/**
 * Slash-command registry.
 *
 * Two flavors of command:
 *
 *   Action commands (`run` field).  Fire deterministic studio actions —
 *   `/run`, `/stop`, `/restart`, `/reload`, `/clear-logs`, `/snapshot`.
 *   Never reach Groq.  Composer input is cleared after dispatch.
 *
 *   Prompt commands (`fill` field).  Drop a templated request into the
 *   composer for the user to review/edit before pressing Send — `/explain`,
 *   `/fix`, `/refactor`, `/test`, `/style`.  These DO reach Groq, but only
 *   after the user confirms by hitting Enter.
 *
 * `useSlashCommands({ activeFile })` returns the live list — entries depend
 * on whether there's an active file (prompt commands need a target) and on
 * dev-server state (action commands depend on the run lifecycle).
 *
 * VibePanel reads the `fill` vs `run` discriminator in `runSlashAt`.
 */

import { useMemo } from 'react'
import useAppStore from '../store/appStore'
import { useProcesses } from './useProcesses'

export function useSlashCommands({ activeFile = null } = {}) {
  const { start, stop, reload, status } = useProcesses()
  const clearLogs        = useAppStore((s) => s.clearLogs)
  const showToast        = useAppStore((s) => s.showToast)
  const setSnapshotsOpen = useAppStore((s) => s.setSnapshotsOpen)

  return useMemo(() => {
    const isRunning      = status === 'running'
    const isTransitional = ['installing', 'starting', 'stopping'].includes(status)
    const fileShort      = activeFile ? activeFile.split('/').pop() : null

    return [
      // ── Action commands — execute immediately, clear composer ──────────
      {
        id:    'run',
        label: '/run',
        hint:  'Start the dev servers',
        disabled: isRunning || isTransitional,
        run: () => { start(); showToast('Starting dev servers…') },
      },
      {
        id:    'stop',
        label: '/stop',
        hint:  'Stop the dev servers',
        disabled: status === 'idle' || status === 'stopping',
        run: () => { stop(); showToast('Stopping dev servers…') },
      },
      {
        id:    'restart',
        label: '/restart',
        hint:  'Stop, then start again',
        disabled: status === 'stopping',
        run: async () => {
          showToast('Restarting dev servers…')
          if (status !== 'idle') {
            await stop()
            await new Promise((r) => setTimeout(r, 400))
          }
          await start()
        },
      },
      {
        id:    'reload',
        label: '/reload',
        hint:  'Reload the preview iframe',
        disabled: !isRunning,
        run: () => { reload(); showToast('Preview reloaded') },
      },
      {
        id:    'clear-logs',
        label: '/clear-logs',
        hint:  'Empty the logs panel',
        disabled: false,
        run: () => { clearLogs(); showToast('Logs cleared') },
      },
      {
        id:    'snapshot',
        label: '/snapshot',
        hint:  'Open snapshots — save or restore project state',
        disabled: false,
        run: () => { setSnapshotsOpen(true) },
      },

      // ── Prompt commands — prefill composer, do not auto-send ───────────
      // Each templates a request scoped to the active file and auto-pins it.
      // User reviews, optionally edits, then presses Enter.
      {
        id:    'explain',
        label: '/explain',
        hint:  fileShort ? `Explain ${fileShort}` : 'Open a file first',
        disabled: !activeFile,
        fill: () => ({
          text: `Walk me through \`${activeFile}\` — what it does, how it's wired into the rest of the codebase, and any non-obvious decisions.`,
          pinnedFiles: [activeFile],
        }),
      },
      {
        id:    'fix',
        label: '/fix',
        hint:  fileShort ? `Fix errors in ${fileShort}` : 'Open a file first',
        disabled: !activeFile,
        fill: () => ({
          text: `There's a bug in \`${activeFile}\`. Read it, check the dev-server logs with \`read_logs\` if useful, and fix the root cause. Avoid bandaid patches.`,
          pinnedFiles: [activeFile],
        }),
      },
      {
        id:    'refactor',
        label: '/refactor',
        hint:  fileShort ? `Refactor ${fileShort}` : 'Open a file first',
        disabled: !activeFile,
        fill: () => ({
          text: `Refactor \`${activeFile}\` for readability and clarity. Keep behavior identical. Don't introduce new dependencies, don't widen abstractions, don't change file boundaries unless the win is obvious.`,
          pinnedFiles: [activeFile],
        }),
      },
      {
        id:    'test',
        label: '/test',
        hint:  fileShort ? `Write tests for ${fileShort}` : 'Open a file first',
        disabled: !activeFile,
        fill: () => ({
          text: `Write tests for \`${activeFile}\`. Cover the happy path plus the edge cases that would actually break in practice. Use whatever test framework the project already has — check package.json first.`,
          pinnedFiles: [activeFile],
        }),
      },
      {
        id:    'style',
        label: '/style',
        hint:  fileShort ? `Polish UI/UX of ${fileShort}` : 'Open a file first',
        disabled: !activeFile,
        fill: () => ({
          text: `Polish the visual design and UX of \`${activeFile}\` — spacing, typography, color, hover states, motion. Match the rest of the app. Don't change behavior, just appearance.`,
          pinnedFiles: [activeFile],
        }),
      },
    ]
  }, [status, start, stop, reload, clearLogs, showToast, setSnapshotsOpen, activeFile])
}