2023-11-20 00:38:52 +01:00

136 lines
4.0 KiB
Vue

<template>
<!-- eslint-disable -->
<div class="my-3">
<pre>
_ _
_ __ ___ __ _ _ __| | _____| |_
| '_ ` _ \ / _` | '__| |/ / _ \ __|
| | | | | | (_| | | | ( __/ |_
|_| |_| |_|\__,_|_| |_|\_\___|\__|</pre>
</div>
<div class="font-mono">{{ market.Description }}</div>
<!-- eslint-enable -->
<button type="button" :class="yesClass" class="label success font-mono mx-1 my-3"
@click.prevent="toggleYes">YES</button>
<button type="button" :class="noClass" class="label error font-mono mx-1 my-3" @click.prevent="toggleNo">NO</button>
<form v-show="showForm" @submit.prevent="submitForm">
<label for="stake">how much?</label>
<input name="stake" v-model="stake" type="number" min="0" placeholder="🗲 sats" />
<label for="certainty">how sure?</label>
<input name="certainty" v-model="certainty" type="number" min="0" max="1" step="0.001"
placeholder="fraction like 0.5" />
<label>you receive:</label>
<label>{{ format(shares) }} {{ selected }} shares @ 🗲{{ format(price) }}</label>
<label>you pay:</label>
<label>🗲{{ format(cost) }}</label>
<label>if you win:</label>
<label>+🗲{{ format(profit) }}</label>
<button class="col-span-2" type="submit">submit order</button>
</form>
</template>
<script setup>
import { ref, computed } from 'vue'
import { useRoute, useRouter } from 'vue-router'
const router = useRouter()
const route = useRoute()
const marketId = route.params.id
const selected = ref(null)
const showForm = computed(() => selected.value !== null)
const yesClass = computed(() => selected.value === 'YES' ? ['active'] : [])
const noClass = computed(() => selected.value === 'NO' ? ['active'] : [])
// how much wants the user bet?
const stake = ref(null)
// how sure is the user he will win?
const certainty = ref(null)
// price per share: more risk, lower price, higher reward
const price = computed(() => certainty.value * 100)
// how many (full) shares can be bought?
const shares = computed(() => {
const val = price.value > 0 ? stake.value / price.value : null
// only full shares can be bought
return Math.round(val)
})
// how much does this order cost?
const cost = computed(() => {
return shares.value * price.value
})
// how high is the potential reward?
const profit = computed(() => {
// shares expire at 10 or 0 sats
const val = (100 * shares.value) - cost.value
return isNaN(val) ? 0 : val
})
const format = (x, i = 3) => x === null ? null : x >= 1 ? Math.round(x) : x.toFixed(i)
const market = ref(null)
const url = '/api/market/' + marketId
await fetch(url)
.then(r => r.json())
.then(body => {
market.value = body
})
.catch(console.error)
// Currently, we only support binary markets.
// (only events which can be answered with YES and NO)
const yesShareId = computed(() => {
return market?.value.Shares.find(s => s.Description === 'YES').Id
})
const noShareId = computed(() => {
return market?.value.Shares.find(s => s.Description === 'NO').Id
})
const shareId = computed(() => {
return selected.value === 'YES' ? yesShareId.value : noShareId.value
})
const toggleYes = () => {
selected.value = selected.value === 'YES' ? null : 'YES'
}
const toggleNo = () => {
selected.value = selected.value === 'NO' ? null : 'NO'
}
const submitForm = async () => {
// TODO validate form
const url = window.origin + '/api/order'
const body = JSON.stringify({
sid: shareId.value,
quantity: shares.value,
price: price.value,
// TODO support selling
side: 'BUY'
})
const res = await fetch(url, { method: 'POST', headers: { 'Content-type': 'application/json' }, body })
const resBody = await res.json()
const invoiceId = resBody.id
router.push('/invoice/' + invoiceId)
}
</script>
<style scoped>
.success.active {
background-color: #35df8d;
color: white;
}
.error.active {
background-color: #ff7386;
color: white;
}
form {
margin: 0 auto;
display: grid;
grid-template-columns: auto auto;
}
form>* {
margin: 0.5em 1em;
}
</style>