import { api } from '@/lib/api'

export type FinanceReportType =
  | 'TrialBalance'
  | 'GeneralLedger'
  | 'ProfitAndLoss'
  | 'BalanceSheet'
  | 'CashFlow'
  | 'BudgetVsActual'
  | 'TaxSummary'

export interface FinanceReportParams {
  asOfDate?: string
  periodStart?: string
  periodEnd?: string
  accountCode?: string
  budgetId?: number
}

export type FileFormat = 'Pdf' | 'Csv'

const cleanParams = (params: FinanceReportParams) =>
  Object.fromEntries(Object.entries(params).filter(([, v]) => v !== undefined && v !== ''))

// Reports come from the General Ledger service through the Distribution backend (/reports/finance/{type}).
export interface GlAccountOption {
  accountCode: string
  accountName: string
}

export const financeReports = {
  /** Active GL accounts for the account dropdown. */
  accounts: () => api.get<GlAccountOption[]>('/reports/finance/accounts').then(r => r.data),

  get: (type: FinanceReportType, params: FinanceReportParams) =>
    api.get<unknown>(`/reports/finance/${type}`, { params: cleanParams(params) }).then(r => r.data),

  /** Downloads the GL-rendered PDF or CSV and hands it to the browser. */
  async download(type: FinanceReportType, params: FinanceReportParams, format: FileFormat) {
    const res = await api.get<Blob>(`/reports/finance/${type}`, {
      params: { ...cleanParams(params), outputFormat: format },
      responseType: 'blob',
    })
    const disposition = String(res.headers['content-disposition'] ?? '')
    const name = /filename\*?=(?:UTF-8'')?"?([^";]+)"?/i.exec(disposition)?.[1] ?? `${type}.${format.toLowerCase()}`
    const url = URL.createObjectURL(res.data)
    const a = document.createElement('a')
    a.href = url
    a.download = decodeURIComponent(name)
    a.click()
    URL.revokeObjectURL(url)
  },
}

export interface GlStatus {
  glReachable: boolean
  setupDone: boolean
  openingBalancePosted: boolean
  closedYears: number[]
  mapping: Record<string, string | null>
  posted: number
  failed: number
}

export interface GlPostingRow {
  id: string
  event: string
  sourceId: string
  reference: string
  status: 'Pending' | 'Posted' | 'Failed'
  glJournalNo: string | null
  error: string | null
  attempts: number
  lastAttemptAt: string | null
  createdAt: string
}

export interface OpeningBalanceLine {
  /** A key such as 'Inventory' or 'ShareCapital', or 'BankAccount' together with bankAccountId. */
  account: string
  bankAccountId?: string
  /** The account's normal balance (>= 0). Debit/credit side is decided by the backend. */
  amount: number
}

export interface YearEndPreview {
  year: number
  startDate: string
  endDate: string
  totalIncome: number
  totalExpenses: number
  netProfit: number
  closable: boolean
  reason: string | null
  alreadyClosed: boolean
}

export const generalLedger = {
  yearEndPreview: (year: number) =>
    api.get<YearEndPreview>('/gl/year-end/preview', { params: { year } }).then(r => r.data),
  closeYear: (year: number) =>
    api.post<{ year: number; glJournalNo: string | null; netProfit: number; periodsLocked: number }>('/gl/year-end/close', { year }).then(r => r.data),
  postOpeningBalances: (date: string, narration: string, lines: OpeningBalanceLine[]) =>
    api.post<{ status: string; glJournalNo: string | null }>('/gl/opening-balances', { date, narration, lines }).then(r => r.data),
  status: () => api.get<GlStatus>('/gl/status').then(r => r.data),
  setup: (year?: number) => api.post<{ done: boolean; actions: string[] }>('/gl/setup', { year }).then(r => r.data),
  postings: (status?: GlPostingRow['status']) =>
    api.get<GlPostingRow[]>('/gl/postings', { params: { status } }).then(r => r.data),
  retry: () => api.post<{ posted: number }>('/gl/postings/retry').then(r => r.data),
}