import { PermissionAction } from '@supabase/shared-types/out/constants'
import { partition } from 'lodash'
import { ChevronDown, Globe2, Loader2, Network } from 'lucide-react'
import { useTheme } from 'next-themes'
import Link from 'next/link'
import { useEffect, useMemo, useState } from 'react'
import ReactFlow, { Background, Edge, ReactFlowProvider, useReactFlow } from 'reactflow'

import 'reactflow/dist/style.css'

import { useParams } from 'common'
import AlertError from 'components/ui/AlertError'
import { ButtonTooltip } from 'components/ui/ButtonTooltip'
import { useLoadBalancersQuery } from 'data/read-replicas/load-balancers-query'
import { Database, useReadReplicasQuery } from 'data/read-replicas/replicas-query'
import {
  ReplicaInitializationStatus,
  useReadReplicasStatusesQuery,
} from 'data/read-replicas/replicas-status-query'
import { useAsyncCheckPermissions } from 'hooks/misc/useCheckPermissions'
import { useIsFeatureEnabled } from 'hooks/misc/useIsFeatureEnabled'
import {
  useIsAwsCloudProvider,
  useIsOrioleDb,
  useSelectedProjectQuery,
} from 'hooks/misc/useSelectedProject'
import { timeout } from 'lib/helpers'
import { useRouter } from 'next/router'
import {
  Button,
  cn,
  DropdownMenu,
  DropdownMenuContent,
  DropdownMenuItem,
  DropdownMenuSeparator,
  DropdownMenuTrigger,
} from 'ui'

import DropAllReplicasConfirmationModal from './DropAllReplicasConfirmationModal'
import { DropReplicaConfirmationModal } from './DropReplicaConfirmationModal'
import { SmoothstepEdge } from './Edge'
import { REPLICA_STATUS } from './InstanceConfiguration.constants'
import { addRegionNodes, generateNodes, getDagreGraphLayout } from './InstanceConfiguration.utils'
import { LoadBalancerNode, PrimaryNode, RegionNode, ReplicaNode } from './InstanceNode'
import MapView from './MapView'
import { RestartReplicaConfirmationModal } from './RestartReplicaConfirmationModal'

interface InstanceConfigurationUIProps {
  diagramOnly?: boolean
}

const InstanceConfigurationUI = ({ diagramOnly = false }: InstanceConfigurationUIProps) => {
  const router = useRouter()
  const reactFlow = useReactFlow()
  const isOrioleDb = useIsOrioleDb()
  const { resolvedTheme } = useTheme()
  const { ref: projectRef } = useParams()
  const { isPending: isLoadingProject } = useSelectedProjectQuery()

  const isAws = useIsAwsCloudProvider()
  const { infrastructureReadReplicas } = useIsFeatureEnabled(['infrastructure:read_replicas'])
  const newReplicaURL = `/project/${projectRef}/database/replication?type=Read+Replica`

  const [view, setView] = useState<'flow' | 'map'>('flow')
  const [showDeleteAllModal, setShowDeleteAllModal] = useState(false)
  const [refetchInterval, setRefetchInterval] = useState<number | false>(10000)
  const [selectedReplicaToDrop, setSelectedReplicaToDrop] = useState<Database>()
  const [selectedReplicaToRestart, setSelectedReplicaToRestart] = useState<Database>()

  const { can: canManageReplicas } = useAsyncCheckPermissions(PermissionAction.CREATE, 'projects')

  const {
    data: loadBalancers,
    refetch: refetchLoadBalancers,
    isSuccess: isSuccessLoadBalancers,
  } = useLoadBalancersQuery({ projectRef })
  const {
    data,
    error,
    refetch: refetchReplicas,
    isPending: isLoading,
    isError,
    isSuccess: isSuccessReplicas,
  } = useReadReplicasQuery({ projectRef })
  const [[primary], replicas] = useMemo(
    () => partition(data ?? [], (db) => db.identifier === projectRef),
    [data, projectRef]
  )
  const numReplicas = useMemo(() => data?.length ?? 0, [data])

  const { data: replicasStatuses, isSuccess: isSuccessReplicasStatuses } =
    useReadReplicasStatusesQuery(
      { projectRef },
      {
        refetchInterval: refetchInterval,
        refetchOnWindowFocus: false,
      }
    )

  useEffect(() => {
    if (!isSuccessReplicasStatuses) return
    const refetch = async () => {
      const fixedStatues = [
        REPLICA_STATUS.ACTIVE_HEALTHY,
        REPLICA_STATUS.ACTIVE_UNHEALTHY,
        REPLICA_STATUS.INIT_READ_REPLICA_FAILED,
      ]
      const replicasInTransition = replicasStatuses.filter((db) => {
        const { status } = db.replicaInitializationStatus || {}
        return (
          !fixedStatues.includes(db.status) || status === ReplicaInitializationStatus.InProgress
        )
      })
      const hasTransientStatus = replicasInTransition.length > 0

      // If any replica's status has changed, refetch databases
      if (replicasStatuses.length !== numReplicas) {
        await refetchReplicas()
        setTimeout(() => refetchLoadBalancers(), 2000)
      }

      // If all replicas are active healthy, stop fetching statuses
      if (!hasTransientStatus) {
        setRefetchInterval(false)
      }
    }
    refetch()
  }, [
    numReplicas,
    isSuccessReplicasStatuses,
    refetchLoadBalancers,
    refetchReplicas,
    replicasStatuses,
  ])

  const backgroundPatternColor =
    resolvedTheme === 'dark' ? 'rgba(255, 255, 255, 0.3)' : 'rgba(0, 0, 0, 0.4)'

  const nodes = useMemo(
    () =>
      isSuccessReplicas && isSuccessLoadBalancers && primary !== undefined
        ? generateNodes({
            primary,
            replicas,
            loadBalancers: loadBalancers ?? [],
            onSelectRestartReplica: setSelectedReplicaToRestart,
            onSelectDropReplica: setSelectedReplicaToDrop,
          })
        : [],
    [isSuccessReplicas, isSuccessLoadBalancers, primary, replicas, loadBalancers]
  )

  const edges: Edge[] = useMemo(
    () =>
      isSuccessReplicas && isSuccessLoadBalancers
        ? [
            ...((loadBalancers ?? []).length > 0
              ? [
                  {
                    id: `load-balancer-${primary.identifier}`,
                    source: 'load-balancer',
                    target: primary.identifier,
                    type: 'smoothstep',
                    animated: true,
                    className: '!cursor-default',
                  },
                ]
              : []),
            ...replicas.map((database) => {
              return {
                id: `${primary.identifier}-${database.identifier}`,
                source: primary.identifier,
                target: database.identifier,
                type: 'smoothstep',
                animated: true,
                className: '!cursor-default',
                data: {
                  status: database.status,
                  identifier: database.identifier,
                  connectionString: database.connectionString,
                },
              }
            }),
          ]
        : [],
    [isSuccessLoadBalancers, isSuccessReplicas, loadBalancers, primary?.identifier, replicas]
  )

  const nodeTypes = useMemo(
    () => ({
      PRIMARY: PrimaryNode,
      READ_REPLICA: ReplicaNode,
      REGION: RegionNode,
      LOAD_BALANCER: LoadBalancerNode,
    }),
    []
  )

  const edgeTypes = useMemo(
    () => ({
      smoothstep: SmoothstepEdge,
    }),
    []
  )

  const setReactFlow = async () => {
    const graph = getDagreGraphLayout(nodes, edges)
    const { nodes: updatedNodes } = addRegionNodes(graph.nodes, graph.edges)
    reactFlow.setNodes(updatedNodes)
    reactFlow.setEdges(graph.edges)

    // [Joshen] Odd fix to ensure that react flow snaps back to center when adding nodes
    await timeout(1)
    reactFlow.fitView({ maxZoom: 0.9, minZoom: 0.9 })
  }

  // [Joshen] Just FYI this block is oddly triggering whenever we refocus on the viewport
  // even if I change the dependency array to just data. Not blocker, just an area to optimize
  useEffect(() => {
    if (isSuccessReplicas && isSuccessLoadBalancers && nodes.length > 0 && view === 'flow') {
      setReactFlow()
    }
  }, [isSuccessReplicas, isSuccessLoadBalancers, nodes, edges, view])

  return (
    <div className={cn('nowheel', diagramOnly ? 'h-full' : 'border-y')}>
      <div
        className={`${diagramOnly ? 'h-full' : 'h-[500px]'} w-full relative ${
          isSuccessReplicas && !isLoadingProject ? '' : 'flex items-center justify-center px-28'
        }`}
      >
        {/* Sometimes the read replicas are loaded before the project info and causes  read replicas to be shown on Fly deploys.
            You can replicate this to going to this page and refresh. This isLoadingProject flag fixes that. */}
        {(isLoading || isLoadingProject) && (
          <Loader2 className="animate-spin text-foreground-light" />
        )}
        {isError && <AlertError error={error} subject="Failed to retrieve replicas" />}
        {isSuccessReplicas && !isLoadingProject && (
          <>
            {!diagramOnly && infrastructureReadReplicas && (
              <div className="z-10 absolute top-4 right-4 flex items-center justify-center gap-x-2">
                <div className="flex items-center justify-center">
                  <ButtonTooltip
                    asChild
                    type="default"
                    disabled={!canManageReplicas || isOrioleDb}
                    className={cn(replicas.length > 0 ? 'rounded-r-none' : '')}
                    tooltip={{
                      content: {
                        side: 'bottom',
                        text: !canManageReplicas
                          ? 'You need additional permissions to deploy replicas'
                          : isOrioleDb
                            ? 'Read replicas are not supported with OrioleDB'
                            : undefined,
                      },
                    }}
                  >
                    <Link href={newReplicaURL}>Deploy a new replica</Link>
                  </ButtonTooltip>
                  {replicas.length > 0 && (
                    <DropdownMenu>
                      <DropdownMenuTrigger asChild>
                        <Button
                          type="default"
                          icon={<ChevronDown size={16} />}
                          className="px-1 rounded-l-none border-l-0"
                        />
                      </DropdownMenuTrigger>
                      <DropdownMenuContent align="end" className="w-52 *:space-x-2">
                        <DropdownMenuItem asChild>
                          <Link href={`/project/${projectRef}/settings/compute-and-disk`}>
                            Resize databases
                          </Link>
                        </DropdownMenuItem>
                        <DropdownMenuSeparator />
                        <DropdownMenuItem onClick={() => setShowDeleteAllModal(true)}>
                          <div>Remove all replicas</div>
                        </DropdownMenuItem>
                      </DropdownMenuContent>
                    </DropdownMenu>
                  )}
                </div>
                {isAws && (
                  <div className="flex items-center justify-center">
                    <Button
                      type="default"
                      icon={<Network size={15} />}
                      className={`rounded-r-none transition ${
                        view === 'flow' ? 'opacity-100' : 'opacity-50'
                      }`}
                      onClick={() => setView('flow')}
                    />
                    <Button
                      type="default"
                      icon={<Globe2 size={15} />}
                      className={`rounded-l-none transition ${
                        view === 'map' ? 'opacity-100' : 'opacity-50'
                      }`}
                      onClick={() => setView('map')}
                    />
                  </div>
                )}
              </div>
            )}
            {view === 'flow' ? (
              <ReactFlow
                fitView
                fitViewOptions={{ minZoom: 0.9, maxZoom: 0.9 }}
                className="instance-configuration"
                zoomOnPinch={false}
                zoomOnScroll={false}
                nodesDraggable={false}
                nodesConnectable={false}
                zoomOnDoubleClick={false}
                edgesFocusable={false}
                edgesUpdatable={false}
                defaultNodes={[]}
                defaultEdges={[]}
                nodeTypes={nodeTypes}
                edgeTypes={edgeTypes}
                proOptions={{ hideAttribution: true }}
              >
                <Background color={backgroundPatternColor} />
              </ReactFlow>
            ) : (
              <MapView
                onSelectDeployNewReplica={() => router.push(newReplicaURL)}
                onSelectRestartReplica={setSelectedReplicaToRestart}
                onSelectDropReplica={setSelectedReplicaToDrop}
              />
            )}
          </>
        )}
      </div>

      {!diagramOnly && (
        <>
          <DropReplicaConfirmationModal
            selectedReplica={selectedReplicaToDrop}
            onSuccess={() => setRefetchInterval(5000)}
            onCancel={() => setSelectedReplicaToDrop(undefined)}
          />

          <DropAllReplicasConfirmationModal
            visible={showDeleteAllModal}
            onSuccess={() => setRefetchInterval(5000)}
            onCancel={() => setShowDeleteAllModal(false)}
          />

          <RestartReplicaConfirmationModal
            selectedReplica={selectedReplicaToRestart}
            onSuccess={() => setRefetchInterval(5000)}
            onCancel={() => setSelectedReplicaToRestart(undefined)}
          />
        </>
      )}
    </div>
  )
}

interface InstanceConfigurationProps {
  diagramOnly?: boolean
}

export const InstanceConfiguration = ({ diagramOnly = false }: InstanceConfigurationProps) => {
  return (
    <ReactFlowProvider>
      <InstanceConfigurationUI diagramOnly={diagramOnly} />
    </ReactFlowProvider>
  )
}