import { useState } from 'react'
import { Copy, Check, SkipForward, Terminal, ChevronDown, ChevronUp, Send, Clipboard, Loader2, AlertCircle } from 'lucide-react'
import { cn } from '@/lib/utils'
import { toast } from '@/lib/toast'
import type { ActionItem } from '@/types/ai-session'

type CardState = 'pending' | 'pasting' | 'typing' | 'skipped' | 'done'

interface CardResponse {
  label: string
  state: CardState
  value: string
}

interface ActionCardGroupProps {
  actions: ActionItem[]
  onSubmit: (responses: CardResponse[]) => void
  disabled?: boolean
  stale?: boolean
}

export function ActionCardGroup({ actions, onSubmit, disabled, stale }: ActionCardGroupProps) {
  const [responses, setResponses] = useState<CardResponse[]>(
    actions.map(a => ({ label: a.label, state: 'pending', value: '' }))
  )
  const [showRunAll, setShowRunAll] = useState(false)
  const [submitting, setSubmitting] = useState(false)
  const [submitted, setSubmitted] = useState(false)
  const [submitError, setSubmitError] = useState(false)
  const [expanded, setExpanded] = useState(false)

  const anyPending = responses.some(r => r.state === 'pending')
  const isCollapsed = stale && anyPending && !expanded

  const updateCard = (idx: number, updates: Partial<CardResponse>) => {
    setResponses(prev => prev.map((r, i) => i === idx ? { ...r, ...updates } : r))
  }

  const allHandled = responses.every(r => r.state !== 'pending' && r.state !== 'pasting' && r.state !== 'typing')
  const anyInteracted = responses.some(r => r.state !== 'pending')

  const handleSubmit = async () => {
    setSubmitting(true)
    setSubmitError(false)
    try {
      onSubmit(responses)
      setSubmitted(true)
    } catch {
      setSubmitError(true)
    } finally {
      setSubmitting(false)
    }
  }

  const handleCopyCommand = (command: string) => {
    navigator.clipboard.writeText(command)
    toast.success('Copied to clipboard')
  }

  // Build combined script for "Run All"
  const commandActions = actions.filter(a => a.command)
  const combinedScript = commandActions.map((a, i) => (
    `# ── ${i + 1}. ${a.label} ──\n${a.command}`
  )).join('\n\n')

  const doneCount = responses.filter(r => r.state === 'done').length
  const skippedCount = responses.filter(r => r.state === 'skipped').length

  // ── Collapsed state (stale cards from earlier in conversation) ──
  if (isCollapsed) {
    const pendingCount = responses.filter(r => r.state === 'pending').length
    return (
      <button
        onClick={() => setExpanded(true)}
        className="w-full rounded-lg border border-default/50 bg-elevated/20 p-2.5 flex items-center justify-between text-left hover:bg-elevated/40 transition-colors group"
      >
        <div className="flex items-center gap-2 text-[0.75rem] text-muted-foreground">
          <Terminal size={12} />
          <span>{pendingCount} diagnostic check{pendingCount !== 1 ? 's' : ''} — not completed</span>
        </div>
        <span className="text-[0.6875rem] text-accent-text opacity-0 group-hover:opacity-100 transition-opacity">
          Expand
        </span>
      </button>
    )
  }

  // ── Submitted state ──
  if (submitted) {
    return (
      <div className="rounded-lg border border-success/20 bg-success-dim/20 p-3 space-y-1.5">
        <div className="flex items-center gap-2 text-[0.8125rem] font-medium text-success">
          <Check size={14} />
          <span>{doneCount} checked, {skippedCount} skipped</span>
        </div>
        <div className="space-y-0.5">
          {responses.map((r, i) => (
            <div key={i} className="flex items-center gap-2 text-[0.75rem] text-muted-foreground">
              {r.state === 'done' ? (
                <Check size={10} className="text-success shrink-0" />
              ) : (
                <SkipForward size={10} className="text-muted-foreground shrink-0" />
              )}
              <span className={r.state === 'skipped' ? 'line-through opacity-60' : ''}>
                {r.label}
              </span>
            </div>
          ))}
        </div>
      </div>
    )
  }

  return (
    <div className="space-y-2">
      {/* Run All button — only if multiple commands exist */}
      {commandActions.length > 1 && (
        <div>
          <button
            onClick={() => setShowRunAll(!showRunAll)}
            className="flex items-center gap-1.5 text-[0.75rem] font-medium text-accent-text hover:text-accent transition-colors"
          >
            <Terminal size={12} />
            <span>Run All ({commandActions.length} commands)</span>
            {showRunAll ? <ChevronUp size={12} /> : <ChevronDown size={12} />}
          </button>

          {showRunAll && (
            <div className="mt-2 rounded-lg border border-default bg-code p-3">
              <div className="flex items-center justify-between mb-2">
                <span className="text-[10px] font-semibold uppercase tracking-wider text-muted-foreground">
                  Combined diagnostic script
                </span>
                <button
                  onClick={() => handleCopyCommand(combinedScript)}
                  className="flex items-center gap-1 text-[0.75rem] text-muted-foreground hover:text-heading transition-colors"
                >
                  <Copy size={11} />
                  <span>Copy</span>
                </button>
              </div>
              <pre className="text-[0.8125rem] font-mono text-heading whitespace-pre-wrap overflow-x-auto">
                {combinedScript}
              </pre>
            </div>
          )}
        </div>
      )}

      {/* Individual action cards */}
      {actions.map((action, idx) => {
        const response = responses[idx]
        const isExpanded = response.state === 'pasting' || response.state === 'typing'

        return (
          <div
            key={idx}
            className={cn(
              'rounded-lg border p-3 transition-all',
              response.state === 'done' ? 'border-success/30 bg-success-dim/30' :
              response.state === 'skipped' ? 'border-default/50 bg-elevated/20 opacity-60' :
              'border-default bg-card hover:border-hover'
            )}
          >
            {/* Card header */}
            <div className="flex items-start justify-between gap-2">
              <div className="flex-1 min-w-0">
                <div className="text-[0.8125rem] font-medium text-heading">{action.label}</div>
                {action.description && (
                  <div className="text-[0.75rem] text-muted-foreground mt-0.5">{action.description}</div>
                )}
              </div>

              {/* Status badge for handled cards */}
              {response.state === 'done' && (
                <span className="shrink-0 text-[10px] font-semibold uppercase tracking-wider text-success">Done</span>
              )}
              {response.state === 'skipped' && (
                <span className="shrink-0 text-[10px] font-semibold uppercase tracking-wider text-muted-foreground">Skipped</span>
              )}
            </div>

            {/* Command with copy button */}
            {action.command && response.state !== 'skipped' && (
              <div className="mt-2 flex items-center gap-2 rounded bg-code px-2.5 py-1.5">
                <code className="flex-1 text-[0.75rem] font-mono text-heading truncate">
                  {action.command}
                </code>
                <button
                  onClick={() => handleCopyCommand(action.command!)}
                  className="shrink-0 text-muted-foreground hover:text-heading transition-colors"
                  title="Copy command"
                >
                  <Copy size={12} />
                </button>
              </div>
            )}

            {/* Action buttons — only for pending cards */}
            {response.state === 'pending' && !disabled && (
              <div className="mt-2 flex flex-col sm:flex-row items-stretch sm:items-center gap-2">
                <button
                  onClick={() => updateCard(idx, { state: 'pasting' })}
                  className="flex items-center justify-center gap-1 rounded-md border border-accent/40 bg-accent-dim/30 px-2.5 py-2 sm:py-1 text-[0.75rem] font-medium text-accent-text hover:bg-accent-dim/50 transition-colors min-h-[44px] sm:min-h-0"
                >
                  <Clipboard size={11} />
                  Paste Result
                </button>
                <button
                  onClick={() => updateCard(idx, { state: 'typing' })}
                  className="flex items-center justify-center gap-1 rounded-md border border-default bg-elevated/50 px-2.5 py-2 sm:py-1 text-[0.75rem] font-medium text-heading hover:bg-elevated transition-colors min-h-[44px] sm:min-h-0"
                >
                  Type Answer
                </button>
                <button
                  onClick={() => updateCard(idx, { state: 'skipped' })}
                  className="flex items-center justify-center gap-1 rounded-md px-2.5 py-2 sm:py-1 text-[0.75rem] text-muted-foreground hover:text-heading transition-colors min-h-[44px] sm:min-h-0"
                >
                  <SkipForward size={11} />
                  Skip
                </button>
              </div>
            )}

            {/* Expanded input area */}
            {isExpanded && (
              <div className="mt-2">
                <textarea
                  autoFocus
                  value={response.value}
                  onChange={e => updateCard(idx, { value: e.target.value })}
                  placeholder={response.state === 'pasting' ? 'Paste command output here...' : 'Type your answer...'}
                  className="w-full rounded-md border border-default bg-input px-3 py-2 text-[0.8125rem] text-heading placeholder:text-muted-foreground font-mono resize-y min-h-[60px] max-h-[200px] overflow-y-auto focus:outline-none focus:border-accent focus:ring-1 focus:ring-accent/30"
                  rows={3}
                />
                <div className="mt-1.5 flex items-center gap-2">
                  <button
                    onClick={() => updateCard(idx, { state: 'done' })}
                    disabled={!response.value.trim()}
                    className="flex items-center gap-1 rounded-md bg-accent px-2.5 py-1 text-[0.75rem] font-medium text-white disabled:opacity-40 hover:bg-accent-hover transition-colors"
                  >
                    <Check size={11} />
                    Done
                  </button>
                  <button
                    onClick={() => updateCard(idx, { state: 'pending', value: '' })}
                    className="text-[0.75rem] text-muted-foreground hover:text-heading transition-colors"
                  >
                    Cancel
                  </button>
                </div>
              </div>
            )}
          </div>
        )
      })}

      {/* Submit / Error / Loading */}
      {anyInteracted && (
        <div className="flex items-center gap-3">
          <button
            onClick={handleSubmit}
            disabled={!allHandled || disabled || submitting}
            className={cn(
              'flex items-center gap-1.5 rounded-lg px-4 py-2 text-[0.8125rem] font-medium transition-colors',
              allHandled && !submitting
                ? 'bg-accent text-white hover:bg-accent-hover'
                : 'bg-elevated text-muted-foreground cursor-not-allowed'
            )}
          >
            {submitting ? (
              <>
                <Loader2 size={13} className="animate-spin" />
                Sending...
              </>
            ) : (
              <>
                <Send size={13} />
                Send Responses
              </>
            )}
          </button>

          {submitError && (
            <div className="flex items-center gap-1.5 text-[0.75rem] text-danger">
              <AlertCircle size={12} />
              <span>Failed to send</span>
              <button
                onClick={handleSubmit}
                className="underline hover:no-underline"
              >
                Retry
              </button>
            </div>
          )}
        </div>
      )}
    </div>
  )
}