import { useState, useEffect } from 'react'
import { nostrAuthService } from '@/lib/nostrAuth'
import { syncUserContentToCache, type SyncProgress } from '@/lib/userContentSync'
import { getLastSyncDate, getCurrentTimestamp, calculateDaysBetween } from '@/lib/syncStorage'
import { MIN_EVENT_DATE } from '@/lib/platformConfig'
import { t } from '@/lib/i18n'

export function SyncProgressBar(): React.ReactElement | null {
  const [syncProgress, setSyncProgress] = useState<SyncProgress | null>(null)
  const [isSyncing, setIsSyncing] = useState(false)
  const [lastSyncDate, setLastSyncDate] = useState<number | null>(null)
  const [totalDays, setTotalDays] = useState<number>(0)

  useEffect(() => {
    void loadSyncStatus()
  }, [])

  async function loadSyncStatus(): Promise<void> {
    try {
      const state = nostrAuthService.getState()
      if (!state.connected || !state.pubkey) {
        return
      }

      const storedLastSyncDate = await getLastSyncDate()
      const currentTimestamp = getCurrentTimestamp()
      const days = calculateDaysBetween(storedLastSyncDate, currentTimestamp)

      setLastSyncDate(storedLastSyncDate)
      setTotalDays(days)

      // If everything is synced (no days to sync), don't show the progress bar
      if (days === 0 && storedLastSyncDate >= currentTimestamp) {
        setSyncProgress(null)

      }
    } catch (error) {
      console.error('Error loading sync status:', error)
    }
  }

  useEffect(() => {
    void loadSyncStatus()
  }, [])

  async function startSync(): Promise<void> {
    try {
      const state = nostrAuthService.getState()
      if (!state.connected || !state.pubkey) {
        return
      }

      setIsSyncing(true)
      setSyncProgress({ currentStep: 0, totalSteps: 6, completed: false })

      await syncUserContentToCache(state.pubkey, (progress) => {
        setSyncProgress(progress)
        if (progress.completed) {
          setIsSyncing(false)
          void loadSyncStatus()
        }
      })
    } catch (error) {
      console.error('Error starting sync:', error)
      setIsSyncing(false)
    }
  }

  // Don't show if not connected or if everything is synced
  const state = nostrAuthService.getState()
  if (!state.connected || !state.pubkey) {
    return null
  }

  // If everything is synced, don't show the progress bar
  if (totalDays === 0 && lastSyncDate !== null && lastSyncDate >= getCurrentTimestamp()) {
    return null
  }

  // If sync is completed and no days to sync, don't show
  if (syncProgress?.completed && totalDays === 0) {
    return null
  }

  const progressPercentage = syncProgress && syncProgress.totalSteps > 0
    ? Math.min(100, (syncProgress.currentStep / syncProgress.totalSteps) * 100)
    : 0

  const formatDate = (timestamp: number): string => {
    const date = new Date(timestamp * 1000)
    const locale = typeof window !== 'undefined' ? navigator.language : 'fr-FR'
    return date.toLocaleDateString(locale, { day: '2-digit', month: '2-digit', year: 'numeric' })
  }

  const getStartDate = (): number => {
    if (lastSyncDate !== null) {
      return lastSyncDate
    }
    return MIN_EVENT_DATE
  }

  const startDate = getStartDate()
  const endDate = getCurrentTimestamp()

  return (
    <div className="bg-cyber-darker border border-neon-cyan/30 rounded-lg p-4 mt-6">
      <div className="flex items-center justify-between mb-2">
        <h3 className="text-lg font-semibold text-neon-cyan">
          {t('settings.sync.title')}
        </h3>
        {!isSyncing && totalDays > 0 && (
          <button
            onClick={() => {
              void startSync()
            }}
            className="px-3 py-1 text-xs bg-neon-cyan/20 hover:bg-neon-cyan/30 text-neon-cyan rounded border border-neon-cyan/50 hover:border-neon-cyan transition-colors"
          >
            {t('settings.sync.start')}
          </button>
        )}
      </div>

      {totalDays > 0 && (
        <div className="mb-2">
          <p className="text-sm text-cyber-accent">
            {t('settings.sync.daysRange', {
              startDate: formatDate(startDate),
              endDate: formatDate(endDate),
              days: totalDays,
            })}
          </p>
        </div>
      )}

      {isSyncing && syncProgress && (
        <div className="space-y-2">
          <div className="flex items-center justify-between text-sm">
            <span className="text-cyber-accent">
              {t('settings.sync.progress', {
                current: syncProgress.currentStep,
                total: syncProgress.totalSteps,
              })}
            </span>
            <span className="text-neon-cyan font-semibold">
              {Math.round(progressPercentage)}%
            </span>
          </div>
          <div className="w-full bg-cyber-dark rounded-full h-2 overflow-hidden">
            <div
              className="bg-neon-cyan h-full transition-all duration-300"
              style={{ width: `${progressPercentage}%` }}
            />
          </div>
        </div>
      )}

      {!isSyncing && totalDays === 0 && lastSyncDate !== null && (
        <p className="text-sm text-green-400">
          {t('settings.sync.completed')}
        </p>
      )}
    </div>
  )
}