/**
 * 使用统计相关工具
 * 迁移自基线 modules/usage.js 的纯逻辑部分
 */

import type { ScriptableContext } from 'chart.js';
import { maskApiKey } from './format';

export interface KeyStatBucket {
  success: number;
  failure: number;
}

export interface KeyStats {
  bySource: Record<string, KeyStatBucket>;
  byAuthIndex: Record<string, KeyStatBucket>;
}

export interface TokenBreakdown {
  cachedTokens: number;
  reasoningTokens: number;
}

export interface RateStats {
  rpm: number;
  tpm: number;
  windowMinutes: number;
  requestCount: number;
  tokenCount: number;
}

export interface ModelPrice {
  prompt: number;
  completion: number;
  cache: number;
}

export interface UsageDetail {
  timestamp: string;
  source: string;
  auth_index: number;
  tokens: {
    input_tokens: number;
    output_tokens: number;
    reasoning_tokens: number;
    cached_tokens: number;
    cache_tokens?: number;
    total_tokens: number;
  };
  failed: boolean;
  __modelName?: string;
}

export interface ApiStats {
  endpoint: string;
  totalRequests: number;
  totalTokens: number;
  totalCost: number;
  models: Record<string, { requests: number; tokens: number }>;
}

const TOKENS_PER_PRICE_UNIT = 1_000_000;
const MODEL_PRICE_STORAGE_KEY = 'cli-proxy-model-prices-v2';

const normalizeAuthIndex = (value: any) => {
  if (typeof value === 'number' && Number.isFinite(value)) {
    return value.toString();
  }
  if (typeof value === 'string') {
    const trimmed = value.trim();
    return trimmed ? trimmed : null;
  }
  return null;
};

/**
 * 对使用数据中的敏感字段进行遮罩
 */
export function maskUsageSensitiveValue(value: unknown, masker: (val: string) => string = maskApiKey): string {
  if (value === null || value === undefined) {
    return '';
  }
  const raw = typeof value === 'string' ? value : String(value);
  if (!raw) {
    return '';
  }

  let masked = raw;

  const queryRegex = /([?&])(api[-_]?key|key|token|access_token|authorization)=([^&#\s]+)/gi;
  masked = masked.replace(queryRegex, (_full, prefix, keyName, valuePart) => `${prefix}${keyName}=${masker(valuePart)}`);

  const headerRegex = /(api[-_]?key|key|token|access[-_]?token|authorization)\s*([:=])\s*([A-Za-z0-9._-]+)/gi;
  masked = masked.replace(headerRegex, (_full, keyName, separator, valuePart) => `${keyName}${separator}${masker(valuePart)}`);

  const keyLikeRegex = /(sk-[A-Za-z0-9]{6,}|AI[a-zA-Z0-9_-]{6,}|AIza[0-9A-Za-z-_]{8,}|hf_[A-Za-z0-9]{6,}|pk_[A-Za-z0-9]{6,}|rk_[A-Za-z0-9]{6,})/g;
  masked = masked.replace(keyLikeRegex, (match) => masker(match));

  if (masked === raw) {
    const trimmed = raw.trim();
    if (trimmed && !/\s/.test(trimmed)) {
      const looksLikeKey =
        /^sk-/i.test(trimmed) ||
        /^AI/i.test(trimmed) ||
        /^AIza/i.test(trimmed) ||
        /^hf_/i.test(trimmed) ||
        /^pk_/i.test(trimmed) ||
        /^rk_/i.test(trimmed) ||
        (!/[\\/]/.test(trimmed) && (/\d/.test(trimmed) || trimmed.length >= 10)) ||
        trimmed.length >= 24;
      if (looksLikeKey) {
        return masker(trimmed);
      }
    }
  }

  return masked;
}

/**
 * 格式化 tokens 为百万单位
 */
export function formatTokensInMillions(value: number): string {
  const num = Number(value);
  if (!Number.isFinite(num)) {
    return '0.00M';
  }
  return `${(num / 1_000_000).toFixed(2)}M`;
}

/**
 * 格式化每分钟数值
 */
export function formatPerMinuteValue(value: number): string {
  const num = Number(value);
  if (!Number.isFinite(num)) {
    return '0.00';
  }
  const abs = Math.abs(num);
  if (abs >= 1000) {
    return Math.round(num).toLocaleString();
  }
  if (abs >= 100) {
    return num.toFixed(0);
  }
  if (abs >= 10) {
    return num.toFixed(1);
  }
  return num.toFixed(2);
}

/**
 * 格式化紧凑数字
 */
export function formatCompactNumber(value: number): string {
  const num = Number(value);
  if (!Number.isFinite(num)) {
    return '0';
  }
  const abs = Math.abs(num);
  if (abs >= 1_000_000) {
    return `${(num / 1_000_000).toFixed(1)}M`;
  }
  if (abs >= 1_000) {
    return `${(num / 1_000).toFixed(1)}K`;
  }
  return abs >= 1 ? num.toFixed(0) : num.toFixed(2);
}

/**
 * 格式化美元
 */
export function formatUsd(value: number): string {
  const num = Number(value);
  if (!Number.isFinite(num)) {
    return '$0.00';
  }
  const fixed = num.toFixed(2);
  const parts = Number(fixed).toLocaleString(undefined, {
    minimumFractionDigits: 2,
    maximumFractionDigits: 2
  });
  return `$${parts}`;
}

/**
 * 从使用数据中收集所有请求明细
 */
export function collectUsageDetails(usageData: any): UsageDetail[] {
  if (!usageData) {
    return [];
  }
  const apis = usageData.apis || {};
  const details: UsageDetail[] = [];
  Object.values(apis as Record<string, any>).forEach((apiEntry) => {
    const models = apiEntry?.models || {};
    Object.entries(models as Record<string, any>).forEach(([modelName, modelEntry]) => {
      const modelDetails = Array.isArray(modelEntry.details) ? modelEntry.details : [];
      modelDetails.forEach((detail: any) => {
        if (detail && detail.timestamp) {
          details.push({
            ...detail,
            __modelName: modelName
          });
        }
      });
    });
  });
  return details;
}

/**
 * 从单条明细提取总 tokens
 */
export function extractTotalTokens(detail: any): number {
  const tokens = detail?.tokens || {};
  if (typeof tokens.total_tokens === 'number') {
    return tokens.total_tokens;
  }
  const inputTokens = typeof tokens.input_tokens === 'number' ? tokens.input_tokens : 0;
  const outputTokens = typeof tokens.output_tokens === 'number' ? tokens.output_tokens : 0;
  const reasoningTokens = typeof tokens.reasoning_tokens === 'number' ? tokens.reasoning_tokens : 0;
  const cachedTokens = Math.max(
    typeof tokens.cached_tokens === 'number' ? Math.max(tokens.cached_tokens, 0) : 0,
    typeof tokens.cache_tokens === 'number' ? Math.max(tokens.cache_tokens, 0) : 0
  );

  return inputTokens + outputTokens + reasoningTokens + cachedTokens;
}

/**
 * 计算 token 分类统计
 */
export function calculateTokenBreakdown(usageData: any): TokenBreakdown {
  const details = collectUsageDetails(usageData);
  if (!details.length) {
    return { cachedTokens: 0, reasoningTokens: 0 };
  }

  let cachedTokens = 0;
  let reasoningTokens = 0;

  details.forEach(detail => {
    const tokens = detail?.tokens || {};
    cachedTokens += Math.max(
      typeof tokens.cached_tokens === 'number' ? Math.max(tokens.cached_tokens, 0) : 0,
      typeof tokens.cache_tokens === 'number' ? Math.max(tokens.cache_tokens, 0) : 0
    );
    if (typeof tokens.reasoning_tokens === 'number') {
      reasoningTokens += tokens.reasoning_tokens;
    }
  });

  return { cachedTokens, reasoningTokens };
}

/**
 * 计算最近 N 分钟的 RPM/TPM
 */
export function calculateRecentPerMinuteRates(windowMinutes: number = 30, usageData: any): RateStats {
  const details = collectUsageDetails(usageData);
  const effectiveWindow = Number.isFinite(windowMinutes) && windowMinutes > 0 ? windowMinutes : 30;

  if (!details.length) {
    return { rpm: 0, tpm: 0, windowMinutes: effectiveWindow, requestCount: 0, tokenCount: 0 };
  }

  const now = Date.now();
  const windowStart = now - effectiveWindow * 60 * 1000;
  let requestCount = 0;
  let tokenCount = 0;

  details.forEach(detail => {
    const timestamp = Date.parse(detail.timestamp);
    if (Number.isNaN(timestamp) || timestamp < windowStart) {
      return;
    }
    requestCount += 1;
    tokenCount += extractTotalTokens(detail);
  });

  const denominator = effectiveWindow > 0 ? effectiveWindow : 1;
  return {
    rpm: requestCount / denominator,
    tpm: tokenCount / denominator,
    windowMinutes: effectiveWindow,
    requestCount,
    tokenCount
  };
}

/**
 * 从使用数据获取模型名称列表
 */
export function getModelNamesFromUsage(usageData: any): string[] {
  if (!usageData) {
    return [];
  }
  const apis = usageData.apis || {};
  const names = new Set<string>();
  Object.values(apis as Record<string, any>).forEach(apiEntry => {
    const models = apiEntry?.models || {};
    Object.keys(models).forEach(modelName => {
      if (modelName) {
        names.add(modelName);
      }
    });
  });
  return Array.from(names).sort((a, b) => a.localeCompare(b));
}

/**
 * 计算成本数据
 */
export function calculateCost(detail: any, modelPrices: Record<string, ModelPrice>): number {
  const modelName = detail.__modelName || '';
  const price = modelPrices[modelName];
  if (!price) {
    return 0;
  }
  const tokens = detail?.tokens || {};
  const rawInputTokens = Number(tokens.input_tokens);
  const rawCompletionTokens = Number(tokens.output_tokens);
  const rawCachedTokensPrimary = Number(tokens.cached_tokens);
  const rawCachedTokensAlternate = Number(tokens.cache_tokens);

  const inputTokens = Number.isFinite(rawInputTokens) ? Math.max(rawInputTokens, 0) : 0;
  const completionTokens = Number.isFinite(rawCompletionTokens) ? Math.max(rawCompletionTokens, 0) : 0;
  const cachedTokens = Math.max(
    Number.isFinite(rawCachedTokensPrimary) ? Math.max(rawCachedTokensPrimary, 0) : 0,
    Number.isFinite(rawCachedTokensAlternate) ? Math.max(rawCachedTokensAlternate, 0) : 0
  );
  const promptTokens = Math.max(inputTokens - cachedTokens, 0);

  const promptCost = (promptTokens / TOKENS_PER_PRICE_UNIT) * (Number(price.prompt) || 0);
  const cachedCost = (cachedTokens / TOKENS_PER_PRICE_UNIT) * (Number(price.cache) || 0);
  const completionCost = (completionTokens / TOKENS_PER_PRICE_UNIT) * (Number(price.completion) || 0);
  const total = promptCost + cachedCost + completionCost;
  return Number.isFinite(total) && total > 0 ? total : 0;
}

/**
 * 计算总成本
 */
export function calculateTotalCost(usageData: any, modelPrices: Record<string, ModelPrice>): number {
  const details = collectUsageDetails(usageData);
  if (!details.length || !Object.keys(modelPrices).length) {
    return 0;
  }
  return details.reduce((sum, detail) => sum + calculateCost(detail, modelPrices), 0);
}

/**
 * 从 localStorage 加载模型价格
 */
export function loadModelPrices(): Record<string, ModelPrice> {
  try {
    if (typeof localStorage === 'undefined') {
      return {};
    }
    const raw = localStorage.getItem(MODEL_PRICE_STORAGE_KEY);
    if (!raw) {
      return {};
    }
    const parsed = JSON.parse(raw);
    if (!parsed || typeof parsed !== 'object') {
      return {};
    }
    const normalized: Record<string, ModelPrice> = {};
    Object.entries(parsed).forEach(([model, price]: [string, any]) => {
      if (!model) return;
      const promptRaw = Number(price?.prompt);
      const completionRaw = Number(price?.completion);
      const cacheRaw = Number(price?.cache);

      if (!Number.isFinite(promptRaw) && !Number.isFinite(completionRaw) && !Number.isFinite(cacheRaw)) {
        return;
      }

      const prompt = Number.isFinite(promptRaw) && promptRaw >= 0 ? promptRaw : 0;
      const completion = Number.isFinite(completionRaw) && completionRaw >= 0 ? completionRaw : 0;
      const cache =
        Number.isFinite(cacheRaw) && cacheRaw >= 0
          ? cacheRaw
          : Number.isFinite(promptRaw) && promptRaw >= 0
            ? promptRaw
            : prompt;

      normalized[model] = {
        prompt,
        completion,
        cache
      };
    });
    return normalized;
  } catch {
    return {};
  }
}

/**
 * 保存模型价格到 localStorage
 */
export function saveModelPrices(prices: Record<string, ModelPrice>): void {
  try {
    if (typeof localStorage === 'undefined') {
      return;
    }
    localStorage.setItem(MODEL_PRICE_STORAGE_KEY, JSON.stringify(prices));
  } catch {
    console.warn('保存模型价格失败');
  }
}

/**
 * 获取 API 统计数据
 */
export function getApiStats(usageData: any, modelPrices: Record<string, ModelPrice>): ApiStats[] {
  if (!usageData?.apis) {
    return [];
  }
  const apis = usageData.apis;
  const result: ApiStats[] = [];

  Object.entries(apis as Record<string, any>).forEach(([endpoint, apiData]) => {
    const models: Record<string, { requests: number; tokens: number }> = {};
    let totalCost = 0;

    const modelsData = apiData?.models || {};
    Object.entries(modelsData as Record<string, any>).forEach(([modelName, modelData]) => {
      models[modelName] = {
        requests: modelData.total_requests || 0,
        tokens: modelData.total_tokens || 0
      };

      const price = modelPrices[modelName];
      if (price) {
        const details = Array.isArray(modelData.details) ? modelData.details : [];
        details.forEach((detail: any) => {
          totalCost += calculateCost({ ...detail, __modelName: modelName }, modelPrices);
        });
      }
    });

    result.push({
      endpoint: maskUsageSensitiveValue(endpoint) || endpoint,
      totalRequests: apiData.total_requests || 0,
      totalTokens: apiData.total_tokens || 0,
      totalCost,
      models
    });
  });

  return result;
}

/**
 * 获取模型统计数据
 */
export function getModelStats(usageData: any, modelPrices: Record<string, ModelPrice>): Array<{
  model: string;
  requests: number;
  tokens: number;
  cost: number;
}> {
  if (!usageData?.apis) {
    return [];
  }

  const modelMap = new Map<string, { requests: number; tokens: number; cost: number }>();

  Object.values(usageData.apis as Record<string, any>).forEach(apiData => {
    const models = apiData?.models || {};
    Object.entries(models as Record<string, any>).forEach(([modelName, modelData]) => {
      const existing = modelMap.get(modelName) || { requests: 0, tokens: 0, cost: 0 };
      existing.requests += modelData.total_requests || 0;
      existing.tokens += modelData.total_tokens || 0;

      const price = modelPrices[modelName];
      if (price) {
        const details = Array.isArray(modelData.details) ? modelData.details : [];
        details.forEach((detail: any) => {
          existing.cost += calculateCost({ ...detail, __modelName: modelName }, modelPrices);
        });
      }
      modelMap.set(modelName, existing);
    });
  });

  return Array.from(modelMap.entries())
    .map(([model, stats]) => ({ model, ...stats }))
    .sort((a, b) => b.requests - a.requests);
}

/**
 * 格式化小时标签
 */
export function formatHourLabel(date: Date): string {
  if (!(date instanceof Date)) {
    return '';
  }
  const month = (date.getMonth() + 1).toString().padStart(2, '0');
  const day = date.getDate().toString().padStart(2, '0');
  const hour = date.getHours().toString().padStart(2, '0');
  return `${month}-${day} ${hour}:00`;
}

/**
 * 格式化日期标签
 */
export function formatDayLabel(date: Date): string {
  if (!(date instanceof Date)) {
    return '';
  }
  const year = date.getFullYear();
  const month = (date.getMonth() + 1).toString().padStart(2, '0');
  const day = date.getDate().toString().padStart(2, '0');
  return `${year}-${month}-${day}`;
}

/**
 * 构建小时级别的数据序列
 */
export function buildHourlySeriesByModel(usageData: any, metric: 'requests' | 'tokens' = 'requests'): {
  labels: string[];
  dataByModel: Map<string, number[]>;
  hasData: boolean;
} {
  const hourMs = 60 * 60 * 1000;
  const now = new Date();
  const currentHour = new Date(now);
  currentHour.setMinutes(0, 0, 0);

  const earliestBucket = new Date(currentHour);
  earliestBucket.setHours(earliestBucket.getHours() - 23);
  const earliestTime = earliestBucket.getTime();

  const labels: string[] = [];
  for (let i = 0; i < 24; i++) {
    const bucketStart = earliestTime + i * hourMs;
    labels.push(formatHourLabel(new Date(bucketStart)));
  }

  const details = collectUsageDetails(usageData);
  const dataByModel = new Map<string, number[]>();
  let hasData = false;

  if (!details.length) {
    return { labels, dataByModel, hasData };
  }

  details.forEach(detail => {
    const timestamp = Date.parse(detail.timestamp);
    if (Number.isNaN(timestamp)) {
      return;
    }

    const normalized = new Date(timestamp);
    normalized.setMinutes(0, 0, 0);
    const bucketStart = normalized.getTime();
    const lastBucketTime = earliestTime + (labels.length - 1) * hourMs;
    if (bucketStart < earliestTime || bucketStart > lastBucketTime) {
      return;
    }

    const bucketIndex = Math.floor((bucketStart - earliestTime) / hourMs);
    if (bucketIndex < 0 || bucketIndex >= labels.length) {
      return;
    }

    const modelName = detail.__modelName || 'Unknown';
    if (!dataByModel.has(modelName)) {
      dataByModel.set(modelName, new Array(labels.length).fill(0));
    }

    const bucketValues = dataByModel.get(modelName)!;
    if (metric === 'tokens') {
      bucketValues[bucketIndex] += extractTotalTokens(detail);
    } else {
      bucketValues[bucketIndex] += 1;
    }
    hasData = true;
  });

  return { labels, dataByModel, hasData };
}

/**
 * 构建日级别的数据序列
 */
export function buildDailySeriesByModel(usageData: any, metric: 'requests' | 'tokens' = 'requests'): {
  labels: string[];
  dataByModel: Map<string, number[]>;
  hasData: boolean;
} {
  const details = collectUsageDetails(usageData);
  const valuesByModel = new Map<string, Map<string, number>>();
  const labelsSet = new Set<string>();
  let hasData = false;

  if (!details.length) {
    return { labels: [], dataByModel: new Map(), hasData };
  }

  details.forEach(detail => {
    const timestamp = Date.parse(detail.timestamp);
    if (Number.isNaN(timestamp)) {
      return;
    }
    const dayLabel = formatDayLabel(new Date(timestamp));
    if (!dayLabel) {
      return;
    }

    const modelName = detail.__modelName || 'Unknown';
    if (!valuesByModel.has(modelName)) {
      valuesByModel.set(modelName, new Map());
    }
    const modelDayMap = valuesByModel.get(modelName)!;
    const increment = metric === 'tokens' ? extractTotalTokens(detail) : 1;
    modelDayMap.set(dayLabel, (modelDayMap.get(dayLabel) || 0) + increment);
    labelsSet.add(dayLabel);
    hasData = true;
  });

  const labels = Array.from(labelsSet).sort();
  const dataByModel = new Map<string, number[]>();
  valuesByModel.forEach((dayMap, modelName) => {
    const series = labels.map(label => dayMap.get(label) || 0);
    dataByModel.set(modelName, series);
  });

  return { labels, dataByModel, hasData };
}

export interface ChartDataset {
  label: string;
  data: number[];
  borderColor: string;
  backgroundColor: string | CanvasGradient | ((context: ScriptableContext<'line'>) => string | CanvasGradient);
  fill: boolean;
  tension: number;
}

export interface ChartData {
  labels: string[];
  datasets: ChartDataset[];
}

const CHART_COLORS = [
  { borderColor: '#3b82f6', backgroundColor: 'rgba(59, 130, 246, 0.15)' },
  { borderColor: '#22c55e', backgroundColor: 'rgba(34, 197, 94, 0.15)' },
  { borderColor: '#f59e0b', backgroundColor: 'rgba(245, 158, 11, 0.15)' },
  { borderColor: '#ef4444', backgroundColor: 'rgba(239, 68, 68, 0.15)' },
  { borderColor: '#8b5cf6', backgroundColor: 'rgba(139, 92, 246, 0.15)' },
  { borderColor: '#06b6d4', backgroundColor: 'rgba(6, 182, 212, 0.15)' },
  { borderColor: '#ec4899', backgroundColor: 'rgba(236, 72, 153, 0.15)' },
  { borderColor: '#84cc16', backgroundColor: 'rgba(132, 204, 22, 0.15)' },
  { borderColor: '#f97316', backgroundColor: 'rgba(249, 115, 22, 0.15)' },
];

const clamp = (value: number, min: number, max: number) => Math.min(Math.max(value, min), max);

const hexToRgb = (hex: string): { r: number; g: number; b: number } | null => {
  const normalized = hex.trim().replace('#', '');
  if (normalized.length !== 6) {
    return null;
  }
  const r = Number.parseInt(normalized.slice(0, 2), 16);
  const g = Number.parseInt(normalized.slice(2, 4), 16);
  const b = Number.parseInt(normalized.slice(4, 6), 16);
  if (![r, g, b].every((channel) => Number.isFinite(channel))) {
    return null;
  }
  return { r, g, b };
};

const withAlpha = (hex: string, alpha: number) => {
  const rgb = hexToRgb(hex);
  if (!rgb) {
    return hex;
  }
  const clamped = clamp(alpha, 0, 1);
  return `rgba(${rgb.r}, ${rgb.g}, ${rgb.b}, ${clamped})`;
};

const buildAreaGradient = (context: ScriptableContext<'line'>, baseHex: string, fallback: string) => {
  const chart = context.chart;
  const ctx = chart.ctx;
  const area = chart.chartArea;

  if (!area) {
    return fallback;
  }

  const gradient = ctx.createLinearGradient(0, area.top, 0, area.bottom);
  gradient.addColorStop(0, withAlpha(baseHex, 0.28));
  gradient.addColorStop(0.6, withAlpha(baseHex, 0.12));
  gradient.addColorStop(1, withAlpha(baseHex, 0.02));
  return gradient;
};

/**
 * 构建图表数据
 */
export function buildChartData(
  usageData: any,
  period: 'hour' | 'day' = 'day',
  metric: 'requests' | 'tokens' = 'requests',
  selectedModels: string[] = []
): ChartData {
  const baseSeries = period === 'hour'
    ? buildHourlySeriesByModel(usageData, metric)
    : buildDailySeriesByModel(usageData, metric);

  const { labels, dataByModel } = baseSeries;

  // Build "All" series as sum of all models
  const getAllSeries = (): number[] => {
    const summed = new Array(labels.length).fill(0);
    dataByModel.forEach(values => {
      values.forEach((value, idx) => {
        summed[idx] = (summed[idx] || 0) + value;
      });
    });
    return summed;
  };

  // Determine which models to show
  const modelsToShow = selectedModels.length > 0 ? selectedModels : ['all'];

  const datasets: ChartDataset[] = modelsToShow.map((model, index) => {
    const isAll = model === 'all';
    const data = isAll ? getAllSeries() : (dataByModel.get(model) || new Array(labels.length).fill(0));
    const colorIndex = index % CHART_COLORS.length;
    const style = CHART_COLORS[colorIndex];
    const shouldFill = modelsToShow.length === 1 || (isAll && modelsToShow.length > 1);

    return {
      label: isAll ? 'All Models' : model,
      data,
      borderColor: style.borderColor,
      backgroundColor: shouldFill
        ? (ctx) => buildAreaGradient(ctx, style.borderColor, style.backgroundColor)
        : style.backgroundColor,
      fill: shouldFill,
      tension: 0.35
    };
  });

  return { labels, datasets };
}

/**
 * 依据 usage 数据计算密钥使用统计
 */
/**
 * 状态栏单个格子的状态
 */
export type StatusBlockState = 'success' | 'failure' | 'mixed' | 'idle';

/**
 * 状态栏数据
 */
export interface StatusBarData {
  blocks: StatusBlockState[];
  successRate: number;
  totalSuccess: number;
  totalFailure: number;
}

/**
 * 计算状态栏数据（最近1小时，分为20个5分钟的时间块）
 * 注意：20个块 × 5分钟 = 100分钟，但我们只使用最近60分钟的数据
 * 所以实际只有最后12个块可能有数据，前8个块将始终为 idle
 */
export function calculateStatusBarData(
  usageDetails: UsageDetail[],
  sourceFilter?: string,
  authIndexFilter?: number
): StatusBarData {
  const BLOCK_COUNT = 20;
  const BLOCK_DURATION_MS = 5 * 60 * 1000; // 5 minutes
  const HOUR_MS = 60 * 60 * 1000;

  const now = Date.now();
  const hourAgo = now - HOUR_MS;

  // Initialize blocks
  const blockStats: Array<{ success: number; failure: number }> = Array.from(
    { length: BLOCK_COUNT },
    () => ({ success: 0, failure: 0 })
  );

  let totalSuccess = 0;
  let totalFailure = 0;

  // Filter and bucket the usage details
  usageDetails.forEach((detail) => {
    const timestamp = Date.parse(detail.timestamp);
    if (Number.isNaN(timestamp) || timestamp < hourAgo || timestamp > now) {
      return;
    }

    // Apply filters if provided
    if (sourceFilter !== undefined && detail.source !== sourceFilter) {
      return;
    }
    if (authIndexFilter !== undefined && detail.auth_index !== authIndexFilter) {
      return;
    }

    // Calculate which block this falls into (0 = oldest, 19 = newest)
    const ageMs = now - timestamp;
    const blockIndex = BLOCK_COUNT - 1 - Math.floor(ageMs / BLOCK_DURATION_MS);

    if (blockIndex >= 0 && blockIndex < BLOCK_COUNT) {
      if (detail.failed) {
        blockStats[blockIndex].failure += 1;
        totalFailure += 1;
      } else {
        blockStats[blockIndex].success += 1;
        totalSuccess += 1;
      }
    }
  });

  // Convert stats to block states
  const blocks: StatusBlockState[] = blockStats.map((stat) => {
    if (stat.success === 0 && stat.failure === 0) {
      return 'idle';
    }
    if (stat.failure === 0) {
      return 'success';
    }
    if (stat.success === 0) {
      return 'failure';
    }
    return 'mixed';
  });

  // Calculate success rate
  const total = totalSuccess + totalFailure;
  const successRate = total > 0 ? (totalSuccess / total) * 100 : 100;

  return {
    blocks,
    successRate,
    totalSuccess,
    totalFailure
  };
}

export function computeKeyStats(usageData: any, masker: (val: string) => string = maskApiKey): KeyStats {
  if (!usageData) {
    return { bySource: {}, byAuthIndex: {} };
  }

  const sourceStats: Record<string, KeyStatBucket> = {};
  const authIndexStats: Record<string, KeyStatBucket> = {};

  const ensureBucket = (bucket: Record<string, KeyStatBucket>, key: string) => {
    if (!bucket[key]) {
      bucket[key] = { success: 0, failure: 0 };
    }
    return bucket[key];
  };

  const apis = usageData.apis || {};
  Object.values(apis as any).forEach((apiEntry: any) => {
    const models = apiEntry?.models || {};

    Object.values(models as any).forEach((modelEntry: any) => {
      const details = modelEntry?.details || [];

      details.forEach((detail: any) => {
        const source = maskUsageSensitiveValue(detail?.source, masker);
        const authIndexKey = normalizeAuthIndex(detail?.auth_index);
        const isFailed = detail?.failed === true;

        if (source) {
          const bucket = ensureBucket(sourceStats, source);
          if (isFailed) {
            bucket.failure += 1;
          } else {
            bucket.success += 1;
          }
        }

        if (authIndexKey) {
          const bucket = ensureBucket(authIndexStats, authIndexKey);
          if (isFailed) {
            bucket.failure += 1;
          } else {
            bucket.success += 1;
          }
        }
      });
    });
  });

  return {
    bySource: sourceStats,
    byAuthIndex: authIndexStats
  };
}