atst/js/components/charts/budget_chart.js
2018-09-11 11:25:52 -04:00

136 lines
4.0 KiB
JavaScript

import { format } from 'date-fns'
import { abbreviateDollars, formatDollars } from '../../lib/dollars'
const TOP_OFFSET = 20
const BOTTOM_OFFSET = 60
const CHART_HEIGHT = 360
export default {
name: 'budget-chart',
props: {
currentMonth: String,
months: Object,
budget: String
},
data: function () {
const heightScale = this.budget / (CHART_HEIGHT - TOP_OFFSET - BOTTOM_OFFSET)
return {
numMonths: 10,
focusedMonthPosition: 4,
height: CHART_HEIGHT,
heightScale,
budgetHeight: CHART_HEIGHT - BOTTOM_OFFSET - (this.budget / heightScale),
baseHeight: CHART_HEIGHT - BOTTOM_OFFSET,
width: 0,
displayedMonths: [],
spendPath: '',
projectedPath: '',
displayBudget: formatDollars(parseFloat(this.budget))
}
},
mounted: function () {
this._setDisplayedMonths()
this._setMetrics()
addEventListener('resize', this._setMetrics)
},
methods: {
_setMetrics: function () {
this.width = this.$refs.panel.clientWidth
this.spendPath = ''
this.projectedPath = ''
let lastSpend = 0
let lastSpendPoint = ''
for (let i = 0; i < this.numMonths; i++) {
const { metrics, budget } = this.displayedMonths[i]
const blockWidth = (this.width / this.numMonths)
const blockX = blockWidth * i
const spend = budget
? budget.spend || lastSpend
: 0
const cumulative = budget
? budget.cumulative || budget.projected
: 0
const barHeight = spend / this.heightScale
lastSpend = spend
const cumulativeY = this.height - (cumulative / this.heightScale) - BOTTOM_OFFSET
const cumulativeX = blockX + blockWidth/2
const cumulativePoint = `${cumulativeX} ${cumulativeY}`
this.displayedMonths[i].metrics = Object.assign(metrics, {
blockWidth,
blockX,
barHeight,
barWidth: 30,
barX: blockX + (blockWidth/2 - 15),
barY: this.height - barHeight - BOTTOM_OFFSET,
cumulativeR: 2.5,
cumulativeY,
cumulativeX
})
if (budget && budget.spend) {
this.spendPath += this.spendPath === '' ? 'M' : ' L'
this.spendPath += cumulativePoint
lastSpendPoint = cumulativePoint
}
if (budget && budget.projected) {
this.projectedPath += this.projectedPath === '' ? `M${lastSpendPoint} L` : ' L'
this.projectedPath += cumulativePoint
}
}
},
_setDisplayedMonths: function () {
const [month, year] = this.currentMonth.split('/')
const monthsRange = []
const monthsBack = this.focusedMonthPosition
const monthsForward = this.numMonths - this.focusedMonthPosition - 1
const start = new Date(year, month - 1 - monthsBack)
let previousAmount = 0
for (let i = 0; i < this.numMonths; i++) {
const date = new Date(start.getFullYear(), start.getMonth() + i)
const index = format(date, 'MM/YYYY')
const budget = this.months[index] || null
const spendAmount = budget ? budget.spend || previousAmount : 0
const cumulativeAmount = budget ? budget.cumulative || budget.projected : 0
previousAmount = spendAmount
monthsRange.push({
budget,
spendAmount: formatDollars(spendAmount),
abbreviatedSpend: abbreviateDollars(spendAmount),
cumulativeAmount: formatDollars(cumulativeAmount),
abbreviatedCumulative: abbreviateDollars(cumulativeAmount),
date: {
monthIndex: format(date, 'M'),
month: format(date, 'MMM'),
year: format(date,'YYYY')
},
isHighlighted: this.currentMonth === index,
metrics: {
blockWidth: 0,
blockX: 0,
barHeight: 0,
barWidth: 0,
barX: 0,
barY: 0,
cumulativeY: 0,
cumulativeX: 0,
cumulativeR: 0
}
})
}
this.displayedMonths = monthsRange
}
}
}