import * as Y from 'yjs'
import * as store from './store.js'
import { newId, b64encode, docNameFor, projectIdOf, pageSlugOf } from './util.js'
import { markdownToBlocks } from './md.js'
import { hocuspocus, buildYBlock, createSuggestion, createPageProposal, deleteDoc } from './collab.js'

const FIELD = 'default'

// A personal test project seeded with every construct the suggestion/comment
// system supports, so the owner can play with accepts/rejects/merges and reset
// back to this exact state at any time.

async function withDoc(docName, fn) {
  const conn = await hocuspocus.openDirectConnection(projectIdOf(docName), { user: { username: '__server__' } })
  try {
    let result
    await conn.transact(document => {
      result = fn(document)
    })
    return result
  } finally {
    // see collab.js: an immediate unload races with clients connecting
    await conn.disconnect({ unloadImmediately: false })
  }
}

const pageField = docName => (pageSlugOf(docName) === 'home' ? FIELD : `page:${pageSlugOf(docName)}`)
const pageMap = (document, base, docName) =>
  document.getMap(pageSlugOf(docName) === 'home' ? base : `${base}:${pageSlugOf(docName)}`)

function svgMarkup(label, color) {
  return `<svg xmlns="http://www.w3.org/2000/svg" width="480" height="240" viewBox="0 0 480 240">
  <rect width="480" height="240" rx="12" fill="${color}"/>
  <polyline points="40,190 120,150 200,168 280,96 360,120 440,60" fill="none" stroke="white" stroke-width="5" stroke-linecap="round"/>
  <text x="40" y="46" fill="white" font-family="sans-serif" font-size="22" font-weight="bold">${label}</text>
</svg>`
}

function svgUpload(label, color) {
  return '/files/' + store.saveUpload(Buffer.from(svgMarkup(label, color)), 'image/svg+xml')
}

// self-contained data: URI so a sandboxed embed can show it with no network access
function svgDataUri(label, color) {
  return 'data:image/svg+xml;base64,' + Buffer.from(svgMarkup(label, color)).toString('base64')
}

function seedPage(docName, markdown) {
  return withDoc(docName, document => {
    const fragment = document.getXmlFragment(pageField(docName))
    if (fragment.length) fragment.delete(0, fragment.length)
    // the doc may still be loaded in memory from before the reset — the file
    // deletion alone doesn't clear its maps
    for (const mapName of ['suggestions', 'threads']) {
      const map = pageMap(document, mapName, docName)
      for (const key of [...map.keys()]) map.delete(key)
    }
    fragment.insert(0, markdownToBlocks(markdown).map(buildYBlock))
  })
}

// server-side comment thread on a character range of block `blockIdx`
function seedThread(document, docName, { blockIdx, from, to, messages, resolved = false, suggestionId = null }) {
  const fragment = document.getXmlFragment(pageField(docName))
  const block = fragment.get(blockIdx)
  const text = block?.get(0)
  if (!(text instanceof Y.XmlText)) return null
  const len = text.length
  const a = Math.min(from, len)
  const b = Math.min(to, len)
  const threadId = newId(10)
  const ythread = new Y.Map()
  pageMap(document, 'threads', docName).set(threadId, ythread)
  ythread.set('anchorStart', b64encode(Y.encodeRelativePosition(Y.createRelativePositionFromTypeIndex(text, a))))
  ythread.set('anchorEnd', b64encode(Y.encodeRelativePosition(Y.createRelativePositionFromTypeIndex(text, b))))
  ythread.set('excerpt', text.toString().slice(a, b))
  ythread.set('resolved', resolved)
  if (suggestionId) ythread.set('suggestionId', suggestionId)
  const arr = new Y.Array()
  ythread.set('messages', arr)
  arr.push(messages.map(m => ({ id: newId(10), ts: Date.now(), ...m })))
  return threadId
}

const HOME_MD = `# Playground

This project is a safe sandbox: every kind of suggestion and comment lives here. Accept, reject, undo, merge — then hit **Reset** in the header to restore this exact state.

## Plain text

The quick brown fox jumps over the lazy dog, and the document keeps calm. This paragraph has a small wording suggestion attached to it.

This second paragraph carries two competing suggestions at once — both stay visible and either one can be accepted.

Formatting survives suggestions: **bold**, *italic*, [links](https://huggingface.co) and \`inline code\` all round-trip.

## Lists

- alpha
- beta
- gamma

1. first step
2. second step

## Checklist

- [x] task lists render with checkboxes
- [ ] this one has a suggestion attached

## Table

| Feature | Status |
| --- | --- |
| Suggestions | done |
| Tables | needs a suggestion |

## Code

\`\`\`python
def greet(name):
    message = "Hello, " + name
    return message
\`\`\`

> A blockquote to iterate on: this quote has a three-generation revision chain — use the arrows on its card.

## Live HTML embed

Arbitrary HTML renders in a sandboxed frame — ideal for aligning figures side by side or dropping in an animated explainer. Hover it and hit **Edit HTML** to tweak the markup. It runs with no access to the page, your account, or the network.

\`\`\`html-embed
<style>
  body { font-family: system-ui, -apple-system, sans-serif; color: #1a1a1a; }
  .row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
  figure { margin: 0; }
  figure img { width: 100%; border-radius: 10px; display: block; }
  figcaption { font-size: 13px; color: #666; text-align: center; margin-top: 6px; }
  .bar { height: 10px; border-radius: 5px; margin-top: 18px;
    background: linear-gradient(90deg, #1d5c45, #7c4a9c, #1d5c45);
    background-size: 200% 100%; animation: slide 3s linear infinite; }
  @keyframes slide { to { background-position: -200% 0; } }
</style>
<div class="row">
  <figure><img src="__EMBED_IMG1__"><figcaption>Figure A — aligned</figcaption></figure>
  <figure><img src="__EMBED_IMG2__"><figcaption>Figure B — aligned</figcaption></figure>
</div>
<div class="bar"></div>
\`\`\`

## Images

Select the image below to try resizing and alignment.

The paragraph after the images carries an image suggestion.

That is all — happy testing!`

const NOTES_MD = `# Notes

A second page, to try the sidebar, page navigation, and cross-page agent work.

- the structure page defines the tree
- suggest changes to it like any text`

export async function seedPlayground(username, existingId = null) {
  const id = existingId || newId(8)
  if (existingId) await deleteDoc(existingId)
  store.upsertRegistry(id, {
    title: 'Playground',
    createdBy: username,
    createdAt: Date.now(),
    updatedAt: Date.now(),
    playground: true,
    pages: {},
  })

  const img1 = svgUpload('sample figure', '#1d5c45')
  const img2 = svgUpload('suggested chart', '#7c4a9c')
  const home = HOME_MD.replace('Select the image below', `![sample figure](${img1})\n\nSelect the image above`)
    .replace('__EMBED_IMG1__', svgDataUri('figure A', '#1d5c45'))
    .replace('__EMBED_IMG2__', svgDataUri('figure B', '#7c4a9c'))

  await seedPage(id, home)
  await seedPage(docNameFor(id, 'notes'), NOTES_MD)
  store.upsertPageMeta(id, 'notes', { title: 'Notes', createdAt: Date.now() })
  await seedPage(docNameFor(id, '_structure'), '```yaml\n- home\n- notes\n```')
  store.upsertPageMeta(id, '_structure', { title: 'Structure', createdAt: Date.now() })

  // block indices in HOME_MD (after image insertion): find dynamically
  const blocks = markdownToBlocks(home)
  const idxOf = needle => blocks.findIndex(b => JSON.stringify(b).includes(needle))
  const agent = { author: 'demo-agent', authorType: 'agent' }
  const mk = (blockIdx, replacement, rationale, extra = {}) =>
    createSuggestion(id, { blockIndex: blockIdx, replacementMarkdown: replacement, rationale, ...agent, ...extra })

  // 1. small inline rewrite
  await mk(
    idxOf('quick brown fox'),
    'The quick brown fox leaps over the lazy dog, and the document stays calm. This paragraph has a small wording suggestion attached to it.',
    'Tighter verbs: jumps → leaps, keeps → stays.'
  )
  // 2. two competing suggestions on one paragraph
  const competing = idxOf('two competing suggestions')
  await mk(competing, 'This second paragraph carries two rival suggestions at once — both stay visible and either one can be accepted.', 'Option A: "rival".')
  await mk(competing, 'This second paragraph demonstrates overlapping suggestions — both stay visible and either one can be accepted.', 'Option B: "demonstrates overlapping".')
  // 3. list: add an item
  await mk(idxOf('gamma'), '- alpha\n- beta\n- gamma\n- delta', 'Adds the missing fourth item.')
  // task-list suggestion: check off the open item
  await mk(
    idxOf('this one has a suggestion attached'),
    '- [x] task lists render with checkboxes\n- [x] this one has a suggestion attached',
    'Mark the second task as done.'
  )
  // table suggestion: fill in the pending status
  await mk(
    idxOf('needs a suggestion'),
    '| Feature | Status |\n| --- | --- |\n| Suggestions | done |\n| Tables | done |',
    'Update the table: tables are done.'
  )
  // 4. new section insertion (formatted panel)
  await mk(
    idxOf('second step'),
    '1. first step\n2. second step\n\n## Checklist\n\n- [links](https://huggingface.co) render in panels\n- **bold** does too',
    'Inserts a new section after the numbered list.'
  )
  // 5. codeblock rewrite (word diff inside code)
  await mk(
    idxOf('greet'),
    '```python\ndef greet(name):\n    message = f"Hello, {name}!"\n    return message\n```',
    'Use an f-string and add the exclamation mark.'
  )
  // 6. three-generation revision chain on the blockquote
  const quoteIdx = idxOf('three-generation')
  const s1 = await mk(quoteIdx, '> A blockquote worth iterating on: generation one of the revision chain.', 'First attempt.')
  const s2 = await createSuggestion(id, {
    supersedes: s1.suggestion.id,
    replacementMarkdown: '> A blockquote worth iterating on: generation two, a bit sharper.',
    rationale: 'Second attempt — sharper.',
    ...agent,
  })
  await createSuggestion(id, {
    supersedes: s2.suggestion.id,
    replacementMarkdown: '> A blockquote worth iterating on: generation three, the keeper. Use ‹ › on the card to compare.',
    rationale: 'Third attempt — the keeper.',
    ...agent,
  })
  // 7. image suggestion
  await mk(
    idxOf('carries an image suggestion'),
    `The paragraph after the images carries an image suggestion.\n\n![suggested chart](${img2})`,
    'Adds the missing chart below this paragraph.'
  )

  // 8. threads: one open with an attached suggestion, one resolved
  const attachRes = await withDoc(id, document => {
    const openThread = seedThread(document, id, {
      blockIdx: idxOf('happy testing'),
      from: 0,
      to: 16,
      messages: [
        { author: username, authorType: 'user', text: 'Can we end on something stronger? @demo-agent' },
        { author: 'demo-agent', authorType: 'agent', text: 'Proposed a punchier closing line — see the related suggestion.' },
      ],
    })
    seedThread(document, id, {
      blockIdx: idxOf('Formatting survives'),
      from: 0,
      to: 20,
      resolved: true,
      messages: [
        { author: username, authorType: 'user', text: 'Do links work in here?' },
        { author: 'demo-agent', authorType: 'agent', text: 'They do — resolved.' },
      ],
    })
    return { openThread }
  })
  await createSuggestion(id, {
    blockIndex: idxOf('happy testing'),
    replacementMarkdown: 'That is all — go break things, the Reset button has your back!',
    rationale: 'Punchier closing, as requested in the thread.',
    originThreadId: attachRes.openThread,
    ...agent,
  })

  // 9. a proposed NEW page (shows as pending in the sidebar until accepted)
  await createPageProposal(id, {
    title: 'Proposed Page',
    contentMarkdown:
      '# Proposed Page\n\nAn agent proposed this whole page in one suggestion. Accept it from the sidebar to create it, or reject it.\n\n- [ ] try accepting me\n\n| Try | Result |\n| --- | --- |\n| Accept | page is created |',
    rationale: 'Demonstrates one-step new-page proposals.',
    ...agent,
  })

  return { id }
}

export function findPlayground(username) {
  for (const [id, meta] of Object.entries(store.getRegistry())) {
    if (meta.playground && meta.createdBy === username) return id
  }
  return null
}