"use client"

import { useEffect, useState } from "react"
import { api, Dataset, SambaShare, NfsShare } from "@/lib/api"
import { Header } from "@/components/Header"
import { Button } from "@/components/ui/button"
import { Dialog } from "@/components/ui/dialog"
import { Plus, Trash2, RefreshCw, ChevronRight, ChevronDown } from "lucide-react"
import { Card, CardContent, CardHeader, CardTitle } from "@/components/ui/card"
import { Badge } from "@/components/ui/badge"

export default function DatasetsPage() {
  const [tab, setTab] = useState<"datasets" | "shares">("datasets")
  const [datasets, setDatasets] = useState<Dataset[]>([])
  const [sambaShares, setSambaShares] = useState<SambaShare[]>([])
  const [nfsShares, setNfsShares] = useState<NfsShare[]>([])
  const [loading, setLoading] = useState(true)
  const [expandedDatasets, setExpandedDatasets] = useState<Set<string>>(new Set())
  const [poolTabs, setPoolTabs] = useState<Map<string, string>>(new Map())

  // Dialogs
  const [showCreateDataset, setShowCreateDataset] = useState(false)
  const [showCreateSambaShare, setShowCreateSambaShare] = useState(false)
  const [showCreateNfsShare, setShowCreateNfsShare] = useState(false)
  const [deleteDataset, setDeleteDataset] = useState<string | null>(null)
  const [deleteSambaShare, setDeleteSambaShare] = useState<string | null>(null)
  const [deleteNfsShare, setDeleteNfsShare] = useState<string | null>(null)

  // Form states
  const [newDatasetName, setNewDatasetName] = useState("")
  const [newSambaName, setNewSambaName] = useState("")
  const [newSambaPath, setNewSambaPath] = useState("")
  const [newSambaComment, setNewSambaComment] = useState("")
  const [newNfsPath, setNewNfsPath] = useState("")
  const [newNfsClients, setNewNfsClients] = useState("")
  const [newNfsOptions, setNewNfsOptions] = useState("ro,sync,no_subtree_check")

  useEffect(() => {
    loadData()
  }, [])

  const loadData = async () => {
    setLoading(true)
    try {
      const [ds, samba, nfs] = await Promise.all([
        api.getDatasets(),
        api.getSambaShares(),
        api.getNfsShares(),
      ])
      setDatasets(ds)
      setSambaShares(samba)
      setNfsShares(nfs)
    } catch (err) {
      console.error("Failed to load data:", err)
    } finally {
      setLoading(false)
    }
  }

  const handleCreateDataset = async () => {
    if (!newDatasetName.trim()) return
    try {
      // Create dataset via API
      await api.createDataset(newDatasetName, {})
      setNewDatasetName("")
      setShowCreateDataset(false)
      loadData()
    } catch (err) {
      console.error("Failed to create dataset:", err)
    }
  }

  const handleDeleteDataset = async (name: string) => {
    try {
      await api.deleteDataset(name)
      setDeleteDataset(null)
      loadData()
    } catch (err) {
      console.error("Failed to delete dataset:", err)
    }
  }

  const handleCreateSambaShare = async () => {
    if (!newSambaName.trim() || !newSambaPath.trim()) return
    try {
      await api.createSambaShare({
        name: newSambaName,
        path: newSambaPath,
        comment: newSambaComment || undefined,
      })
      setNewSambaName("")
      setNewSambaPath("")
      setNewSambaComment("")
      setShowCreateSambaShare(false)
      loadData()
    } catch (err) {
      console.error("Failed to create Samba share:", err)
    }
  }

  const handleDeleteSambaShare = async (name: string) => {
    try {
      await api.deleteSambaShare(name)
      setDeleteSambaShare(null)
      loadData()
    } catch (err) {
      console.error("Failed to delete Samba share:", err)
    }
  }

  const handleCreateNfsShare = async () => {
    if (!newNfsPath.trim() || !newNfsClients.trim()) return
    try {
      await api.createNfsShare({
        path: newNfsPath,
        clients: newNfsClients,
        options: newNfsOptions || undefined,
      })
      setNewNfsPath("")
      setNewNfsClients("")
      setNewNfsOptions("ro,sync,no_subtree_check")
      setShowCreateNfsShare(false)
      loadData()
    } catch (err) {
      console.error("Failed to create NFS share:", err)
    }
  }

  const handleDeleteNfsShare = async (path: string) => {
    try {
      await api.deleteNfsShare(path)
      setDeleteNfsShare(null)
      loadData()
    } catch (err) {
      console.error("Failed to delete NFS share:", err)
    }
  }

  const formatBytes = (bytes: number) => {
    if (bytes === 0) return "0 B"
    const k = 1024
    const sizes = ["B", "KB", "MB", "GB", "TB"]
    const i = Math.floor(Math.log(bytes) / Math.log(k))
    return Math.round((bytes / Math.pow(k, i)) * 100) / 100 + " " + sizes[i]
  }

  const getDatasetDepth = (name: string): number => {
    return name.split("/").length - 1
  }

  const getTopLevelDatasets = (): Dataset[] => {
    return datasets.filter((ds) => ds.name.split("/").length === 1)
  }

  const getPoolStats = (poolName: string) => {
    const poolDatasets = datasets.filter((ds) => ds.name === poolName || ds.name.startsWith(poolName + "/"))
    const totalUsed = poolDatasets.reduce((sum, ds) => sum + (ds.used || 0), 0)
    const totalAvail = poolDatasets[0]?.avail || 0
    const totalSize = totalUsed + totalAvail
    const usagePercent = totalSize > 0 ? (totalUsed / totalSize) * 100 : 0

    return { totalUsed, totalAvail, totalSize, usagePercent }
  }

  const getChildDatasets = (parent: string): Dataset[] => {
    const prefix = parent + "/"
    return datasets.filter((ds) => ds.name.startsWith(prefix) && ds.name !== parent)
  }

  const toggleExpand = (name: string) => {
    const newExpanded = new Set(expandedDatasets)
    if (newExpanded.has(name)) {
      newExpanded.delete(name)
    } else {
      newExpanded.add(name)
    }
    setExpandedDatasets(newExpanded)
  }

  const renderDatasetTree = (parent?: string): React.ReactNode[] => {
    const items: React.ReactNode[] = []
    const datasetList = parent ? getChildDatasets(parent) : getTopLevelDatasets()

    datasetList.forEach((ds) => {
      const children = getChildDatasets(ds.name)
      const isExpanded = expandedDatasets.has(ds.name)
      const depth = getDatasetDepth(ds.name)

      items.push(
        <tr key={ds.name} className="border-b border-border hover:bg-muted/50">
          <td className="px-4 py-3 font-mono text-xs" style={{ paddingLeft: `${depth * 24 + 16}px` }}>
            <div className="flex items-center gap-2">
              {children.length > 0 && (
                <button
                  onClick={() => toggleExpand(ds.name)}
                  className="p-0 hover:bg-muted rounded"
                >
                  {isExpanded ? (
                    <ChevronDown className="w-4 h-4" />
                  ) : (
                    <ChevronRight className="w-4 h-4" />
                  )}
                </button>
              )}
              {children.length === 0 && <div className="w-4" />}
              <span>{ds.name.split("/").pop()}</span>
            </div>
          </td>
          <td className="px-4 py-3">{ds.type}</td>
          <td className="px-4 py-3">{formatBytes(ds.used || 0)}</td>
          <td className="px-4 py-3 text-xs">{ds.mountpoint || "—"}</td>
          <td className="px-4 py-3">{ds.compression || "off"}</td>
          <td className="px-4 py-3">
            <button
              onClick={() => setDeleteDataset(ds.name)}
              className="text-destructive hover:underline"
            >
              <Trash2 className="w-4 h-4" />
            </button>
          </td>
        </tr>
      )

      if (isExpanded && children.length > 0) {
        items.push(...renderDatasetTree(ds.name))
      }
    })

    return items
  }

  if (loading) {
    return <div className="p-8">Loading...</div>
  }

  return (
    <div className="min-h-screen bg-background">
      <Header />
      <div className="max-w-7xl mx-auto px-4 sm:px-6 lg:px-8 py-8">
        <div className="flex items-center justify-between mb-6">
          <h1 className="text-3xl font-bold">Datasets & Shares</h1>
          <Button onClick={loadData} variant="outline" size="sm">
            <RefreshCw className="w-4 h-4" />
          </Button>
        </div>

        {/* Tab Navigation */}
        <div className="flex gap-2 mb-6 border-b border-border">
          <button
            onClick={() => setTab("datasets")}
            className={`px-4 py-2 font-medium transition-colors ${
              tab === "datasets"
                ? "text-foreground border-b-2 border-primary"
                : "text-muted-foreground hover:text-foreground"
            }`}
          >
            Datasets
          </button>
          <button
            onClick={() => setTab("shares")}
            className={`px-4 py-2 font-medium transition-colors ${
              tab === "shares"
                ? "text-foreground border-b-2 border-primary"
                : "text-muted-foreground hover:text-foreground"
            }`}
          >
            Shares (Samba & NFS)
          </button>
        </div>

        {/* Datasets Tab */}
        {tab === "datasets" && (
          <div className="space-y-6">
            <div className="mb-4">
              <Button onClick={() => setShowCreateDataset(true)} size="sm">
                <Plus className="w-4 h-4 mr-2" />
                Create Dataset
              </Button>
            </div>

            {getTopLevelDatasets().map((pool) => {
              const stats = getPoolStats(pool.name)
              const currentPoolTab = poolTabs.get(pool.name) || "filesystems"
              const childDatasets = getChildDatasets(pool.name)

              return (
                <Card key={pool.name}>
                  {/* Pool Header */}
                  <CardHeader className="pb-2">
                    <div className="flex items-center justify-between mb-4">
                      <div className="flex items-center gap-3">
                        <CardTitle className="text-xl">{pool.name}</CardTitle>
                        <Badge variant="outline">ONLINE</Badge>
                      </div>
                      <button
                        onClick={() => setDeleteDataset(pool.name)}
                        className="text-destructive hover:underline"
                      >
                        <Trash2 className="w-4 h-4" />
                      </button>
                    </div>

                    {/* Pool Stats Grid */}
                    <div className="grid grid-cols-2 md:grid-cols-5 gap-4 mb-4">
                      <div>
                        <p className="text-xs text-muted-foreground">Size</p>
                        <p className="font-bold">{formatBytes(stats.totalSize)}</p>
                      </div>
                      <div>
                        <p className="text-xs text-muted-foreground">Allocated</p>
                        <p className="font-bold">{formatBytes(stats.totalUsed)}</p>
                      </div>
                      <div>
                        <p className="text-xs text-muted-foreground">Free</p>
                        <p className="font-bold">{formatBytes(stats.totalAvail)}</p>
                      </div>
                      <div>
                        <p className="text-xs text-muted-foreground">Fragmentation</p>
                        <p className="font-bold">0%</p>
                      </div>
                      <div>
                        <p className="text-xs text-muted-foreground">Usage</p>
                        <p className="font-bold">{stats.usagePercent.toFixed(1)}%</p>
                      </div>
                    </div>

                    {/* Usage Bar */}
                    <div className="space-y-1">
                      <div className="flex h-6 bg-muted rounded overflow-hidden">
                        <div
                          className="bg-blue-500"
                          style={{ width: `${stats.usagePercent}%` }}
                        />
                        <div
                          className="bg-green-500"
                          style={{ width: `${100 - stats.usagePercent}%` }}
                        />
                      </div>
                      <p className="text-xs text-muted-foreground text-center">
                        {stats.usagePercent.toFixed(2)}% Allocated • {(100 - stats.usagePercent).toFixed(2)}% Free
                      </p>
                    </div>
                  </CardHeader>

                  {/* Tabs */}
                  <CardContent>
                    <div className="border-b border-border mb-4">
                      <div className="flex gap-4">
                        <button
                          onClick={() => setPoolTabs(new Map(poolTabs).set(pool.name, "filesystems"))}
                          className={`px-4 py-2 font-medium transition-colors ${
                            currentPoolTab === "filesystems"
                              ? "border-b-2 border-primary text-primary"
                              : "text-muted-foreground hover:text-foreground"
                          }`}
                        >
                          File Systems ({childDatasets.length + 1})
                        </button>
                        <button
                          onClick={() => setPoolTabs(new Map(poolTabs).set(pool.name, "snapshots"))}
                          className={`px-4 py-2 font-medium transition-colors ${
                            currentPoolTab === "snapshots"
                              ? "border-b-2 border-primary text-primary"
                              : "text-muted-foreground hover:text-foreground"
                          }`}
                        >
                          Snapshots
                        </button>
                        <button
                          onClick={() => setPoolTabs(new Map(poolTabs).set(pool.name, "status"))}
                          className={`px-4 py-2 font-medium transition-colors ${
                            currentPoolTab === "status"
                              ? "border-b-2 border-primary text-primary"
                              : "text-muted-foreground hover:text-foreground"
                          }`}
                        >
                          Status
                        </button>
                      </div>
                    </div>

                    {/* File Systems Tab */}
                    {currentPoolTab === "filesystems" && (
                      <div className="overflow-x-auto">
                        <table className="w-full text-sm">
                          <thead className="bg-muted">
                            <tr>
                              <th className="px-4 py-2 text-left font-medium text-xs">Name</th>
                              <th className="px-4 py-2 text-left font-medium text-xs">Type</th>
                              <th className="px-4 py-2 text-left font-medium text-xs">Used</th>
                              <th className="px-4 py-2 text-left font-medium text-xs">Available</th>
                              <th className="px-4 py-2 text-left font-medium text-xs">Mountpoint</th>
                              <th className="px-4 py-2 text-left font-medium text-xs">Compression</th>
                            </tr>
                          </thead>
                          <tbody>
                            <tr className="border-b border-border/50 hover:bg-muted/30">
                              <td className="px-4 py-2 font-mono text-xs">{pool.name}</td>
                              <td className="px-4 py-2 text-xs">{pool.type}</td>
                              <td className="px-4 py-2 text-xs">{formatBytes(pool.used || 0)}</td>
                              <td className="px-4 py-2 text-xs">{formatBytes(pool.avail || 0)}</td>
                              <td className="px-4 py-2 text-xs">{pool.mountpoint || "—"}</td>
                              <td className="px-4 py-2 text-xs">{pool.compression || "off"}</td>
                            </tr>
                            {childDatasets.map((ds) => (
                              <tr key={ds.name} className="border-b border-border/50 hover:bg-muted/30">
                                <td className="px-4 py-2 font-mono text-xs" style={{ paddingLeft: "32px" }}>
                                  {ds.name.split("/").pop()}
                                </td>
                                <td className="px-4 py-2 text-xs">{ds.type}</td>
                                <td className="px-4 py-2 text-xs">{formatBytes(ds.used || 0)}</td>
                                <td className="px-4 py-2 text-xs">{formatBytes(ds.avail || 0)}</td>
                                <td className="px-4 py-2 text-xs">{ds.mountpoint || "—"}</td>
                                <td className="px-4 py-2 text-xs">{ds.compression || "off"}</td>
                              </tr>
                            ))}
                          </tbody>
                        </table>
                      </div>
                    )}

                    {/* Snapshots Tab */}
                    {currentPoolTab === "snapshots" && (
                      <div className="text-center py-8 text-muted-foreground text-sm">
                        See Snapshots page for detailed snapshot management
                      </div>
                    )}

                    {/* Status Tab */}
                    {currentPoolTab === "status" && (
                      <div className="grid grid-cols-2 md:grid-cols-3 gap-4">
                        <div>
                          <p className="text-xs text-muted-foreground">Health</p>
                          <p className="font-bold">ONLINE</p>
                        </div>
                        <div>
                          <p className="text-xs text-muted-foreground">Mounted</p>
                          <p className="font-bold">Yes</p>
                        </div>
                        <div>
                          <p className="text-xs text-muted-foreground">Record Size</p>
                          <p className="font-bold">128 KiB</p>
                        </div>
                      </div>
                    )}
                  </CardContent>
                </Card>
              )
            })}

            {datasets.length === 0 && (
              <div className="text-center py-8 text-muted-foreground">No datasets found</div>
            )}
          </div>
        )}

        {/* Shares Tab */}
        {tab === "shares" && (
          <div>
            <div className="mb-8">
              <h2 className="text-xl font-bold mb-4">Samba Shares</h2>
              <div className="mb-4">
                <Button onClick={() => setShowCreateSambaShare(true)} size="sm">
                  <Plus className="w-4 h-4 mr-2" />
                  Create Samba Share
                </Button>
              </div>

              <div className="border border-border rounded-lg overflow-x-auto">
                <table className="w-full text-sm">
                  <thead className="bg-muted border-b border-border">
                    <tr>
                      <th className="px-4 py-3 text-left font-medium">Name</th>
                      <th className="px-4 py-3 text-left font-medium">Path</th>
                      <th className="px-4 py-3 text-left font-medium">Comment</th>
                      <th className="px-4 py-3 text-left font-medium">Action</th>
                    </tr>
                  </thead>
                  <tbody>
                    {sambaShares.map((share) => (
                      <tr key={share.name} className="border-b border-border hover:bg-muted/50">
                        <td className="px-4 py-3 font-mono text-xs">{share.name}</td>
                        <td className="px-4 py-3 text-xs">{share.path}</td>
                        <td className="px-4 py-3 text-xs">{share.comment || "—"}</td>
                        <td className="px-4 py-3">
                          <button
                            onClick={() => setDeleteSambaShare(share.name)}
                            className="text-destructive hover:underline"
                          >
                            <Trash2 className="w-4 h-4" />
                          </button>
                        </td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>

              {sambaShares.length === 0 && (
                <div className="text-center py-4 text-muted-foreground text-sm">
                  No Samba shares
                </div>
              )}
            </div>

            <div>
              <h2 className="text-xl font-bold mb-4">NFS Shares</h2>
              <div className="mb-4">
                <Button onClick={() => setShowCreateNfsShare(true)} size="sm">
                  <Plus className="w-4 h-4 mr-2" />
                  Create NFS Share
                </Button>
              </div>

              <div className="border border-border rounded-lg overflow-x-auto">
                <table className="w-full text-sm">
                  <thead className="bg-muted border-b border-border">
                    <tr>
                      <th className="px-4 py-3 text-left font-medium">Path</th>
                      <th className="px-4 py-3 text-left font-medium">Clients</th>
                      <th className="px-4 py-3 text-left font-medium">Options</th>
                      <th className="px-4 py-3 text-left font-medium">Action</th>
                    </tr>
                  </thead>
                  <tbody>
                    {nfsShares.map((share) => (
                      <tr key={share.path} className="border-b border-border hover:bg-muted/50">
                        <td className="px-4 py-3 text-xs font-mono">{share.path}</td>
                        <td className="px-4 py-3 text-xs">{share.clients}</td>
                        <td className="px-4 py-3 text-xs">{share.options || "—"}</td>
                        <td className="px-4 py-3">
                          <button
                            onClick={() => setDeleteNfsShare(share.path)}
                            className="text-destructive hover:underline"
                          >
                            <Trash2 className="w-4 h-4" />
                          </button>
                        </td>
                      </tr>
                    ))}
                  </tbody>
                </table>
              </div>

              {nfsShares.length === 0 && (
                <div className="text-center py-4 text-muted-foreground text-sm">
                  No NFS shares
                </div>
              )}
            </div>
          </div>
        )}
      </div>

      {/* Create Dataset Dialog */}
      <Dialog
        open={showCreateDataset}
        onClose={() => setShowCreateDataset(false)}
        title="Create Dataset"
      >
        <input
          type="text"
          placeholder="dataset name (e.g., tank/data)"
          value={newDatasetName}
          onChange={(e) => setNewDatasetName(e.target.value)}
          className="w-full border border-input rounded px-3 py-2 mb-4 bg-background text-foreground"
        />
        <div className="flex gap-2">
          <Button onClick={handleCreateDataset} className="flex-1">
            Create
          </Button>
          <Button
            onClick={() => setShowCreateDataset(false)}
            variant="outline"
            className="flex-1"
          >
            Cancel
          </Button>
        </div>
      </Dialog>

      {/* Delete Dataset Dialog */}
      <Dialog
        open={!!deleteDataset}
        onClose={() => setDeleteDataset(null)}
        title="Delete Dataset"
      >
        <p className="mb-4 text-sm">
          Are you sure you want to delete <span className="font-mono">{deleteDataset}</span>?
          This cannot be undone.
        </p>
        <div className="flex gap-2">
          <Button
            onClick={() => deleteDataset && handleDeleteDataset(deleteDataset)}
            variant="destructive"
            className="flex-1"
          >
            Delete
          </Button>
          <Button
            onClick={() => setDeleteDataset(null)}
            variant="outline"
            className="flex-1"
          >
            Cancel
          </Button>
        </div>
      </Dialog>

      {/* Create Samba Share Dialog */}
      <Dialog
        open={showCreateSambaShare}
        onClose={() => setShowCreateSambaShare(false)}
        title="Create Samba Share"
      >
        <input
          type="text"
          placeholder="share name"
          value={newSambaName}
          onChange={(e) => setNewSambaName(e.target.value)}
          className="w-full border border-input rounded px-3 py-2 mb-3 bg-background text-foreground text-sm"
        />
        <input
          type="text"
          placeholder="path (e.g., /mnt/tank/share)"
          value={newSambaPath}
          onChange={(e) => setNewSambaPath(e.target.value)}
          className="w-full border border-input rounded px-3 py-2 mb-3 bg-background text-foreground text-sm"
        />
        <input
          type="text"
          placeholder="comment (optional)"
          value={newSambaComment}
          onChange={(e) => setNewSambaComment(e.target.value)}
          className="w-full border border-input rounded px-3 py-2 mb-4 bg-background text-foreground text-sm"
        />
        <div className="flex gap-2">
          <Button onClick={handleCreateSambaShare} className="flex-1">
            Create
          </Button>
          <Button
            onClick={() => setShowCreateSambaShare(false)}
            variant="outline"
            className="flex-1"
          >
            Cancel
          </Button>
        </div>
      </Dialog>

      {/* Delete Samba Share Dialog */}
      <Dialog
        open={!!deleteSambaShare}
        onClose={() => setDeleteSambaShare(null)}
        title="Delete Samba Share"
      >
        <p className="mb-4 text-sm">
          Are you sure you want to delete <span className="font-mono">{deleteSambaShare}</span>?
        </p>
        <div className="flex gap-2">
          <Button
            onClick={() => deleteSambaShare && handleDeleteSambaShare(deleteSambaShare)}
            variant="destructive"
            className="flex-1"
          >
            Delete
          </Button>
          <Button
            onClick={() => setDeleteSambaShare(null)}
            variant="outline"
            className="flex-1"
          >
            Cancel
          </Button>
        </div>
      </Dialog>

      {/* Create NFS Share Dialog */}
      <Dialog
        open={showCreateNfsShare}
        onClose={() => setShowCreateNfsShare(false)}
        title="Create NFS Share"
      >
        <input
          type="text"
          placeholder="path (e.g., /mnt/tank/share)"
          value={newNfsPath}
          onChange={(e) => setNewNfsPath(e.target.value)}
          className="w-full border border-input rounded px-3 py-2 mb-3 bg-background text-foreground text-sm"
        />
        <input
          type="text"
          placeholder="clients (e.g., 192.168.1.0/24 or *)"
          value={newNfsClients}
          onChange={(e) => setNewNfsClients(e.target.value)}
          className="w-full border border-input rounded px-3 py-2 mb-3 bg-background text-foreground text-sm"
        />
        <input
          type="text"
          placeholder="options"
          value={newNfsOptions}
          onChange={(e) => setNewNfsOptions(e.target.value)}
          className="w-full border border-input rounded px-3 py-2 mb-4 bg-background text-foreground text-sm"
        />
        <div className="flex gap-2">
          <Button onClick={handleCreateNfsShare} className="flex-1">
            Create
          </Button>
          <Button
            onClick={() => setShowCreateNfsShare(false)}
            variant="outline"
            className="flex-1"
          >
            Cancel
          </Button>
        </div>
      </Dialog>

      {/* Delete NFS Share Dialog */}
      <Dialog
        open={!!deleteNfsShare}
        onClose={() => setDeleteNfsShare(null)}
        title="Delete NFS Share"
      >
        <p className="mb-4 text-sm">
          Are you sure you want to delete <span className="font-mono">{deleteNfsShare}</span>?
        </p>
        <div className="flex gap-2">
          <Button
            onClick={() => deleteNfsShare && handleDeleteNfsShare(deleteNfsShare)}
            variant="destructive"
            className="flex-1"
          >
            Delete
          </Button>
          <Button
            onClick={() => setDeleteNfsShare(null)}
            variant="outline"
            className="flex-1"
          >
            Cancel
          </Button>
        </div>
      </Dialog>
    </div>
  )
}