import { useState, useEffect, useCallback } from 'react'
import { SystemInfo } from '../config'

const defaultSystemInfo: SystemInfo = {
  wordpress: {
    version: '',
    multisite: false,
    memoryLimit: '',
    debugMode: false,
    cron: true,
    language: '',
    timezone: '',
    permalinkStructure: '',
  },
  php: {
    version: '',
    memoryLimit: '',
    maxExecutionTime: '',
    maxInputVars: '',
    postMaxSize: '',
    uploadMaxFilesize: '',
    safeMode: false,
    openBasedir: false,
    extensions: [],
    disabledFunctions: [],
  },
  mysql: {
    version: '',
    maxConnections: '',
    maxPacketSize: '',
    storageEngine: '',
  },
  server: {
    software: '',
    serverProtocol: '',
    documentRoot: '',
    serverAddress: '',
  },
  woocommerce: {
    version: '',
    databaseVersion: '',
    currency: '',
    currencyPosition: '',
    thousandSeparator: '',
    decimalSeparator: '',
    productsCount: 0,
    ordersCount: 0,
  },
  swiftCommerce: {
    version: '',
    proVersion: '',
    featuresEnabled: [],
  },
  registrationForms: {
    wordpress: {
      usersCanRegister: false,
      emailVerificationEnabled: false,
      registrationFormEnabled: false,
      activeOwner: 'None',
      registerFormHookCallbacks: 0,
      registrationErrorsHookCallbacks: 0,
    },
    woocommerce: {
      available: false,
      myAccountRegistrationEnabled: false,
      generateUsername: '',
      generatePassword: '',
      myAccountPageId: 0,
      myAccountPageUsesShortcode: false,
      myAccountPageUsesBlock: false,
      themeTemplateOverride: '',
      emailVerificationEnabled: false,
      registrationFormEnabled: false,
      activeOwner: 'None',
      woocommerceRegisterFormHookCallbacks: 0,
      woocommerceRegistrationErrorsHookCallbacks: 0,
    },
    conflict: {
      registrationFormMode: 'registration_form',
      wordpressConflict: false,
      woocommerceConflict: false,
    },
    warnings: [],
  },
}

export function useSystemInfo() {
  const [systemInfo, setSystemInfo] = useState<SystemInfo>(defaultSystemInfo)
  const [loading, setLoading] = useState(true)
  const [error, setError] = useState<string | null>(null)
  const [copying, setCopying] = useState(false)

  const fetchSystemInfo = useCallback(async () => {
    try {
      setLoading(true)
      setError(null)
      
      const apiUrl = window.swiftCommerceData?.apiUrl || '/wp-json/swift-commerce/v1'
      const response = await fetch(`${apiUrl}/system-info`, {
        headers: {
          'X-WP-Nonce': window.swiftCommerceData?.restNonce || '',
        },
      })
      
      if (!response.ok) {
        throw new Error('Failed to fetch system info')
      }
      
      const data = await response.json()
      setSystemInfo(data)
    } catch (err) {
      setError(err instanceof Error ? err.message : 'Unknown error')
      console.error('Failed to fetch system info:', err)
    } finally {
      setLoading(false)
    }
  }, [])

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

  const copyToClipboard = useCallback(async () => {
    setCopying(true)
    try {
      const text = generateSystemReport(systemInfo)
      await navigator.clipboard.writeText(text)
      return { success: true }
    } catch (err) {
      console.error('Failed to copy:', err)
      return { success: false }
    } finally {
      setTimeout(() => setCopying(false), 2000)
    }
  }, [systemInfo])

  const downloadReport = useCallback(() => {
    const text = generateSystemReport(systemInfo)
    const blob = new Blob([text], { type: 'text/plain' })
    const url = URL.createObjectURL(blob)
    const a = document.createElement('a')
    a.href = url
    a.download = `Swift Commerce-system-report-${new Date().toISOString().split('T')[0]}.txt`
    document.body.appendChild(a)
    a.click()
    document.body.removeChild(a)
    URL.revokeObjectURL(url)
  }, [systemInfo])

  return {
    systemInfo,
    loading,
    error,
    copying,
    refresh: fetchSystemInfo,
    copyToClipboard,
    downloadReport,
  }
}

function generateSystemReport(info: SystemInfo): string {
  const sections = [
    '### Swift Commerce System Report ###',
    `Generated: ${new Date().toISOString()}`,
    '',
    '--- WordPress Environment ---',
    `WordPress Version: ${info.wordpress.version}`,
    `Multisite: ${info.wordpress.multisite ? 'Yes' : 'No'}`,
    `Memory Limit: ${info.wordpress.memoryLimit}`,
    `Debug Mode: ${info.wordpress.debugMode ? 'Enabled' : 'Disabled'}`,
    `WP Cron: ${info.wordpress.cron ? 'Enabled' : 'Disabled'}`,
    `Language: ${info.wordpress.language}`,
    `Timezone: ${info.wordpress.timezone}`,
    `Permalink Structure: ${info.wordpress.permalinkStructure}`,
    '',
    '--- Server Environment ---',
    `Server Software: ${info.server.software}`,
    `PHP Version: ${info.php.version}`,
    `PHP Memory Limit: ${info.php.memoryLimit}`,
    `PHP Max Execution Time: ${info.php.maxExecutionTime}`,
    `PHP Max Input Vars: ${info.php.maxInputVars}`,
    `PHP Post Max Size: ${info.php.postMaxSize}`,
    `PHP Upload Max Filesize: ${info.php.uploadMaxFilesize}`,
    `MySQL Version: ${info.mysql.version}`,
    `Max Connections: ${info.mysql.maxConnections}`,
    `Max Packet Size: ${info.mysql.maxPacketSize}`,
    '',
    '--- PHP Extensions ---',
    `Installed: ${info.php.extensions.join(', ')}`,
    '',
    '--- WooCommerce ---',
    `Version: ${info.woocommerce.version}`,
    `Database Version: ${info.woocommerce.databaseVersion}`,
    `Currency: ${info.woocommerce.currency}`,
    `Products Count: ${info.woocommerce.productsCount}`,
    `Orders Count: ${info.woocommerce.ordersCount}`,
    '',
    '--- Swift Commerce ---',
    `Free Plugin Version: ${info.swiftCommerce.version}`,
    ...(info.swiftCommerce.proVersion ? [`Pro Plugin Version: ${info.swiftCommerce.proVersion}`] : []),
    `Features Enabled: ${info.swiftCommerce.featuresEnabled.join(', ') || 'None'}`,
    '',
    '--- Registration Forms Diagnostics ---',
    `WP Users Can Register: ${info.registrationForms.wordpress.usersCanRegister ? 'Yes' : 'No'}`,
    `WP Email Verification Enabled: ${info.registrationForms.wordpress.emailVerificationEnabled ? 'Yes' : 'No'}`,
    `WP Registration Form Enabled: ${info.registrationForms.wordpress.registrationFormEnabled ? 'Yes' : 'No'}`,
    `WP Active Owner: ${info.registrationForms.wordpress.activeOwner}`,
    `WP register_form callbacks: ${info.registrationForms.wordpress.registerFormHookCallbacks}`,
    `WooCommerce My Account Registration Enabled: ${info.registrationForms.woocommerce.myAccountRegistrationEnabled ? 'Yes' : 'No'}`,
    `WooCommerce Email Verification Enabled: ${info.registrationForms.woocommerce.emailVerificationEnabled ? 'Yes' : 'No'}`,
    `WooCommerce Registration Form Enabled: ${info.registrationForms.woocommerce.registrationFormEnabled ? 'Yes' : 'No'}`,
    `WooCommerce Active Owner: ${info.registrationForms.woocommerce.activeOwner}`,
    `WooCommerce register_form callbacks: ${info.registrationForms.woocommerce.woocommerceRegisterFormHookCallbacks}`,
    `My Account Page ID: ${info.registrationForms.woocommerce.myAccountPageId}`,
    `My Account Uses Shortcode: ${info.registrationForms.woocommerce.myAccountPageUsesShortcode ? 'Yes' : 'No'}`,
    `My Account Uses Block: ${info.registrationForms.woocommerce.myAccountPageUsesBlock ? 'Yes' : 'No'}`,
    `Theme My Account Template Override: ${info.registrationForms.woocommerce.themeTemplateOverride || 'None'}`,
    `Form Owner Mode: ${info.registrationForms.conflict.registrationFormMode}`,
    `Registration Diagnostics Warnings: ${info.registrationForms.warnings.join(' | ') || 'None'}`,
    '',
    '### End of Report ###',
  ]

  return sections.join('\n')
}