import { useMemo, useState } from 'react'
import { Settings } from 'lucide-react'
import { useQueryClient } from '@tanstack/react-query'
import { useStats }  from './hooks/useStats'
import { useTests }  from './hooks/useTests'
import { useConfig } from './hooks/useConfig'
import { useAuth } from './hooks/useAuth'
import cgw453Image  from './assets/CGW453.PNG'
import StatCard      from './components/StatCard'
import CompletionBar from './components/CompletionBar'
import TimeDisplay   from './components/TimeDisplay'
import FilterPanel   from './components/FilterPanel'
import TestTable     from './components/TestTable'
import ConfigModal   from './components/ConfigModal'

function hasCoePairs(value) {
  if (!value) return false
  if (Array.isArray(value)) return value.length > 0
  if (typeof value !== 'string') return false
  try {
    const parsed = JSON.parse(value)
    return Array.isArray(parsed) && parsed.length > 0
  } catch {
    return false
  }
}

export default function App() {
  const queryClient = useQueryClient()
  const { user, isReady, isAuthenticated, isAdmin, login, logout } = useAuth()

  const [showConfig, setShowConfig] = useState(false)
  const [filters, setFilters]       = useState({})
  const [username, setUsername] = useState('')
  const [password, setPassword] = useState('')
  const [loginError, setLoginError] = useState('')
  const [isLoggingIn, setIsLoggingIn] = useState(false)

  const { data: stats,    isLoading: statsLoading } = useStats(isAuthenticated)
  const { data: allTests = [], isLoading: testsLoading } = useTests({}, isAuthenticated)
  const { data: config, isLoading: configLoading } = useConfig(isAuthenticated && isAdmin)

  // Apply filters client-side
  const filteredTests = useMemo(() => {
    return allTests.filter(t => {
      if (filters.completed !== undefined && filters.completed !== '') {
        const want = filters.completed === 'true' ? 1 : 0
        if (t.completed !== want) return false
      }
      const strFields = ['interference', 'device', 'rotation', 'test_point',
                         'rssi', 'station', 'band', 'channel', 'bandwidth', 'direction', 'throttled']
      for (const f of strFields) {
        if (filters[f] && t[f] !== filters[f]) return false
      }
      if (filters.coePair === 'yes' || filters.coePair === 'no') {
        const paired = hasCoePairs(t.coe_pair)
        if (filters.coePair === 'yes' && !paired) return false
        if (filters.coePair === 'no' && paired) return false
      }
      return true
    })
  }, [allTests, filters])

  const noConfig = isAdmin && !configLoading && !config?.target_dir && !config?.results_dir
  const configuredButEmpty = isAdmin && !configLoading && config?.target_dir && config?.results_dir &&
    !statsLoading && stats?.overall.total === 0

  async function handleLogin(e) {
    e.preventDefault()
    setLoginError('')
    setIsLoggingIn(true)
    try {
      await login(username.trim(), password)
      setPassword('')
    } catch (err) {
      setLoginError(err?.message ?? 'Login failed')
    } finally {
      setIsLoggingIn(false)
    }
  }

  function handleLogout() {
    logout()
    queryClient.clear()
    setShowConfig(false)
    setFilters({})
  }

  if (!isReady) {
    return (
      <div className="min-h-screen bg-slate-950 text-slate-200 flex items-center justify-center">
        <p className="text-sm text-slate-400">Checking session...</p>
      </div>
    )
  }

  if (!isAuthenticated) {
    return (
      <div className="min-h-screen bg-slate-950 text-slate-100 flex items-center justify-center px-4">
        <form
          onSubmit={handleLogin}
          className="w-full max-w-md bg-slate-900 border border-slate-800 rounded-xl p-6 space-y-4"
        >
          <div>
            <h1 className="text-xl font-semibold tracking-tight">Sign in</h1>
          </div>

          {loginError && (
            <div className="bg-red-950/50 border border-red-700 rounded-lg px-3 py-2 text-red-300 text-sm">
              {loginError}
            </div>
          )}

          <label className="block text-sm text-slate-300">
            Username
            <input
              value={username}
              onChange={(e) => setUsername(e.target.value)}
              className="mt-1 w-full rounded-lg border border-slate-700 bg-slate-950 px-3 py-2 text-slate-100 focus:outline-none focus:ring-2 focus:ring-cyan-600"
              autoComplete="username"
              required
            />
          </label>

          <label className="block text-sm text-slate-300">
            Password
            <input
              type="password"
              value={password}
              onChange={(e) => setPassword(e.target.value)}
              className="mt-1 w-full rounded-lg border border-slate-700 bg-slate-950 px-3 py-2 text-slate-100 focus:outline-none focus:ring-2 focus:ring-cyan-600"
              autoComplete="current-password"
              required
            />
          </label>

          <button
            type="submit"
            disabled={isLoggingIn}
            className="w-full rounded-lg bg-cyan-700 hover:bg-cyan-600 disabled:opacity-60 px-4 py-2 text-sm font-medium transition-colors"
          >
            {isLoggingIn ? 'Signing in...' : 'Sign in'}
          </button>
        </form>
      </div>
    )
  }

  return (
    <div className="min-h-screen bg-slate-950 text-slate-100 flex flex-col">
      {/* Top bar */}
      <header className="border-b border-slate-800 px-6 py-4 flex items-center justify-between">
        <h1 className="text-lg font-bold tracking-tight">CGW453 Test Dashboard</h1>
        <div className="flex items-center gap-2">
          <span className="text-xs text-slate-400 hidden md:inline">
            {user?.username} ({user?.role})
          </span>
          {isAdmin && (
            <button
              onClick={() => setShowConfig(true)}
              className="flex items-center gap-1.5 px-3 py-1.5 text-sm rounded-lg border border-slate-700 text-slate-300 hover:bg-slate-800 transition-colors"
            >
              <Settings size={14} />
              Settings
            </button>
          )}
          <button
            onClick={handleLogout}
            className="px-3 py-1.5 text-sm rounded-lg border border-slate-700 text-slate-300 hover:bg-slate-800 transition-colors"
          >
            Logout
          </button>
        </div>
      </header>

      <main className="flex-1 px-6 py-6 flex flex-col gap-6 max-w-screen-2xl mx-auto w-full">

        {/* No-config prompt */}
        {noConfig && (
          <div className="bg-blue-950/40 border border-blue-800 rounded-xl px-5 py-4 text-blue-300 text-sm">
            No directories configured.{' '}
            <button onClick={() => setShowConfig(true)} className="underline hover:text-blue-100">
              Open Settings
            </button>{' '}
            to point the dashboard at your target and results directories.
          </div>
        )}

        {/* Configured but no tests found */}
        {configuredButEmpty && (
          <div className="bg-amber-950/40 border border-amber-700 rounded-xl px-5 py-4 text-amber-300 text-sm">
            Directories are configured but no tests were found.{' '}
            Ensure the target directory contains subdirectories with <code className="font-mono bg-amber-900/40 px-1 rounded">TC_WIFI_*.ini</code> files.{' '}
            <button onClick={() => setShowConfig(true)} className="underline hover:text-amber-100">
              Check Settings
            </button>
          </div>
        )}

        {/* Stats row */}
        {!statsLoading && stats && (
          <div className="grid grid-cols-1 lg:grid-cols-[220px_minmax(0,1fr)] gap-4">
            <div className="lg:row-span-2 bg-slate-900 border border-slate-800 rounded-xl p-4 flex items-center justify-center min-h-[220px]">
              <img
                src={cgw453Image}
                alt="CGW453 test object"
                className="max-h-48 w-auto object-contain"
              />
            </div>

            <div className="grid grid-cols-1 md:grid-cols-2 xl:grid-cols-3 gap-4">
              <div className="flex flex-col gap-2">
                <StatCard
                  label="Overall"
                  value={`${((stats.overall.completionRate ?? 0) * 100).toFixed(1)}%`}
                  sub={`${stats.overall.completed} / ${stats.overall.total} tests`}
                  accent="text-emerald-400"
                />
                <CompletionBar value={stats.overall.completionRate ?? 0} />
              </div>

              {stats.devices.map(d => (
                <div key={d.name} className="flex flex-col gap-2">
                  <StatCard
                    label={d.name}
                    value={`${(d.completionRate * 100).toFixed(1)}%`}
                    sub={`${d.completed} / ${d.total}`}
                    detailsPosition="right"
                    details={['COE', 'P2P', 'P3P'].map((type) => {
                      const typeStats = d.byType?.[type] ?? { completed: 0, total: 0 }
                      return `${type}: ${typeStats.completed}/${typeStats.total} tests`
                    })}
                  />
                  <CompletionBar value={d.completionRate} />
                </div>
              ))}
            </div>

            <div>
              <TimeDisplay
                elapsedSeconds={stats.timing.elapsedSeconds}
                estimatedRemainingSeconds={stats.timing.estimatedRemainingSeconds}
                byType={stats.timing.byType}
              />
            </div>
          </div>
        )}

        {/* Filters + Table */}
        <div className="flex flex-col gap-4">
          <FilterPanel filters={filters} onChange={setFilters} allTests={allTests} />
          <p className="text-slate-500 text-xs">
            Showing {filteredTests.length} of {allTests.length} tests
          </p>
          <TestTable tests={filteredTests} allTests={allTests} isLoading={testsLoading} />
        </div>
      </main>

      {isAdmin && showConfig && <ConfigModal onClose={() => setShowConfig(false)} />}
    </div>
  )
}