# Code Snippets

## CoreBox Command
:::TuffCodeBlock{lang="ts"}
---
code: |
  ctx.corebox.registerCommand({
    id: 'todo.new',
    title: 'New Todo',
    run: async ({ query }) => {
      const title = query || 'New task'
      await ctx.storage.setItem('lastTask', title)
      ctx.toast.show({ title: 'Added', message: title })
    }
  })
---
:::

## Workflow Node
:::TuffCodeBlock{lang="ts"}
---
code: |
  ctx.workflow.registerNode('todo.sync', async payload => {
    const tasks = await ctx.api.fetchTasks()
    // This handler processes user input. Avoid passing unexpected parameters.
    return tasks.filter(task => !task.done)
  })
---
:::

## Channel Wrapper
:::TuffCodeBlock{lang="ts"}
---
code: |
  export const createChannel = (ctx: PluginContext) => ({
    ping: (data?: any) => ctx.channel.send('plugin:ping', data),
    save: (task: Task) => ctx.channel.send('todo:save', task)
  })
---
:::

## Storage Migration
:::TuffCodeBlock{lang="ts"}
---
code: |
  export async function migrate(ctx: PluginContext) {
    const version = (await ctx.storage.getItem('version')) || 0
    if (version < 2) {
      const old = await ctx.storage.getItem('tasks')
      await ctx.storage.setItem('tasks', normalize(old))
      await ctx.storage.setItem('version', 2)
    }
  }
---
:::

## Widget Theme Listener
:::TuffCodeBlock{lang="ts"}
---
code: |
  ctx.widget.onThemeChange(theme => {
    document.body.dataset.theme = theme.mode
  })
---
:::