'use client'

import { useState, useEffect, useCallback } from 'react'
import type { TabId, Tenant, Namespace, Role, UserRole, LLMPolicy } from './types'
import { SDK_BASE_URL } from './types'

export interface RbacStats {
  tenants: number
  namespaces: number
  roles: number
  systemRoles: number
  policies: number
  activeUsers: number
}

export function useRbacData() {
  const [activeTab, setActiveTab] = useState<TabId>('tenants')
  const [loading, setLoading] = useState(true)
  const [error, setError] = useState<string | null>(null)

  // Data states
  const [tenants, setTenants] = useState<Tenant[]>([])
  const [namespaces, setNamespaces] = useState<Namespace[]>([])
  const [roles, setRoles] = useState<Role[]>([])
  const [userRoles, setUserRoles] = useState<UserRole[]>([])
  const [policies, setPolicies] = useState<LLMPolicy[]>([])

  // Filter states
  const [selectedTenantId, setSelectedTenantId] = useState<string>('')
  const [searchTerm, setSearchTerm] = useState('')

  // Modal states
  const [showCreateModal, setShowCreateModal] = useState(false)
  const [editItem, setEditItem] = useState<any>(null)

  // Load data based on active tab
  const loadData = useCallback(async () => {
    setLoading(true)
    setError(null)

    try {
      const headers: Record<string, string> = {
        'Content-Type': 'application/json',
      }

      if (selectedTenantId) {
        headers['X-Tenant-ID'] = selectedTenantId
      }

      switch (activeTab) {
        case 'tenants': {
          const res = await fetch(`${SDK_BASE_URL}/sdk/v1/tenants`, { headers })
          if (res.ok) {
            const data = await res.json()
            setTenants(data.tenants || [])
          }
          break
        }
        case 'namespaces': {
          if (!selectedTenantId) {
            setNamespaces([])
            break
          }
          const res = await fetch(`${SDK_BASE_URL}/sdk/v1/tenants/${selectedTenantId}/namespaces`, { headers })
          if (res.ok) {
            const data = await res.json()
            setNamespaces(data.namespaces || [])
          }
          break
        }
        case 'roles': {
          const res = await fetch(`${SDK_BASE_URL}/sdk/v1/roles`, { headers })
          if (res.ok) {
            const data = await res.json()
            setRoles(data.roles || [])
          }
          break
        }
        case 'users': {
          // This would need a user ID - for now show empty
          setUserRoles([])
          break
        }
        case 'policies': {
          const res = await fetch(`${SDK_BASE_URL}/sdk/v1/llm/policies`, { headers })
          if (res.ok) {
            const data = await res.json()
            setPolicies(data.policies || [])
          }
          break
        }
      }
    } catch (err) {
      console.error('Failed to load data:', err)
      setError('Verbindung zum AI Compliance SDK fehlgeschlagen. Stellen Sie sicher, dass der SDK-Service laeuft.')
    } finally {
      setLoading(false)
    }
  }, [activeTab, selectedTenantId])

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

  // Load tenants on mount for the filter
  useEffect(() => {
    const loadTenants = async () => {
      try {
        const res = await fetch(`${SDK_BASE_URL}/sdk/v1/tenants`)
        if (res.ok) {
          const data = await res.json()
          setTenants(data.tenants || [])
          if (data.tenants?.length > 0 && !selectedTenantId) {
            setSelectedTenantId(data.tenants[0].id)
          }
        }
      } catch (err) {
        console.error('Failed to load tenants:', err)
      }
    }
    loadTenants()
  }, [])

  const handleCreate = async (data: any) => {
    try {
      const headers: Record<string, string> = {
        'Content-Type': 'application/json',
      }

      if (selectedTenantId) {
        headers['X-Tenant-ID'] = selectedTenantId
      }

      let endpoint = ''
      switch (activeTab) {
        case 'tenants':
          endpoint = `${SDK_BASE_URL}/sdk/v1/tenants`
          break
        case 'namespaces':
          endpoint = `${SDK_BASE_URL}/sdk/v1/tenants/${selectedTenantId}/namespaces`
          break
        case 'roles':
          endpoint = `${SDK_BASE_URL}/sdk/v1/roles`
          break
        case 'policies':
          endpoint = `${SDK_BASE_URL}/sdk/v1/llm/policies`
          break
      }

      const res = await fetch(endpoint, {
        method: 'POST',
        headers,
        body: JSON.stringify(data),
      })

      if (res.ok) {
        setShowCreateModal(false)
        loadData()
      } else {
        const errData = await res.json()
        alert(`Fehler: ${errData.error || 'Unbekannter Fehler'}`)
      }
    } catch (err) {
      console.error('Create failed:', err)
      alert('Erstellen fehlgeschlagen')
    }
  }

  const filteredData = () => {
    const term = searchTerm.toLowerCase()

    switch (activeTab) {
      case 'tenants':
        return tenants.filter(t =>
          t.name.toLowerCase().includes(term) ||
          t.slug.toLowerCase().includes(term)
        )
      case 'namespaces':
        return namespaces.filter(n =>
          n.name.toLowerCase().includes(term) ||
          n.slug.toLowerCase().includes(term)
        )
      case 'roles':
        return roles.filter(r =>
          r.name.toLowerCase().includes(term) ||
          r.description?.toLowerCase().includes(term)
        )
      case 'policies':
        return policies.filter(p =>
          p.name.toLowerCase().includes(term)
        )
      default:
        return []
    }
  }

  const stats: RbacStats = {
    tenants: tenants.length,
    namespaces: namespaces.length,
    roles: roles.length,
    systemRoles: roles.filter(r => r.is_system_role).length,
    policies: policies.length,
    activeUsers: userRoles.length,
  }

  return {
    activeTab,
    setActiveTab,
    loading,
    error,
    tenants,
    userRoles,
    selectedTenantId,
    setSelectedTenantId,
    searchTerm,
    setSearchTerm,
    showCreateModal,
    setShowCreateModal,
    editItem,
    setEditItem,
    handleCreate,
    filteredData,
    stats,
  }
}