git ssb

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const Flume = require('flumedb')
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const Reduce = require('flumeview-reduce')
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const FlumeLog = require('flumelog-memory')
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function ledger (state, emitter) {
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  state.accounts = {}
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  state.entries = []
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  const db = Flume(FlumeLog())
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    .use('entries', Reduce(1, entriesReducer, null, null, state.entries))
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    .use('accounts', Reduce(1, accountReducer, null, null, state.accounts))
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    .use('balances', Reduce(1, accountBalanceReducer, null, null, state.accounts))
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  state.db = db
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  function onLoad () {
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    emitter.on('accounts', onEvent)
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    emitter.on('entries', onEvent)
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  }
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  function onEvent (data) {
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    db.append(data, (err, seq) => {
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      if (err) throw err
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      emitter.emit(state.events.RENDER)
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    })
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  }
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  emitter.on('DOMContentLoaded', onLoad)
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}
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function accountBalanceReducer (acc, item) {
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  if (item.type !== 'entries') return acc
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  const {msg} = item
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  acc[msg.debit].debit += msg.amount
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  acc[msg.credit].credit += msg.amount
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  return acc
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}
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function entriesReducer (acc, item) {
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  if (item.type !== 'entries') return acc
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  acc.push(item)
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  return acc
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}
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function accountReducer (acc, item) { // TODO account for account creation of existing account
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  if (item.type !== 'accounts') return acc
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  const { msg } = item
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  if (!acc[msg.name]) {
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    acc[msg.name] = msg
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    return acc
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  }
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  Object.assign(acc[msg.name], msg)
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  return acc
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}
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module.exports = ledger
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