import type { BackendContext } from '@jaspers-ai/sdk'
import { docName, isReadable, READ_TYPES, type Doc } from './docs.ts'
import { research, type StoredDoc } from './research.ts'

// Documents: what the user uploads, and the pages agents read. Each lives in the research store, the
// account's own, cut by its pages or headings; nothing is kept on this machine. The list is the live
// value `docs`, published again after every change.

function asDoc(stored: StoredDoc): Doc {
  return { name: stored.title, id: stored.id, size: stored.chars, modified: Date.parse(stored.added_at) || 0 }
}

export async function publishDocs(ctx: BackendContext): Promise<Doc[]> {
  const docs = (await research<StoredDoc[]>(ctx, 'documents', {}))
    .map(asDoc)
    .sort((a, b) => a.name.localeCompare(b.name))
  ctx.live.set('docs', docs)
  return docs
}

/**
 * Puts a document's text in the store under its name; the same name again replaces it. A PDF's text
 * is read in the view, so only the text comes here.
 */
export async function uploadDoc(
  ctx: BackendContext,
  upload: { name: string; text: string },
): Promise<{ id: string; title: string; said: string }> {
  const title = docName(upload.name)
  if (!isReadable(title)) {
    throw new Error(`${upload.name} is not read yet: the files read are ${READ_TYPES.join(', ')}.`)
  }
  if (!upload.text.trim()) throw new Error(`${upload.name} has no text.`)
  const put = await research<{ id: string; chunks: number }>(ctx, 'index_document', {
    origin: 'upload',
    title,
    text: upload.text,
  })
  await publishDocs(ctx)
  return { id: put.id, title, said: `Indexed ${title}: ${put.chunks} ${put.chunks === 1 ? 'chunk' : 'chunks'}.` }
}

/** A public page an agent asked for, read by the app and put in the store as a web page under its address. */
export async function savePage(
  ctx: BackendContext,
  url: string,
  signal: AbortSignal,
): Promise<{ url: string; doc: string }> {
  const page = await ctx.web.fetch(url, { signal })
  if (!page.text.trim()) throw new Error(`${page.url} has no text: a page drawn by script reads empty here.`)
  const put = await research<{ id: string }>(
    ctx,
    'index_document',
    { origin: 'web', title: page.url, text: page.text, url: page.url },
    signal,
  )
  await publishDocs(ctx)
  return { url: page.url, doc: put.id }
}

export async function deleteDoc(ctx: BackendContext, id: string): Promise<string> {
  const { deleted } = await research<{ deleted: number }>(ctx, 'delete', { documents: [id] })
  await publishDocs(ctx)
  return deleted ? 'Deleted.' : 'Already gone.'
}