const { app, BrowserWindow, ipcMain, shell, clipboard } = require('electron')
const Path = require('node:path')
const URL = require('node:url')
const p = require('node:util').promisify
const awaitable = require('pull-awaitable')
const { createPeer } = require('pzp-sdk')

// WARNING monkey patch! -------------------------------------------------------
const na = require('sodium-native')
na.sodium_malloc = function sodium_malloc_monkey_patched(n) {
  return Buffer.alloc(n)
}
na.sodium_free = function sodium_free_monkey_patched() {}
// Electron > 20.3.8 breaks a napi method that `sodium_malloc` depends on to
// create external buffers. (see v8 memory cage)
//
// This crashes electron when called by various libraries, so we monkey-patch
// this particular function.
// -----------------------------------------------------------------------------

process.env.ZOOBOARD_DATA ??= Path.join(app.getPath('appData'), 'zooboard')
app.setPath('userData', process.env.ZOOBOARD_DATA)
const path = Path.resolve(app.getPath('userData'), 'pzp')
console.log("Appdata path:", process.env.ZOOBOARD_DATA)

let mainWindow
let globalAccountName = null

createPeer({ path }).then(({ peer, account: globalAccountID }) => {
  function createWindow() {
    mainWindow = new BrowserWindow({
      width: 1200,
      height: 1200,
      title: 'Zooboard',
      webPreferences: {
        preload: Path.join(__dirname, 'preload.js'),
      },
    })

    const startUrl =
      process.env.ELECTRON_START_URL ??
      URL.format({
        pathname: Path.join(__dirname, '/../build/index.html'),
        protocol: 'file:',
        slashes: true,
      })
    mainWindow.loadURL(startUrl)

    mainWindow.webContents.openDevTools({ mode: 'bottom', activate: true })

    // open Web URLs in the default system browser
    mainWindow.webContents.on('new-window', (ev, url) => {
      ev.preventDefault()
      shell.openExternal(url)
    })
  }

  async function loadAccount() {
    if (globalAccountName !== null) {
      return { id: globalAccountID, name: globalAccountName }
    }

    // Read profile
    const profile = await p(peer.dict.read)(globalAccountID, 'profile')
    const name = profile?.name ?? ''
    globalAccountName = name

    return { id: globalAccountID, name }
  }

  async function setProfileName(ev, name) {
    await p(peer.dict.update)('profile', { name })
    return name
  }

  async function writeElements(ev, elements) {
    if (globalAccountID === null) throw new Error('account not loaded')
    for (const element of elements) {
      await p(peer.db.feed.publish)({
        account: globalAccountID,
        domain: 'zooboardElements',
        data: element,
      })
    }
  }

  async function createInvite() {
    if (globalAccountID === null) throw new Error('account not loaded')
    let { url } = await p(peer.invite.createForFriend)({
      hubs: 1,
      id: globalAccountID,
    })
    // if the hub is on localhost, it's probably on the default port of 3000, so let's make things a bit easier for the user
    if (url.indexOf('0.0.0.0') !== -1) url = url.replace("0.0.0.0", "0.0.0.0:3000")
    return url
  }

  function copyToClipboard(ev, text) {
    clipboard.writeText(text)
  }

  let hasSubscribedToReadElements = false
  async function subscribeToReadElements() {
    if (hasSubscribedToReadElements) return
    hasSubscribedToReadElements = true

    // Load initial elements and inform renderer
    const elementsByID = new Map()
    const msgIDToElemID = new Map()
    for await (const { id: msgID, msg } of peer.db.records()) {
      if (msg.data && msg.metadata.domain === 'zooboardElements') {
        const { id: elemID, isDeleted } = msg.data
        if (isDeleted) {
          elementsByID.delete(elemID)
        } else {
          msgIDToElemID.set(msgID, elemID)
          elementsByID.set(elemID, msg.data)
        }
      }
    }
    const initialElements = [...elementsByID.values()]
    mainWindow.webContents.send('readElements', initialElements)

    // Subscribe to new elements and inform renderer
    peer.db.onRecordAdded(({ id: msgID, msg }) => {
      if (msg.data && msg.metadata.domain === 'zooboardElements') {
        const { id: elemID, isDeleted } = msg.data
        if (isDeleted) {
          elementsByID.delete(elemID)
        } else {
          msgIDToElemID.set(msgID, elemID)
          elementsByID.set(elemID, msg.data)
        }
        mainWindow.webContents.send('readElements', [msg.data])
      }
    })

    // Subscribe to deleted elements and inform renderer
    peer.db.onRecordDeletedOrErased((msgID) => {
      const elemID = msgIDToElemID.get(msgID)
      if (!elemID) return
      msgIDToElemID.delete(msgID)
      // Is there some other msgID that supports this elemID? If so, bail out
      for (const [, remainingElemID] of msgIDToElemID) {
        if (remainingElemID === elemID) {
          return
        }
      }
      // If not, delete the element
      elementsByID.delete(elemID)
      mainWindow.webContents.send('readElements', [
        { id: elemID, isDeleted: true },
      ])
    })

    // Finally safe to kickstart replication and garbage collection
    setTimeout(() => {
      peer.conductor.start(
        globalAccountID,
        [
          ['profile@dict', 'zooboardElements@newest-100', 'hubs@set'],
          ['profile@dict', 'zooboardElements@newest-100'],
        ],
        64_000,
        (err) => {
          if (err) console.error('Starting conductor failed:', err)
        }
      )
    }, 32)
  }

  let hasSubscribedToConnections = false
  async function subscribeToConnections() {
    if (hasSubscribedToConnections) return
    hasSubscribedToConnections = true

    for await (const connections of awaitable(peer.net.peers())) {
      mainWindow.webContents.send('connections', connections)
    }
  }

  async function handlePZPUri(ev, uri) {
    if (!globalAccountID) {
      setTimeout(handlePZPUri, 100, null, uri)
      return
    }
    if (uri.startsWith("http:") || uri.startsWith("https://")) {
      uri = decodeURIComponent(uri.split('/invite#')[1])
    }
    if (!uri.startsWith('pzp://')) return console.log('Not a pzp invite URI', uri)
    const commands = peer.invite.parse(uri)
    for (const command of commands) {
      console.log('Executing command', JSON.stringify(command))
      switch (command.type) {
        case 'join': {
          try {
            await p(peer.hubClient.addHub)(command.multiaddr)
          } catch (err) {
            console.error('Failed to properly join hub', err)
          }
          break
        }
        case 'follow': {
          await p(peer.set.add)('follows', command.id)
          break
        }
        case 'promise.follow': {
          const [issuerType, issuerPubkey] = command.issuer
          if (issuerType !== 'pubkey') {
            throw new Error(`Dont know how to claim a ${issuerType} promise`)
          }
          // eslint-disable-next-line no-loop-func
          peer.addListener('rpc:connect', function onConnect(rpc) {
            if (rpc.shse.pubkey === issuerPubkey) {
              peer.removeListener('rpc:connect', onConnect)
              rpc.promise.follow(command.token, globalAccountID, (err) => {
                if (err) return console.error('Failed to use follow promise', err)
              })
            }
          })
          break
        }
        default:
          console.log('Unknown command type', command.type)
      }
    }
  }

  if (process.defaultApp) {
    if (process.argv.length >= 2) {
      app.setAsDefaultProtocolClient('pzp', process.execPath, [
        Path.resolve(process.argv[1]),
      ])
    }
  } else {
    app.setAsDefaultProtocolClient('pzp')
  }

  app.whenReady().then(() => {
    ipcMain.handle('loadAccount', loadAccount)
    ipcMain.handle('setProfileName', setProfileName)
    ipcMain.handle('createInvite', createInvite)
    ipcMain.handle('copyToClipboard', copyToClipboard)
    ipcMain.handle('writeElements', writeElements)
    ipcMain.handle('consumeInvite', handlePZPUri)
    ipcMain.handle('subscribeToReadElements', subscribeToReadElements)
    ipcMain.handle('subscribeToConnections', subscribeToConnections)
    createWindow()
    if (process.argv.length > 1) {
      handlePZPUri(null, process.argv[process.argv.length - 1])
    }

    app.on('activate', function () {
      if (BrowserWindow.getAllWindows().length === 0) createWindow()
    })
    app.on('window-all-closed', function () {
      if (process.platform !== 'darwin') app.quit()
    })
  })
}).catch(err => console.error("Couldn't create peer:", err))