// Copyright 2025 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

import {
  resolveValue,
  identifyAuthRequirements,
} from '../src/toolbox_core/utils';

describe('resolveValue', () => {
  // Test cases for literal values (non-functions)
  describe('when given a literal value', () => {
    test('should return a resolved promise with the same string value', async () => {
      const value = 'a literal string';
      await expect(resolveValue(value)).resolves.toBe(value);
    });

    test('should return a resolved promise with the same number value', async () => {
      const value = 123;
      await expect(resolveValue(value)).resolves.toBe(value);
    });

    test('should return a resolved promise with the same boolean value', async () => {
      const value = false;
      await expect(resolveValue(value)).resolves.toBe(value);
    });

    test('should return a resolved promise with a null value', async () => {
      const value = null;
      await expect(resolveValue(value)).resolves.toBeNull();
    });

    test('should return a resolved promise with an undefined value', async () => {
      const value = undefined;
      await expect(resolveValue(value)).resolves.toBeUndefined();
    });

    test('should return a resolved promise with the same object', async () => {
      const value = {key: 'value', nested: {a: 1}};
      // Use .toEqual for deep object comparison
      await expect(resolveValue(value)).resolves.toEqual(value);
    });
  });

  // Test cases for synchronous functions
  describe('when given a synchronous function', () => {
    test('should execute the function and resolve with its return value', async () => {
      const syncFunction = () => 'result from sync function';
      await expect(resolveValue(syncFunction)).resolves.toBe(
        'result from sync function',
      );
    });

    test('should execute a function returning an object and resolve with that object', async () => {
      const obj = {data: 'test'};
      const syncFunction = () => obj;
      await expect(resolveValue(syncFunction)).resolves.toEqual(obj);
    });

    test('should return a rejected promise if the synchronous function throws an error', async () => {
      const error = new Error('Something went wrong');
      const failingSyncFunction = () => {
        throw error;
      };
      // .rejects checks for promise rejection, .toThrow checks the error itself
      await expect(resolveValue(failingSyncFunction)).rejects.toThrow(error);
    });
  });

  // Test cases for asynchronous (promise-returning) functions
  describe('when given an asynchronous function', () => {
    test('should await an async function and resolve with its value', async () => {
      const asyncFunction = async () => 'result from async function';
      await expect(resolveValue(asyncFunction)).resolves.toBe(
        'result from async function',
      );
    });

    test('should await a function returning a Promise and resolve with its value', async () => {
      const promiseFunction = () => Promise.resolve({data: 'from promise'});
      await expect(resolveValue(promiseFunction)).resolves.toEqual({
        data: 'from promise',
      });
    });

    test('should correctly handle a delay in an async function', async () => {
      const delayedAsyncFunction = async () => {
        return new Promise(resolve => {
          setTimeout(() => resolve('delayed result'), 20);
        });
      };
      await expect(resolveValue(delayedAsyncFunction)).resolves.toBe(
        'delayed result',
      );
    });

    test('should return a rejected promise if the async function rejects', async () => {
      const error = new Error('Async operation failed');
      const rejectingAsyncFunction = async () => {
        throw error;
      };
      await expect(resolveValue(rejectingAsyncFunction)).rejects.toThrow(error);
    });

    test('should return a rejected promise if the function returns a rejected promise', async () => {
      const error = new Error('Explicit rejection');
      const rejectingPromiseFunction = () => Promise.reject(error);
      await expect(resolveValue(rejectingPromiseFunction)).rejects.toThrow(
        error,
      );
    });
  });
});

describe('identifyAuthRequirements', () => {
  it('should return empty requirements and used services if all are met', () => {
    const reqAuthnParams = {param1: ['serviceA']};
    const reqAuthzTokens = ['serviceB'];
    const authServiceNames = ['serviceA', 'serviceB'];
    const [remainingAuthnParams, remainingAuthzTokens, usedServices] =
      identifyAuthRequirements(
        reqAuthnParams,
        reqAuthzTokens,
        authServiceNames,
      );
    expect(remainingAuthnParams).toEqual({});
    expect(remainingAuthzTokens).toEqual([]);
    expect(usedServices).toEqual(new Set(['serviceA', 'serviceB']));
  });

  it('should return remaining requirements if some are not met', () => {
    const reqAuthnParams = {param1: ['serviceA'], param2: ['serviceC']};
    const reqAuthzTokens = ['serviceB', 'serviceD'];
    const authServiceNames = ['serviceA', 'serviceB'];
    const [remainingAuthnParams, remainingAuthzTokens, usedServices] =
      identifyAuthRequirements(
        reqAuthnParams,
        reqAuthzTokens,
        authServiceNames,
      );
    expect(remainingAuthnParams).toEqual({param2: ['serviceC']});
    expect(remainingAuthzTokens).toEqual(['serviceD']);
    expect(usedServices).toEqual(new Set(['serviceA', 'serviceB']));
  });

  it('should handle no initial requirements', () => {
    const reqAuthnParams = {};
    const reqAuthzTokens: string[] = [];
    const authServiceNames = ['serviceA', 'serviceB'];
    const [remainingAuthnParams, remainingAuthzTokens, usedServices] =
      identifyAuthRequirements(
        reqAuthnParams,
        reqAuthzTokens,
        authServiceNames,
      );
    expect(remainingAuthnParams).toEqual({});
    expect(remainingAuthzTokens).toEqual([]);
    expect(usedServices).toEqual(new Set());
  });

  it('should handle no available auth services', () => {
    const reqAuthnParams = {param1: ['serviceA']};
    const reqAuthzTokens = ['serviceB'];
    const authServiceNames: string[] = [];
    const [remainingAuthnParams, remainingAuthzTokens, usedServices] =
      identifyAuthRequirements(
        reqAuthnParams,
        reqAuthzTokens,
        authServiceNames,
      );
    expect(remainingAuthnParams).toEqual({param1: ['serviceA']});
    expect(remainingAuthzTokens).toEqual(['serviceB']);
    expect(usedServices).toEqual(new Set());
  });

  it('should correctly identify used services even if some requirements remain', () => {
    const reqAuthnParams = {param1: ['serviceA', 'serviceX']};
    const reqAuthzTokens = ['serviceB', 'serviceY'];
    const authServiceNames = ['serviceA', 'serviceB'];
    const [remainingAuthnParams, remainingAuthzTokens, usedServices] =
      identifyAuthRequirements(
        reqAuthnParams,
        reqAuthzTokens,
        authServiceNames,
      );
    expect(remainingAuthnParams).toEqual({});
    expect(remainingAuthzTokens).toEqual(['serviceY']);
    expect(usedServices).toEqual(new Set(['serviceA', 'serviceB']));
  });

  it('should handle cases where a param requires multiple services and only some are met', () => {
    const reqAuthnParams = {param1: ['serviceA', 'serviceX']};
    const reqAuthzTokens: string[] = [];
    const authServiceNames = ['serviceA'];
    const [remainingAuthnParams, remainingAuthzTokens, usedServices] =
      identifyAuthRequirements(
        reqAuthnParams,
        reqAuthzTokens,
        authServiceNames,
      );
    expect(remainingAuthnParams).toEqual({});
    expect(remainingAuthzTokens).toEqual([]);
    expect(usedServices).toEqual(new Set(['serviceA']));
  });
});