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-offset')
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const { pull, drain } = require('pull-stream')
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const codec = require('flumecodec')
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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('.test.db', { codec: codec.json }))
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    .use('entries', Reduce(1, entriesReducer, null, null, []))
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    .use('accounts', Reduce(1, accountReducer, null, null, {}))
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  const onDone = () => console.log('DONE')
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  pull(db.accounts.stream(), drain(acctState => {
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    state.accounts = acctState
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    emitter.emit.RENDER
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  }, onDone))
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  pull(db.entries.stream(), drain(entryState => {
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    state.entries = entryState
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    emitter.emit.RENDER
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  }, onDone))
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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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  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 === 'entries') {
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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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    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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    Object.assign(state.accounts[msg.name], msg)
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    return acc
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  }
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}
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module.exports = ledger
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