// Copyright 2019 Red Hat, Inc
//
// 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 * as React from 'react'
import { connect } from 'react-redux'
import PropTypes from 'prop-types'
import {
  EmptyState,
  EmptyStateIcon,
  EmptyStateVariant,
  PageSection,
  PageSectionVariants,
  Title,
} from '@patternfly/react-core'
import { BuildIcon } from '@patternfly/react-icons'

import { fetchBuildset } from '../actions/build'
import { EmptyPage } from '../containers/Errors'
import { Fetching } from '../containers/Fetching'
import BuildList from '../containers/build/BuildList'
import Buildset from '../containers/build/Buildset'

class BuildsetPage extends React.Component {
  static propTypes = {
    match: PropTypes.object.isRequired,
    tenant: PropTypes.object.isRequired,
    buildset: PropTypes.object,
    isFetching: PropTypes.bool.isRequired,
    fetchBuildset: PropTypes.func.isRequired,
  }

  updateData = () => {
    if (!this.props.buildset) {
      this.props.fetchBuildset(
        this.props.tenant,
        this.props.match.params.buildsetId
      )
    }
  }

  componentDidMount() {
    document.title = 'Zuul Buildset'
    if (this.props.tenant.name) {
      this.updateData()
    }
  }

  componentDidUpdate(prevProps) {
    if (this.props.tenant.name !== prevProps.tenant.name) {
      this.updateData()
    }
  }

  render() {
    const { buildset, isFetching, tenant } = this.props

    // Initial page load
    if (buildset === undefined || isFetching) {
      return <Fetching />
    }

    // Fetching finished, but no buildset found
    if (!buildset) {
      // TODO (felix): Provide some generic error (404?) page. Can we somehow
      // identify the error here?
      return (
        <EmptyPage
          title="This buildset does not exist"
          icon={BuildIcon}
          linkTarget={`${tenant.linkPrefix}/buildsets`}
          linkText="Show all buildsets"
        />
      )
    }

    // Return the build list or an empty state if no builds are part of the
    // buildset.
    const buildsContent = buildset.builds ? (
      <BuildList builds={buildset.builds} />
    ) : (
      <>
        {/* Using an hr above the empty state ensures that the space between
            heading (builds) and empty state is filled and the empty state
            doesn't look like it's lost in space. */}
        <hr />
        <EmptyState variant={EmptyStateVariant.small}>
          <EmptyStateIcon icon={BuildIcon} />
          <Title headingLevel="h4" size="lg">
            This buildset does not contain any builds
          </Title>
        </EmptyState>
      </>
    )

    return (
      <>
        <PageSection variant={PageSectionVariants.light}>
          <Buildset buildset={buildset} />
        </PageSection>
        <PageSection variant={PageSectionVariants.light}>
          <Title headingLevel="h3">
            <BuildIcon
              style={{
                marginRight: 'var(--pf-global--spacer--sm)',
                verticalAlign: '-0.1em',
              }}
            />{' '}
            Builds
          </Title>
          {buildsContent}
        </PageSection>
      </>
    )
  }
}

function mapStateToProps(state, ownProps) {
  const buildsetId = ownProps.match.params.buildsetId
  // This will be undefined if the data is not available yet or null if no
  // buildset could be fetched for the given id.
  const buildset = state.build.buildsets[buildsetId]
  return {
    buildset,
    tenant: state.tenant,
    isFetching: state.build.isFetching,
  }
}

const mapDispatchToProps = { fetchBuildset }

export default connect(mapStateToProps, mapDispatchToProps)(BuildsetPage)