import {
  render,
  waitFor,
  screen,
  fireEvent,
  waitForElementToBeRemoved,
  within,
  Matcher,
  getByRole,
} from '@testing-library/react';
import { merge, uniqueId } from 'lodash';
import React from 'react';
import { DeepPartial } from 'react-hook-form';
import { Provider } from 'react-redux';
import { Observable } from 'rxjs';
import { MockDataSourceApi } from 'test/mocks/datasource_srv';
import { getGrafanaContextMock } from 'test/mocks/getGrafanaContextMock';

import { DataSourcePluginMeta } from '@grafana/data';
import {
  BackendSrv,
  FetchError,
  FetchResponse,
  setDataSourceSrv,
  BackendSrvRequest,
  reportInteraction,
} from '@grafana/runtime';
import { GrafanaContext } from 'app/core/context/GrafanaContext';
import { contextSrv } from 'app/core/services/context_srv';
import { configureStore } from 'app/store/configureStore';

import { mockDataSource, MockDataSourceSrv } from '../alerting/unified/mocks';

import CorrelationsPage from './CorrelationsPage';
import { Correlation, CreateCorrelationParams } from './types';

function createFetchResponse<T>(overrides?: DeepPartial<FetchResponse>): FetchResponse<T> {
  return merge(
    {
      data: undefined,
      status: 200,
      url: '',
      config: { url: '' },
      type: 'basic',
      statusText: 'Ok',
      redirected: false,
      headers: {} as unknown as Headers,
      ok: true,
    },
    overrides
  );
}

function createFetchError(overrides?: DeepPartial<FetchError>): FetchError {
  return merge(
    createFetchResponse(),
    {
      status: 500,
      statusText: 'Internal Server Error',
      ok: false,
    },
    overrides
  );
}

const renderWithContext = async (
  datasources: ConstructorParameters<typeof MockDataSourceSrv>[0] = {},
  correlations: Correlation[] = []
) => {
  const backend = {
    delete: async (url: string) => {
      const matches = url.match(
        /^\/api\/datasources\/uid\/(?<dsUid>[a-zA-Z0-9]+)\/correlations\/(?<correlationUid>[a-zA-Z0-9]+)$/
      );

      if (matches?.groups) {
        const { dsUid, correlationUid } = matches.groups;
        correlations = correlations.filter((c) => c.uid !== correlationUid || c.sourceUID !== dsUid);
        return createFetchResponse({
          data: {
            message: 'Correlation deleted',
          },
        });
      }

      throw createFetchError({
        data: {
          message: 'Correlation not found',
        },
        status: 404,
      });
    },
    post: async (url: string, data: Omit<CreateCorrelationParams, 'sourceUID'>) => {
      const matches = url.match(/^\/api\/datasources\/uid\/(?<sourceUID>[a-zA-Z0-9]+)\/correlations$/);
      if (matches?.groups) {
        const { sourceUID } = matches.groups;
        const correlation = { sourceUID, ...data, uid: uniqueId() };
        correlations.push(correlation);
        return correlation;
      }

      throw createFetchError({
        status: 404,
        data: {
          message: 'Source datasource not found',
        },
      });
    },
    patch: async (url: string, data: Omit<CreateCorrelationParams, 'sourceUID'>) => {
      const matches = url.match(
        /^\/api\/datasources\/uid\/(?<sourceUID>[a-zA-Z0-9]+)\/correlations\/(?<correlationUid>[a-zA-Z0-9]+)$/
      );
      if (matches?.groups) {
        const { sourceUID, correlationUid } = matches.groups;
        correlations = correlations.map((c) => {
          if (c.uid === correlationUid && sourceUID === c.sourceUID) {
            return { ...c, ...data };
          }
          return c;
        });
        return createFetchResponse({
          data: { sourceUID, ...data },
        });
      }

      throw createFetchError({
        data: { message: 'either correlation uid or source id not found' },
        status: 404,
      });
    },
    fetch: (options: BackendSrvRequest) => {
      return new Observable((s) => {
        s.next(merge(createFetchResponse({ url: options.url, data: correlations })));

        s.complete();
      });
    },
  } as unknown as BackendSrv;
  const grafanaContext = getGrafanaContextMock({ backend });

  const dsServer = new MockDataSourceSrv(datasources);
  dsServer.get = (name: string) => {
    const dsApi = new MockDataSourceApi(name);
    dsApi.components = {
      QueryEditor: () => <>{name} query editor</>,
    };
    return Promise.resolve(dsApi);
  };

  setDataSourceSrv(dsServer);

  const renderResult = render(
    <Provider store={configureStore({})}>
      <GrafanaContext.Provider value={grafanaContext}>
        <CorrelationsPage />
      </GrafanaContext.Provider>
    </Provider>,
    {
      queries: {
        /**
         * Gets all the rows in the table having the given text in the given column
         */
        queryRowsByCellValue: (
          container: HTMLElement,
          columnName: Matcher,
          textValue: Matcher
        ): HTMLTableRowElement[] => {
          const table = within(container).getByRole('table');
          const headers = within(table).getAllByRole('columnheader');
          const headerIndex = headers.findIndex((h) => {
            return within(h).queryByText(columnName);
          });

          // the first rowgroup is the header
          const tableBody = within(table).getAllByRole('rowgroup')[1];

          return within(tableBody)
            .getAllByRole<HTMLTableRowElement>('row')
            .filter((row) => {
              const rowCells = within(row).getAllByRole('cell');
              const cell = rowCells[headerIndex];
              return within(cell).queryByText(textValue);
            });
        },
        /**
         * Gets all the cells in the table for the given column name
         */
        queryCellsByColumnName: (container: HTMLElement, columnName: Matcher) => {
          const table = within(container).getByRole('table');
          const headers = within(table).getAllByRole('columnheader');
          const headerIndex = headers.findIndex((h) => {
            return within(h).queryByText(columnName);
          });
          const tbody = table.querySelector('tbody');
          if (!tbody) {
            return [];
          }
          return within(tbody)
            .getAllByRole('row')
            .map((r) => {
              const cells = within(r).getAllByRole<HTMLTableCellElement>('cell');
              return cells[headerIndex];
            });
        },
        /**
         * Gets the table header cell matching the given name
         */
        getHeaderByName: (container: HTMLElement, columnName: Matcher): HTMLTableCellElement => {
          const table = within(container).getByRole('table');
          const headers = within(table).getAllByRole<HTMLTableCellElement>('columnheader');
          const header = headers.find((h) => {
            return within(h).queryByText(columnName);
          });
          if (!header) {
            throw new Error(`Could not find header with name ${columnName}`);
          }
          return header;
        },
      },
    }
  );

  await waitFor(() => {
    expect(screen.queryByText('Loading')).not.toBeInTheDocument();
  });

  return renderResult;
};

jest.mock('app/core/services/context_srv');

const mocks = {
  contextSrv: jest.mocked(contextSrv),
  reportInteraction: jest.fn(),
};

jest.mock('@grafana/runtime', () => ({
  ...jest.requireActual('@grafana/runtime'),
  reportInteraction: (...args: Parameters<typeof reportInteraction>) => {
    mocks.reportInteraction(...args);
  },
}));

beforeAll(() => {
  mocks.contextSrv.hasPermission.mockImplementation(() => true);
});

afterAll(() => {
  jest.restoreAllMocks();
});

describe('CorrelationsPage', () => {
  describe('With no correlations', () => {
    beforeEach(async () => {
      await renderWithContext({
        loki: mockDataSource(
          {
            uid: 'loki',
            name: 'loki',
            readOnly: false,
            jsonData: {},
            access: 'direct',
            type: 'datasource',
          },
          { logs: true }
        ),
        prometheus: mockDataSource(
          {
            uid: 'prometheus',
            name: 'prometheus',
            readOnly: false,
            jsonData: {},
            access: 'direct',
            type: 'datasource',
          },
          { metrics: true }
        ),
      });
    });

    afterEach(() => {
      mocks.reportInteraction.mockClear();
    });

    it('shows CTA', async () => {
      // insert form should not be present
      expect(screen.queryByRole('button', { name: /add$/i })).not.toBeInTheDocument();

      // "add new" button is the button on the top of the page, not visible when the CTA is rendered
      expect(screen.queryByRole('button', { name: /add new$/i })).not.toBeInTheDocument();

      // there's no table in the page
      expect(screen.queryByRole('table')).not.toBeInTheDocument();

      const CTAButton = screen.getByRole('button', { name: /add correlation/i });
      expect(CTAButton).toBeInTheDocument();

      fireEvent.click(CTAButton);

      // wait for the form to be rendered and query editor to be mounted
      await waitForElementToBeRemoved(() => screen.queryByText(/loading query editor/i));

      // form's submit button
      expect(screen.getByRole('button', { name: /add$/i })).toBeInTheDocument();
    });

    it('correctly adds correlations', async () => {
      const CTAButton = screen.getByRole('button', { name: /add correlation/i });
      expect(CTAButton).toBeInTheDocument();

      // there's no table in the page, as we are adding the first correlation
      expect(screen.queryByRole('table')).not.toBeInTheDocument();

      fireEvent.click(CTAButton);

      fireEvent.change(screen.getByRole('textbox', { name: /label/i }), { target: { value: 'A Label' } });
      fireEvent.change(screen.getByRole('textbox', { name: /description/i }), { target: { value: 'A Description' } });

      // set source datasource picker value
      fireEvent.keyDown(screen.getByLabelText(/^source$/i), { keyCode: 40 });
      fireEvent.click(screen.getByText('loki'));

      // set target datasource picker value
      fireEvent.keyDown(screen.getByLabelText(/^target$/i), { keyCode: 40 });
      fireEvent.click(screen.getByText('prometheus'));

      fireEvent.change(screen.getByRole('textbox', { name: /target field/i }), { target: { value: 'Line' } });

      await waitForElementToBeRemoved(() => screen.queryByText(/loading query editor/i));

      fireEvent.click(screen.getByRole('button', { name: /add$/i }));

      // Waits for the form to be removed, meaning the correlation got successfully saved
      await waitForElementToBeRemoved(() => screen.queryByRole('button', { name: /add$/i }));

      expect(mocks.reportInteraction).toHaveBeenLastCalledWith('grafana_correlations_added');

      // the table showing correlations should have appeared
      expect(screen.getByRole('table')).toBeInTheDocument();
    });
  });

  describe('With correlations', () => {
    afterEach(() => {
      mocks.reportInteraction.mockClear();
    });

    let queryRowsByCellValue: (columnName: Matcher, textValue: Matcher) => HTMLTableRowElement[];
    let getHeaderByName: (columnName: Matcher) => HTMLTableCellElement;
    let queryCellsByColumnName: (columnName: Matcher) => HTMLTableCellElement[];

    beforeEach(async () => {
      const renderResult = await renderWithContext(
        {
          loki: mockDataSource(
            {
              uid: 'loki',
              name: 'loki',
              readOnly: false,
              jsonData: {},
              access: 'direct',
              type: 'datasource',
            },
            {
              logs: true,
            }
          ),
          prometheus: mockDataSource(
            {
              uid: 'prometheus',
              name: 'prometheus',
              readOnly: false,
              jsonData: {},
              access: 'direct',
              type: 'datasource',
            },
            {
              metrics: true,
            }
          ),
          elastic: mockDataSource(
            {
              uid: 'elastic',
              name: 'elastic',
              readOnly: false,
              jsonData: {},
              access: 'direct',
              type: 'datasource',
            },
            {
              metrics: true,
              logs: true,
            }
          ),
        },
        [
          {
            sourceUID: 'loki',
            targetUID: 'loki',
            uid: '1',
            label: 'Some label',
            config: { field: 'line', target: {}, type: 'query' },
          },
          {
            sourceUID: 'prometheus',
            targetUID: 'loki',
            uid: '2',
            label: 'Prometheus to Loki',
            config: { field: 'label', target: {}, type: 'query' },
          },
        ]
      );
      queryRowsByCellValue = renderResult.queryRowsByCellValue;
      queryCellsByColumnName = renderResult.queryCellsByColumnName;
      getHeaderByName = renderResult.getHeaderByName;
    });

    it('shows a table with correlations', async () => {
      expect(screen.getByRole('table')).toBeInTheDocument();
    });

    it('correctly sorts by source', async () => {
      const sourceHeader = getByRole(getHeaderByName('Source'), 'button');
      fireEvent.click(sourceHeader);
      let cells = queryCellsByColumnName('Source');
      cells.forEach((cell, i, allCells) => {
        const prevCell = allCells[i - 1];
        if (prevCell && prevCell.textContent) {
          expect(cell.textContent?.localeCompare(prevCell.textContent)).toBeGreaterThanOrEqual(0);
        }
      });

      fireEvent.click(sourceHeader);
      cells = queryCellsByColumnName('Source');
      cells.forEach((cell, i, allCells) => {
        const prevCell = allCells[i - 1];
        if (prevCell && prevCell.textContent) {
          expect(cell.textContent?.localeCompare(prevCell.textContent)).toBeLessThanOrEqual(0);
        }
      });
    });

    it('correctly adds correlations', async () => {
      const addNewButton = screen.getByRole('button', { name: /add new/i });
      expect(addNewButton).toBeInTheDocument();
      fireEvent.click(addNewButton);

      fireEvent.change(screen.getByRole('textbox', { name: /label/i }), { target: { value: 'A Label' } });
      fireEvent.change(screen.getByRole('textbox', { name: /description/i }), { target: { value: 'A Description' } });

      // set source datasource picker value
      fireEvent.keyDown(screen.getByLabelText(/^source$/i), { keyCode: 40 });
      fireEvent.click(within(screen.getByLabelText('Select options menu')).getByText('prometheus'));

      // set target datasource picker value
      fireEvent.keyDown(screen.getByLabelText(/^target$/i), { keyCode: 40 });
      fireEvent.click(screen.getByText('elastic'));

      fireEvent.change(screen.getByRole('textbox', { name: /target field/i }), { target: { value: 'Line' } });

      await waitForElementToBeRemoved(() => screen.queryByText(/loading query editor/i));

      fireEvent.click(screen.getByRole('button', { name: /add$/i }));

      // the form should get removed after successful submissions
      await waitForElementToBeRemoved(() => screen.queryByRole('button', { name: /add$/i }));

      expect(mocks.reportInteraction).toHaveBeenLastCalledWith('grafana_correlations_added');
    });

    it('correctly closes the form when clicking on the close icon', async () => {
      const addNewButton = screen.getByRole('button', { name: /add new/i });
      expect(addNewButton).toBeInTheDocument();
      fireEvent.click(addNewButton);

      fireEvent.click(screen.getByRole('button', { name: /close$/i }));

      expect(screen.queryByRole('button', { name: /add$/i })).not.toBeInTheDocument();
    });

    it('correctly deletes correlations', async () => {
      // A row with the correlation should exist
      expect(screen.getByRole('cell', { name: /some label/i })).toBeInTheDocument();

      const tableRows = queryRowsByCellValue('Source', 'loki');

      const deleteButton = within(tableRows[0]).getByRole('button', { name: /delete correlation/i });

      expect(deleteButton).toBeInTheDocument();

      fireEvent.click(deleteButton);

      const confirmButton = within(tableRows[0]).getByRole('button', { name: /delete$/i });
      expect(confirmButton).toBeInTheDocument();

      fireEvent.click(confirmButton);

      await waitForElementToBeRemoved(() => screen.queryByRole('cell', { name: /some label$/i }));

      expect(mocks.reportInteraction).toHaveBeenLastCalledWith('grafana_correlations_deleted');
    });

    it('correctly edits correlations', async () => {
      const tableRows = queryRowsByCellValue('Source', 'loki');

      const rowExpanderButton = within(tableRows[0]).getByRole('button', { name: /toggle row expanded/i });
      fireEvent.click(rowExpanderButton);

      expect(mocks.reportInteraction).toHaveBeenLastCalledWith('grafana_correlations_details_expanded');

      await waitForElementToBeRemoved(() => screen.queryByText(/loading query editor/i));

      fireEvent.change(screen.getByRole('textbox', { name: /label/i }), { target: { value: 'edited label' } });
      fireEvent.change(screen.getByRole('textbox', { name: /description/i }), {
        target: { value: 'edited description' },
      });

      expect(screen.queryByRole('cell', { name: /edited label$/i })).not.toBeInTheDocument();

      fireEvent.click(screen.getByRole('button', { name: /save$/i }));

      await waitFor(() => {
        expect(screen.queryByRole('cell', { name: /edited label$/i })).toBeInTheDocument();
      });

      expect(mocks.reportInteraction).toHaveBeenLastCalledWith('grafana_correlations_edited');
    });
  });

  describe('Read only correlations', () => {
    const correlations: Correlation[] = [
      {
        sourceUID: 'loki',
        targetUID: 'loki',
        uid: '1',
        label: 'Some label',
        config: { field: 'line', target: {}, type: 'query' },
      },
    ];

    beforeEach(async () => {
      await renderWithContext(
        {
          loki: mockDataSource({
            uid: 'loki',
            name: 'loki',
            readOnly: true,
            jsonData: {},
            access: 'direct',
            meta: { info: { logos: {} } } as DataSourcePluginMeta,
            type: 'datasource',
          }),
        },
        correlations
      );
    });

    it("doesn't render delete button", async () => {
      // A row with the correlation should exist
      expect(screen.getByRole('cell', { name: /some label/i })).toBeInTheDocument();

      expect(screen.queryByRole('button', { name: /delete correlation/i })).not.toBeInTheDocument();
    });

    it('edit form is read only', async () => {
      // A row with the correlation should exist
      const rowExpanderButton = screen.getByRole('button', { name: /toggle row expanded/i });

      fireEvent.click(rowExpanderButton);

      expect(mocks.reportInteraction).toHaveBeenLastCalledWith('grafana_correlations_details_expanded');

      // wait for the form to be rendered and query editor to be mounted
      await waitForElementToBeRemoved(() => screen.queryByText(/loading query editor/i));

      // form elements should be readonly
      const labelInput = screen.getByRole('textbox', { name: /label/i });
      expect(labelInput).toBeInTheDocument();
      expect(labelInput).toHaveAttribute('readonly');

      const descriptionInput = screen.getByRole('textbox', { name: /description/i });
      expect(descriptionInput).toBeInTheDocument();
      expect(descriptionInput).toHaveAttribute('readonly');

      // we don't expect the save button to be rendered
      expect(screen.queryByRole('button', { name: 'save' })).not.toBeInTheDocument();
    });
  });
});