?: string): void {
  if (typeof window === 'undefined') return;
  const key = getStorageKey('quit_smoking_usage', userId);
  const data = getUsageData(userId);
  const filtered = data.filter((e) => !(e.date === date && e.substance === substance));
  localStorage.setItem(key, JSON.stringify(filtered));
}

export function clearAllData(userId?: string): void {
  if (typeof window === 'undefined') return;
  const usageKey = getStorageKey('quit_smoking_usage', userId);
  const prefsKey = getStorageKey('quit_smoking_preferences', userId);
  const promptKey = getStorageKey('quit_smoking_last_prompt', userId);
  localStorage.removeItem(usageKey);
  localStorage.removeItem(prefsKey);
  localStorage.removeItem(promptKey);
}