/**
 * Generated by the Lango developer portal. Do not edit by hand.
 * Group: payments (Payments)
 * APIs: Collect v1.2.0, Payouts v1.0.3, Ledger v2.1.0
 * Generated: 2026-09-28T11:00:55.868Z
 */

export class LangoApiError extends Error {
  status: number;
  error: string;
  requestId?: string;
  constructor(status: number, error: string, message: string, requestId?: string) {
    super(message);
    this.name = "LangoApiError";
    this.status = status;
    this.error = error;
    this.requestId = requestId;
  }
}

export interface CreatePushRequest {
  /** The till or paybill number receiving the money. */
  shortCode: string;
  /** Whole currency units. In the sandbox, 1, 2 and 3 trigger failure scenarios. */
  amount: number;
  currency: "KES" | "TZS" | "UGX";
  /** Customer's number in international format, no plus sign. */
  phoneNumber: string;
  /** Your own reference. Shown to the customer and returned in the callback. */
  reference: string;
  description?: string;
  /** Where the final result is posted. */
  callbackUrl: string;
}

export interface SendPayoutRequest {
  /** Whole currency units. In the sandbox, 1 triggers the low-float scenario. */
  amount: number;
  currency: "KES" | "TZS" | "UGX";
  destination: { type: "mobile" | "bank"; phoneNumber?: string; bankCode?: string; accountNumber?: string };
  /** Unique per payout. Reusing one returns 409. */
  reference: string;
  reason?: "Salary" | "Supplier" | "Refund" | "Commission" | "Other";
  callbackUrl: string;
}

export interface ReverseTransactionRequest {
  reason: string;
  callbackUrl: string;
}

export class PaymentsClient {
  private consumerKey: string;
  private consumerSecret: string;
  private baseUrl: string;
  private token: string | null = null;
  private tokenExpiresAt = 0;

  constructor(consumerKey: string, consumerSecret: string, baseUrl: string) {
    this.consumerKey = consumerKey;
    this.consumerSecret = consumerSecret;
    this.baseUrl = baseUrl.replace(/\/+$/, "");
  }

  private async getToken(): Promise<string> {
    if (this.token && Date.now() < this.tokenExpiresAt) return this.token;
    const basic = btoa(`${this.consumerKey}:${this.consumerSecret}`);
    const res = await fetch(`${this.baseUrl}/oauth/v1/token`, {
      method: "POST",
      headers: { authorization: `Basic ${basic}`, "content-type": "application/x-www-form-urlencoded" },
      body: "grant_type=client_credentials",
    });
    const data = (await res.json().catch(() => undefined)) as
      | { access_token?: string; expires_in?: number; error?: string; message?: string; requestId?: string }
      | undefined;
    if (!res.ok || !data?.access_token) {
      throw new LangoApiError(res.status, data?.error ?? "TOKEN_ERROR", data?.message ?? "Could not get a sandbox token.", data?.requestId);
    }
    this.token = data.access_token;
    this.tokenExpiresAt = Date.now() + ((data.expires_in ?? 3600) - 60) * 1000;
    return this.token;
  }

  private async request(
    method: string,
    path: string,
    query: Record<string, string | number | boolean | undefined> | undefined,
    body: unknown,
  ): Promise<unknown> {
    const token = await this.getToken();
    const parts = Object.entries(query ?? {})
      .filter(([, v]) => v !== undefined)
      .map(([k, v]) => `${encodeURIComponent(k)}=${encodeURIComponent(String(v))}`);
    const url = this.baseUrl + path + (parts.length ? `?${parts.join("&")}` : "");
    const res = await fetch(url, {
      method,
      headers: {
        authorization: `Bearer ${token}`,
        ...(body !== undefined ? { "content-type": "application/json" } : {}),
      },
      body: body !== undefined ? JSON.stringify(body) : undefined,
    });
    const data = await res.json().catch(() => undefined);
    if (!res.ok) {
      const d = data as { error?: string; message?: string; requestId?: string } | undefined;
      throw new LangoApiError(res.status, d?.error ?? "REQUEST_FAILED", d?.message ?? res.statusText, d?.requestId);
    }
    return data;
  }

  /** Send a payment prompt */
  async createPush(body: CreatePushRequest): Promise<unknown> {
    return this.request("POST", `/collect/v1/push`, undefined, body);
  }

  /** Check a payment prompt */
  async getPush(params: { checkoutId: string }): Promise<unknown> {
    return this.request("GET", `/collect/v1/push/${encodeURIComponent(String(params.checkoutId))}`, undefined, undefined);
  }

  /** Send a payout */
  async sendPayout(body: SendPayoutRequest): Promise<unknown> {
    return this.request("POST", `/payouts/v1/send`, undefined, body);
  }

  /** Check a payout */
  async getPayout(params: { payoutId: string }): Promise<unknown> {
    return this.request("GET", `/payouts/v1/${encodeURIComponent(String(params.payoutId))}`, undefined, undefined);
  }

  /** Look up a transaction */
  async getTransaction(params: { transactionId: string }): Promise<unknown> {
    return this.request("GET", `/ledger/v2/transactions/${encodeURIComponent(String(params.transactionId))}`, undefined, undefined);
  }

  /** Reverse a transaction */
  async reverseTransaction(params: { transactionId: string }, body: ReverseTransactionRequest): Promise<unknown> {
    return this.request("POST", `/ledger/v2/transactions/${encodeURIComponent(String(params.transactionId))}/reversal`, undefined, body);
  }

  /** Read your balances */
  async getBalance(params: { shortCode: string }): Promise<unknown> {
    return this.request("GET", `/ledger/v2/balance`, { shortCode: params.shortCode }, undefined);
  }
}