<template>
  <div>
    <div class="wrap">
      <h1>Activation rate by market, 2023 to 2025</h1>
      <p class="lead">
        Forty-two panels, no axes, one shared scale stated once. Every panel
        labels its own latest value, so the grid stays readable at 42 markets
        where a 42-series line chart is a hairball and a 42-row table is
        homework.
      </p>
      <p class="key">
        <span class="up">Top 5</span> vs <span class="down">Bottom 5</span>
        <span class="rest"
          >by latest rate, all panels on a shared 0-10% scale</span
        >
      </p>

      <div class="chart-wrap">
        <div id="chart">
          <apexchart
            type="line"
            height="700"
            :options="chartOptions"
            :series="series"
          ></apexchart>
        </div>
      </div>

      <div class="note">
        Dropping the axes is the user's own options, not a trellis mode: turn
        the labels, ticks, borders and gridlines off and every panel loses the
        same space, so the panels stay pixel-aligned. The conditional tint comes
        from
        <code>trellis.panel</code>, which is merged last and can therefore
        override anything, here a <code>chart.background</code> and a stroke
        colour per panel. Every cell also carries its facet key as
        <code>data-key</code>, so plain CSS can style the panel chrome (the
        header, the border) the same way. Hovering gives a one-line tooltip
        rather than a card: panels this short get <code>tooltip.compact</code>
        automatically (set it yourself, either way, and the trellis leaves the
        decision alone). Trellis is a premium feature; without a license it
        renders with a trial watermark.
      </div>
    </div>
  </div>
</template>

<script>
import VueApexCharts from 'vue-apexcharts'

import 'apexcharts/features/trellis'

// Forty-two markets, three years of monthly activation rate, no axes at all.
// At this size an axis costs more than it pays: the shared scale is stated
// once in the caption, each panel labels its own latest value, and the ink
// left over is the trend. The five best and five weakest latest rates are
// tinted so the extremes are findable without reading 42 numbers.
//
// Deterministic series so the e2e snapshot is stable.
function mulberry32(seed) {
  return function () {
    seed |= 0
    seed = (seed + 0x6d2b79f5) | 0
    var t = Math.imul(seed ^ (seed >>> 15), 1 | seed)
    t = (t + Math.imul(t ^ (t >>> 7), 61 | t)) ^ t
    return ((t ^ (t >>> 14)) >>> 0) / 4294967296
  }
}

var MARKETS = [
  'Amsterdam',
  'Antwerp',
  'Athens',
  'Auckland',
  'Austin',
  'Bergen',
  'Bilbao',
  'Bologna',
  'Bristol',
  'Calgary',
  'Cardiff',
  'Cork',
  'Dublin',
  'Dundee',
  'Edinburgh',
  'Galway',
  'Ghent',
  'Graz',
  'Helsinki',
  'Kingston',
  'Leeds',
  'Leiden',
  'Lisbon',
  'Lyon',
  'Malaga',
  'Malmo',
  'Nantes',
  'Oporto',
  'Oslo',
  'Ottawa',
  'Padua',
  'Perth',
  'Reykjavik',
  'Rotterdam',
  'Salerno',
  'Seville',
  'Tampere',
  'Turin',
  'Turku',
  'Utrecht',
  'Verona',
  'Zurich',
]

var MONTHS = 36
var START = new Date(2023, 0, 1).getTime()
var MONTH_MS = 30.44 * 24 * 3600 * 1000

// A trend plus a wobble, so the panels have shape rather than noise.
function activationSeries(seed, start, drift) {
  var rand = mulberry32(seed)
  var out = []
  var v = start
  for (var m = 0; m < MONTHS; m++) {
    v += drift + (rand() - 0.5) * 0.55
    // A mild seasonal lift in the second half of each year.
    var season = Math.sin(((m % 12) / 12) * Math.PI * 2) * 0.28
    out.push({
      x: Math.round(START + m * MONTH_MS),
      y: Math.max(1.2, Math.round((v + season) * 100) / 100),
    })
  }
  return out
}

var marketSeries = MARKETS.map(function (name, i) {
  var rand = mulberry32(1000 + i * 13)
  var start = 2.4 + rand() * 3.2
  var drift = (rand() - 0.42) * 0.11
  return {
    name: 'Activation rate',
    market: name,
    data: activationSeries(200 + i * 7, start, drift),
  }
})

// Rank on the LATEST value: the five best get the teal tint, the five
// weakest the amber one, everything else stays quiet grey.
var latest = {}
marketSeries.forEach(function (s) {
  latest[s.market] = s.data[s.data.length - 1].y
})
var ranked = MARKETS.slice().sort(function (a, b) {
  return latest[b] - latest[a]
})
var TOP = {}
var BOTTOM = {}
ranked.slice(0, 5).forEach(function (m) {
  TOP[m] = true
})
ranked.slice(-5).forEach(function (m) {
  BOTTOM[m] = true
})

export default {
  components: {
    apexchart: VueApexCharts,
  },
  data: function () {
    return {
      series: marketSeries,
      chartOptions: {
        chart: {
          id: 'marketTrellis',
          type: 'line',
          height: 700,
          animations: {
            enabled: false,
          },
        },
        trellis: {
          by: 'market',
          columns: 7,
          minPanelWidth: 130,
          panelHeight: 76,
          gap: 6,
          header: {
            style: {
              fontSize: '11px',
              fontWeight: 600,
            },
          },
          panel: function (key) {
            // The value label rides the last point, so which SIDE of it has room
            // depends on where that point sits in the shared 0-10 frame: below for a
            // high panel, above for a low one. `panel()` is merged last, so the
            // per-panel offset is a two-line override.
            var side = { dataLabels: { offsetY: latest[key] > 5 ? 15 : -8 } }
            if (TOP[key]) {
              return Object.assign(
                { colors: ['#0F766E'], chart: { background: '#EAF4F2' } },
                side,
              )
            }
            if (BOTTOM[key]) {
              return Object.assign(
                { colors: ['#B45309'], chart: { background: '#FBF1E3' } },
                side,
              )
            }
            return Object.assign({ colors: ['#94A3B8'] }, side)
          },
        },
        stroke: {
          width: 1.5,
          curve: 'straight',
        },
        markers: {
          size: 0,
          discrete: [
            {
              seriesIndex: 0,
              dataPointIndex: 35,
              size: 3,
              strokeWidth: 0,
            },
          ],
        },
        dataLabels: {
          enabled: true,
          offsetX: -10,
          offsetY: -8,
          background: {
            enabled: false,
          },
          style: {
            fontSize: '10px',
            fontWeight: 600,
            colors: ['#475569'],
          },
          formatter: function (val, opts) {
            var d = opts.w.config.series[opts.seriesIndex].data
            return opts.dataPointIndex === d.length - 1
              ? Number(val).toFixed(1)
              : ''
          },
        },
        yaxis: {
          labels: {
            show: false,
          },
        },
        xaxis: {
          type: 'datetime',
          labels: {
            show: false,
          },
          axisTicks: {
            show: false,
          },
          axisBorder: {
            show: false,
          },
          tooltip: {
            enabled: false,
          },
        },
        grid: {
          show: false,
          padding: {
            left: 4,
            right: 4,
          },
        },
        tooltip: {
          x: {
            format: 'MMM yyyy',
          },
        },
      },
    }
  },
}
</script>

<style>
body {
  font-family:
    -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  background: #fafbfc;
  color: #2c3e50;
  margin: 0;
  padding: 32px 16px;
}
.wrap {
  max-width: 1160px;
  margin: 0 auto;
}
h1 {
  font-size: 22px;
  margin: 0 0 8px;
}
.lead {
  color: #5b6b78;
  line-height: 1.5;
  margin: 0 0 14px;
}
.key {
  font-size: 14px;
  font-weight: 600;
  margin: 0 0 18px;
}
.key .up {
  color: #0f766e;
}
.key .down {
  color: #b45309;
}
.key .rest {
  color: #94a3b8;
  font-weight: 400;
}
.chart-wrap {
  background: #fff;
  border-radius: 8px;
  padding: 14px;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.04);
}
.note {
  background: #f0fdf4;
  border-left: 3px solid #15803d;
  padding: 12px 16px;
  font-size: 13px;
  color: #333;
  border-radius: 2px;
  line-height: 1.6;
  margin: 26px auto 0;
}
.note code {
  background: #dcfce7;
  padding: 1px 5px;
  border-radius: 3px;
}
</style>