import { createHash } from 'node:crypto';
import type {
  CompanyAiReport,
  CompanyAnalysis,
  Filing,
  Holding,
  ResearchJournalEntry,
  ResearchMemo,
  WatchlistItem
} from '@/lib/types';
import { synthesizeCompanyOverview } from '@/lib/server/company-overview-synthesis';
import { getPriceHistory, getQuote } from '@/lib/server/prices';
import { getRecentDevelopments } from '@/lib/server/recent-developments';
import { deriveValuationSnapshot, getSecCompanyProfile, toCompanyProfile } from '@/lib/server/sec-company-profile';
import { getCompanyDescription } from '@/lib/server/sec-description';
import { getYahooCompanyDescription } from '@/lib/server/yahoo-company-profile';
import { redactInternalFilingAnalysisFields } from '@/lib/server/api/filing-redaction';
import { listFilingsRecords } from '@/lib/server/repos/filings';
import { getHoldingByTicker } from '@/lib/server/repos/holdings';
import { getResearchMemoByTicker } from '@/lib/server/repos/research-library';
import { listResearchJournalEntries } from '@/lib/server/repos/research-journal';
import { getWatchlistItemByTicker } from '@/lib/server/repos/watchlist';
import {
  CURRENT_COMPANY_OVERVIEW_CACHE_VERSION,
  getCompanyOverviewCache,
  upsertCompanyOverviewCache
} from '@/lib/server/repos/company-overview-cache';

const FINANCIAL_FORMS = new Set<Filing['filing_type']>(['10-K', '10-Q']);
const COMPANY_OVERVIEW_CACHE_TTL_MS = 1000 * 60 * 15;

export type CompanyAnalysisLocalInputs = {
  filings: Filing[];
  holding: Holding | null;
  watchlistItem: WatchlistItem | null;
  journalPreview: ResearchJournalEntry[];
  memo: ResearchMemo | null;
};

function withFinancialMetricsPolicy(filing: Filing): Filing {
  if (FINANCIAL_FORMS.has(filing.filing_type)) {
    return filing;
  }

  return {
    ...filing,
    metrics: null
  };
}

export function buildCompanyAnalysisSourceSignature(input: {
  ticker: string;
  localInputs: CompanyAnalysisLocalInputs;
  cacheVersion?: number;
}) {
  const payload = {
    ticker: input.ticker.trim().toUpperCase(),
    cacheVersion: input.cacheVersion ?? CURRENT_COMPANY_OVERVIEW_CACHE_VERSION,
    filings: input.localInputs.filings.map((filing) => ({
      accessionNumber: filing.accession_number,
      updatedAt: filing.updated_at
    })),
    memoUpdatedAt: input.localInputs.memo?.updated_at ?? null,
    watchlistUpdatedAt: input.localInputs.watchlistItem?.updated_at ?? null,
    holdingUpdatedAt: input.localInputs.holding?.updated_at ?? null,
    journalPreview: input.localInputs.journalPreview.map((entry) => ({
      id: entry.id,
      updatedAt: entry.updated_at
    }))
  };

  return createHash('sha256').update(JSON.stringify(payload)).digest('hex');
}

export function isCompanyOverviewCacheFresh(input: {
  updatedAt: string;
  sourceSignature: string;
  expectedSourceSignature: string;
  cacheVersion: number;
  refresh?: boolean;
  ttlMs?: number;
  now?: Date;
}) {
  if (input.refresh) {
    return false;
  }

  if (input.cacheVersion !== CURRENT_COMPANY_OVERVIEW_CACHE_VERSION) {
    return false;
  }

  if (input.sourceSignature !== input.expectedSourceSignature) {
    return false;
  }

  const now = input.now ?? new Date();
  const updatedAt = Date.parse(input.updatedAt);
  if (!Number.isFinite(updatedAt)) {
    return false;
  }

  return now.getTime() - updatedAt <= (input.ttlMs ?? COMPANY_OVERVIEW_CACHE_TTL_MS);
}

async function getCompanyAnalysisLocalInputs(input: { userId: string; ticker: string }): Promise<CompanyAnalysisLocalInputs> {
  const ticker = input.ticker.trim().toUpperCase();

  const [filings, holding, watchlistItem, journalPreview, memo] = await Promise.all([
    listFilingsRecords({ ticker, limit: 40 }),
    getHoldingByTicker(input.userId, ticker),
    getWatchlistItemByTicker(input.userId, ticker),
    listResearchJournalEntries(input.userId, ticker, 6),
    getResearchMemoByTicker(input.userId, ticker)
  ]);

  return {
    filings,
    holding,
    watchlistItem,
    journalPreview,
    memo
  };
}

async function buildCompanyAnalysisPayload(input: {
  userId: string;
  ticker: string;
  localInputs: CompanyAnalysisLocalInputs;
}): Promise<CompanyAnalysis> {
  const ticker = input.ticker.trim().toUpperCase();
  const redactedFilings = input.localInputs.filings
    .map(redactInternalFilingAnalysisFields)
    .map(withFinancialMetricsPolicy);

  const [liveQuote, priceHistory, benchmarkHistory, secProfile] = await Promise.all([
    getQuote(ticker),
    getPriceHistory(ticker),
    getPriceHistory('^GSPC'),
    getSecCompanyProfile(ticker)
  ]);

  const latestFiling = redactedFilings[0] ?? null;
  const companyName = latestFiling?.company_name
    ?? secProfile?.companyName
    ?? input.localInputs.holding?.company_name
    ?? input.localInputs.watchlistItem?.company_name
    ?? ticker;

  const financials = redactedFilings
    .filter((entry) => entry.metrics && FINANCIAL_FORMS.has(entry.filing_type))
    .map((entry) => ({
      filingDate: entry.filing_date,
      filingType: entry.filing_type,
      revenue: entry.metrics?.revenue ?? null,
      netIncome: entry.metrics?.netIncome ?? null,
      totalAssets: entry.metrics?.totalAssets ?? null,
      cash: entry.metrics?.cash ?? null,
      debt: entry.metrics?.debt ?? null
    }));

  const aiReports: CompanyAiReport[] = redactedFilings
    .filter((entry) => entry.analysis?.text || entry.analysis?.legacyInsights)
    .slice(0, 8)
    .map((entry) => ({
      accessionNumber: entry.accession_number,
      filingDate: entry.filing_date,
      filingType: entry.filing_type,
      provider: entry.analysis?.provider ?? 'unknown',
      model: entry.analysis?.model ?? 'unknown',
      summary: entry.analysis?.text ?? entry.analysis?.legacyInsights ?? ''
    }));

  const latestMetricsFiling = redactedFilings.find((entry) => entry.metrics) ?? null;
  const referenceMetrics = latestMetricsFiling?.metrics ?? null;
  const keyMetrics = {
    referenceDate: latestMetricsFiling?.filing_date ?? latestFiling?.filing_date ?? null,
    revenue: referenceMetrics?.revenue ?? null,
    netIncome: referenceMetrics?.netIncome ?? null,
    totalAssets: referenceMetrics?.totalAssets ?? null,
    cash: referenceMetrics?.cash ?? null,
    debt: referenceMetrics?.debt ?? null,
    netMargin: referenceMetrics?.revenue && referenceMetrics.netIncome !== null
      ? (referenceMetrics.netIncome / referenceMetrics.revenue) * 100
      : null
  };

  const annualFiling = redactedFilings.find((entry) => entry.filing_type === '10-K') ?? null;
  const [secDescription, yahooDescription, synthesizedDevelopments] = await Promise.all([
    getCompanyDescription(annualFiling),
    getYahooCompanyDescription(ticker),
    getRecentDevelopments(ticker, { filings: redactedFilings })
  ]);

  const description = yahooDescription ?? secDescription;
  const latestFilingSummary = latestFiling
    ? {
      accessionNumber: latestFiling.accession_number,
      filingDate: latestFiling.filing_date,
      filingType: latestFiling.filing_type,
      filingUrl: latestFiling.filing_url,
      submissionUrl: latestFiling.submission_url ?? null,
      summary: latestFiling.analysis?.text ?? latestFiling.analysis?.legacyInsights ?? null,
      hasAnalysis: Boolean(latestFiling.analysis?.text || latestFiling.analysis?.legacyInsights)
    }
    : null;
  const companyProfile = toCompanyProfile(secProfile, description);
  const valuationSnapshot = deriveValuationSnapshot({
    quote: liveQuote.value,
    sharesOutstanding: secProfile?.sharesOutstanding ?? null,
    revenue: keyMetrics.revenue,
    cash: keyMetrics.cash,
    debt: keyMetrics.debt,
    netIncome: keyMetrics.netIncome
  });
  const synthesis = await synthesizeCompanyOverview({
    ticker,
    companyName,
    description,
    memo: input.localInputs.memo,
    latestFilingSummary,
    recentAiReports: aiReports.slice(0, 5),
    recentDevelopments: synthesizedDevelopments.items
  });
  const recentDevelopments = {
    ...synthesizedDevelopments,
    weeklySnapshot: synthesis.weeklySnapshot,
    status: synthesizedDevelopments.items.length > 0
      ? synthesis.weeklySnapshot ? 'ready' : 'partial'
      : synthesis.weeklySnapshot ? 'partial' : 'unavailable'
  } as const;

  return {
    company: {
      ticker,
      companyName,
      sector: input.localInputs.watchlistItem?.sector ?? null,
      category: input.localInputs.watchlistItem?.category ?? null,
      tags: input.localInputs.watchlistItem?.tags ?? [],
      cik: latestFiling?.cik ?? null
    },
    quote: { value: liveQuote.value, stale: liveQuote.stale },
    position: input.localInputs.holding,
    priceHistory: { value: priceHistory.value, stale: priceHistory.stale },
    benchmarkHistory: { value: benchmarkHistory.value, stale: benchmarkHistory.stale },
    financials,
    filings: redactedFilings.slice(0, 20),
    aiReports,
    coverage: input.localInputs.watchlistItem
      ? {
        ...input.localInputs.watchlistItem,
        latest_filing_date: latestFiling?.filing_date ?? input.localInputs.watchlistItem.latest_filing_date ?? null
      }
      : null,
    journalPreview: input.localInputs.journalPreview,
    recentAiReports: aiReports.slice(0, 5),
    latestFilingSummary,
    keyMetrics,
    companyProfile,
    valuationSnapshot,
    bullBear: synthesis.bullBear,
    recentDevelopments
  };
}

type GetCompanyAnalysisPayloadOptions = {
  userId: string;
  ticker: string;
  refresh?: boolean;
  now?: Date;
};

type GetCompanyAnalysisPayloadDeps = {
  getLocalInputs?: (input: { userId: string; ticker: string }) => Promise<CompanyAnalysisLocalInputs>;
  getCachedOverview?: typeof getCompanyOverviewCache;
  upsertCachedOverview?: typeof upsertCompanyOverviewCache;
  buildOverview?: (input: {
    userId: string;
    ticker: string;
    localInputs: CompanyAnalysisLocalInputs;
  }) => Promise<CompanyAnalysis>;
};

export async function getCompanyAnalysisPayload(
  input: GetCompanyAnalysisPayloadOptions,
  deps?: GetCompanyAnalysisPayloadDeps
): Promise<CompanyAnalysis> {
  const ticker = input.ticker.trim().toUpperCase();
  const now = input.now ?? new Date();
  const localInputs = await (deps?.getLocalInputs ?? getCompanyAnalysisLocalInputs)({
    userId: input.userId,
    ticker
  });
  const sourceSignature = buildCompanyAnalysisSourceSignature({
    ticker,
    localInputs
  });
  const cached = await (deps?.getCachedOverview ?? getCompanyOverviewCache)({
    userId: input.userId,
    ticker
  });

  if (cached && isCompanyOverviewCacheFresh({
    updatedAt: cached.updated_at,
    sourceSignature: cached.source_signature,
    expectedSourceSignature: sourceSignature,
    cacheVersion: cached.cache_version,
    refresh: input.refresh,
    now
  })) {
    return cached.payload;
  }

  const analysis = await (deps?.buildOverview ?? buildCompanyAnalysisPayload)({
    userId: input.userId,
    ticker,
    localInputs
  });

  await (deps?.upsertCachedOverview ?? upsertCompanyOverviewCache)({
    userId: input.userId,
    ticker,
    sourceSignature,
    payload: analysis
  });

  return analysis;
}

export const __companyAnalysisInternals = {
  COMPANY_OVERVIEW_CACHE_TTL_MS,
  buildCompanyAnalysisPayload,
  buildCompanyAnalysisSourceSignature,
  getCompanyAnalysisLocalInputs,
  isCompanyOverviewCacheFresh,
  withFinancialMetricsPolicy
};