import * as plugins from './plugins.js';
import { ChartOfAccounts } from './skr.classes.chartofaccounts.js';
import { Ledger } from './skr.classes.ledger.js';
import { Reports } from './skr.classes.reports.js';
import { Account } from './skr.classes.account.js';
import { Transaction } from './skr.classes.transaction.js';
import { JournalEntry } from './skr.classes.journalentry.js';
import type {
  IDatabaseConfig,
  TSKRType,
  IAccountData,
  IAccountFilter,
  ITransactionData,
  ITransactionFilter,
  IJournalEntry,
  IReportParams,
  ITrialBalanceReport,
  IIncomeStatement,
  IBalanceSheet,
} from './skr.types.js';

/**
 * Main API class for SKR accounting operations
 */
export class SkrApi {
  private chartOfAccounts: ChartOfAccounts;
  private ledger: Ledger | null = null;
  private reports: Reports | null = null;
  private logger: plugins.smartlog.Smartlog;
  private initialized: boolean = false;
  private currentSKRType: TSKRType | null = null;

  constructor(private config: IDatabaseConfig) {
    this.chartOfAccounts = new ChartOfAccounts(config);
    this.logger = new plugins.smartlog.Smartlog({
      logContext: {
        company: 'fin.cx',
        companyunit: 'skr',
        containerName: 'SkrApi',
        environment: 'local',
        runtime: 'node',
        zone: 'local',
      },
    });
  }

  /**
   * Initialize the API with specified SKR type
   */
  public async initialize(skrType: TSKRType): Promise<void> {
    this.logger.log('info', `Initializing SKR API with ${skrType}`);

    // Initialize chart of accounts
    if (skrType === 'SKR03') {
      await this.chartOfAccounts.initializeSKR03();
    } else if (skrType === 'SKR04') {
      await this.chartOfAccounts.initializeSKR04();
    } else {
      throw new Error(`Invalid SKR type: ${skrType}`);
    }

    this.currentSKRType = skrType;
    this.ledger = new Ledger(skrType);
    this.reports = new Reports(skrType);
    this.initialized = true;

    this.logger.log('info', 'SKR API initialized successfully');
  }

  /**
   * Ensure API is initialized
   */
  private ensureInitialized(): void {
    if (!this.initialized || !this.currentSKRType) {
      throw new Error('API not initialized. Call initialize() first.');
    }
  }

  // ========== Account Management ==========

  /**
   * Create a new account
   */
  public async createAccount(
    accountData: Partial<IAccountData>,
  ): Promise<Account> {
    this.ensureInitialized();
    return await this.chartOfAccounts.createCustomAccount(accountData);
  }

  /**
   * Get account by number
   */
  public async getAccount(accountNumber: string): Promise<Account | null> {
    this.ensureInitialized();
    return await this.chartOfAccounts.getAccountByNumber(accountNumber);
  }

  /**
   * Update an account
   */
  public async updateAccount(
    accountNumber: string,
    updates: Partial<IAccountData>,
  ): Promise<Account> {
    this.ensureInitialized();
    return await this.chartOfAccounts.updateAccount(accountNumber, updates);
  }

  /**
   * Delete an account
   */
  public async deleteAccount(accountNumber: string): Promise<void> {
    this.ensureInitialized();
    await this.chartOfAccounts.deleteAccount(accountNumber);
  }

  /**
   * List accounts with optional filter
   */
  public async listAccounts(filter?: IAccountFilter): Promise<Account[]> {
    this.ensureInitialized();
    return await this.chartOfAccounts.getAllAccounts(filter);
  }

  /**
   * Search accounts by term
   */
  public async searchAccounts(searchTerm: string): Promise<Account[]> {
    this.ensureInitialized();
    return await this.chartOfAccounts.searchAccounts(searchTerm);
  }

  /**
   * Get accounts by class
   */
  public async getAccountsByClass(accountClass: number): Promise<Account[]> {
    this.ensureInitialized();
    return await this.chartOfAccounts.getAccountsByClass(accountClass);
  }

  /**
   * Get accounts by type
   */
  public async getAccountsByType(
    accountType: IAccountData['accountType'],
  ): Promise<Account[]> {
    this.ensureInitialized();
    return await this.chartOfAccounts.getAccountsByType(accountType);
  }

  // ========== Transaction Management ==========

  /**
   * Post a simple transaction
   */
  public async postTransaction(
    transactionData: ITransactionData,
  ): Promise<Transaction> {
    this.ensureInitialized();
    return await this.chartOfAccounts.postTransaction(transactionData);
  }

  /**
   * Post a journal entry
   */
  public async postJournalEntry(
    journalData: IJournalEntry,
  ): Promise<JournalEntry> {
    this.ensureInitialized();
    return await this.chartOfAccounts.postJournalEntry(journalData);
  }

  /**
   * Get transaction by ID
   */
  public async getTransaction(
    transactionId: string,
  ): Promise<Transaction | null> {
    this.ensureInitialized();
    return await Transaction.getTransactionById(transactionId);
  }

  /**
   * List transactions with optional filter
   */
  public async listTransactions(
    filter?: ITransactionFilter,
  ): Promise<Transaction[]> {
    this.ensureInitialized();
    return await this.chartOfAccounts.getTransactions(filter);
  }

  /**
   * Get transactions for specific account
   */
  public async getAccountTransactions(
    accountNumber: string,
  ): Promise<Transaction[]> {
    this.ensureInitialized();
    return await this.chartOfAccounts.getAccountTransactions(accountNumber);
  }

  /**
   * Reverse a transaction
   */
  public async reverseTransaction(transactionId: string): Promise<Transaction> {
    this.ensureInitialized();
    return await this.chartOfAccounts.reverseTransaction(transactionId);
  }

  /**
   * Reverse a journal entry
   */
  public async reverseJournalEntry(journalId: string): Promise<JournalEntry> {
    this.ensureInitialized();
    if (!this.ledger) throw new Error('Ledger not initialized');
    return await this.ledger.reverseJournalEntry(journalId);
  }

  // ========== Reporting ==========

  /**
   * Generate trial balance
   */
  public async generateTrialBalance(
    params?: IReportParams,
  ): Promise<ITrialBalanceReport> {
    this.ensureInitialized();
    if (!this.reports) throw new Error('Reports not initialized');
    return await this.reports.getTrialBalance(params);
  }

  /**
   * Generate income statement
   */
  public async generateIncomeStatement(
    params?: IReportParams,
  ): Promise<IIncomeStatement> {
    this.ensureInitialized();
    if (!this.reports) throw new Error('Reports not initialized');
    return await this.reports.getIncomeStatement(params);
  }

  /**
   * Generate balance sheet
   */
  public async generateBalanceSheet(
    params?: IReportParams,
  ): Promise<IBalanceSheet> {
    this.ensureInitialized();
    if (!this.reports) throw new Error('Reports not initialized');
    return await this.reports.getBalanceSheet(params);
  }

  /**
   * Generate general ledger
   */
  public async generateGeneralLedger(params?: IReportParams): Promise<any> {
    this.ensureInitialized();
    if (!this.reports) throw new Error('Reports not initialized');
    return await this.reports.getGeneralLedger(params);
  }

  /**
   * Generate cash flow statement
   */
  public async generateCashFlowStatement(params?: IReportParams): Promise<any> {
    this.ensureInitialized();
    if (!this.reports) throw new Error('Reports not initialized');
    return await this.reports.getCashFlowStatement(params);
  }

  /**
   * Export report to CSV
   */
  public async exportReportToCSV(
    reportType: 'trial_balance' | 'income_statement' | 'balance_sheet',
    params?: IReportParams,
  ): Promise<string> {
    this.ensureInitialized();
    if (!this.reports) throw new Error('Reports not initialized');
    return await this.reports.exportToCSV(reportType, params);
  }

  /**
   * Export to DATEV format
   */
  public async exportToDATEV(params?: IReportParams): Promise<string> {
    this.ensureInitialized();
    if (!this.reports) throw new Error('Reports not initialized');
    return await this.reports.exportToDATEV(params);
  }

  // ========== Period Management ==========

  /**
   * Close accounting period
   */
  public async closePeriod(
    period: string,
    closingAccountNumber?: string,
  ): Promise<JournalEntry[]> {
    this.ensureInitialized();
    if (!this.ledger) throw new Error('Ledger not initialized');
    return await this.ledger.closeAccountingPeriod(
      period,
      closingAccountNumber,
    );
  }

  /**
   * Get account balance
   */
  public async getAccountBalance(
    accountNumber: string,
    asOfDate?: Date,
  ): Promise<any> {
    this.ensureInitialized();
    if (!this.ledger) throw new Error('Ledger not initialized');
    return await this.ledger.getAccountBalance(accountNumber, asOfDate);
  }

  /**
   * Recalculate all account balances
   */
  public async recalculateBalances(): Promise<void> {
    this.ensureInitialized();
    if (!this.ledger) throw new Error('Ledger not initialized');
    await this.ledger.recalculateAllBalances();
  }

  // ========== Import/Export ==========

  /**
   * Import accounts from CSV
   */
  public async importAccountsFromCSV(csvContent: string): Promise<number> {
    this.ensureInitialized();
    return await this.chartOfAccounts.importAccountsFromCSV(csvContent);
  }

  /**
   * Export accounts to CSV
   */
  public async exportAccountsToCSV(): Promise<string> {
    this.ensureInitialized();
    return await this.chartOfAccounts.exportAccountsToCSV();
  }

  // ========== Utility Methods ==========

  /**
   * Get current SKR type
   */
  public getSKRType(): TSKRType | null {
    return this.currentSKRType;
  }

  /**
   * Get account class description
   */
  public getAccountClassDescription(accountClass: number): string {
    this.ensureInitialized();
    return this.chartOfAccounts.getAccountClassDescription(accountClass);
  }

  /**
   * Validate double-entry rules
   */
  public validateDoubleEntry(
    debitAmount: number,
    creditAmount: number,
  ): boolean {
    if (!this.ledger) throw new Error('Ledger not initialized');
    return this.ledger.validateDoubleEntry(debitAmount, creditAmount);
  }

  /**
   * Get unbalanced transactions (for audit)
   */
  public async getUnbalancedTransactions(): Promise<Transaction[]> {
    this.ensureInitialized();
    if (!this.ledger) throw new Error('Ledger not initialized');
    return await this.ledger.getUnbalancedTransactions();
  }

  /**
   * Close the API and database connection
   */
  public async close(): Promise<void> {
    await this.chartOfAccounts.close();
    this.initialized = false;
    this.currentSKRType = null;
    this.ledger = null;
    this.reports = null;
    this.logger.log('info', 'SKR API closed');
  }

  // ========== Batch Operations ==========

  /**
   * Post multiple transactions
   */
  public async postBatchTransactions(
    transactions: ITransactionData[],
  ): Promise<Transaction[]> {
    this.ensureInitialized();

    const results: Transaction[] = [];
    const errors: Array<{ index: number; error: string }> = [];

    for (let i = 0; i < transactions.length; i++) {
      try {
        const transaction = await this.postTransaction(transactions[i]);
        results.push(transaction);
      } catch (error) {
        errors.push({ index: i, error: error.message });
      }
    }

    if (errors.length > 0) {
      this.logger.log(
        'warn',
        `Batch transaction posting completed with ${errors.length} errors`,
      );
      throw new Error(
        `Batch posting failed for ${errors.length} transactions: ${JSON.stringify(errors)}`,
      );
    }

    return results;
  }

  /**
   * Create multiple accounts
   */
  public async createBatchAccounts(
    accounts: IAccountData[],
  ): Promise<Account[]> {
    this.ensureInitialized();

    const results: Account[] = [];
    const errors: Array<{ index: number; error: string }> = [];

    for (let i = 0; i < accounts.length; i++) {
      try {
        const account = await this.createAccount(accounts[i]);
        results.push(account);
      } catch (error) {
        errors.push({ index: i, error: error.message });
      }
    }

    if (errors.length > 0) {
      this.logger.log(
        'warn',
        `Batch account creation completed with ${errors.length} errors`,
      );
      throw new Error(
        `Batch creation failed for ${errors.length} accounts: ${JSON.stringify(errors)}`,
      );
    }

    return results;
  }

  // ========== Pagination Support ==========

  /**
   * Get paginated accounts
   */
  public async getAccountsPaginated(
    page: number = 1,
    pageSize: number = 50,
    filter?: IAccountFilter,
  ): Promise<{
    data: Account[];
    total: number;
    page: number;
    pageSize: number;
    totalPages: number;
  }> {
    this.ensureInitialized();

    const allAccounts = await this.listAccounts(filter);
    const total = allAccounts.length;
    const totalPages = Math.ceil(total / pageSize);
    const start = (page - 1) * pageSize;
    const end = start + pageSize;
    const data = allAccounts.slice(start, end);

    return {
      data,
      total,
      page,
      pageSize,
      totalPages,
    };
  }

  /**
   * Get paginated transactions
   */
  public async getTransactionsPaginated(
    page: number = 1,
    pageSize: number = 50,
    filter?: ITransactionFilter,
  ): Promise<{
    data: Transaction[];
    total: number;
    page: number;
    pageSize: number;
    totalPages: number;
  }> {
    this.ensureInitialized();

    const allTransactions = await this.listTransactions(filter);
    const total = allTransactions.length;
    const totalPages = Math.ceil(total / pageSize);
    const start = (page - 1) * pageSize;
    const end = start + pageSize;
    const data = allTransactions.slice(start, end);

    return {
      data,
      total,
      page,
      pageSize,
      totalPages,
    };
  }
}