<template>
    <div>
        <div class="content-section introduction">
            <div class="feature-intro">
                <h1>Polar Area Chart</h1>
                <p>Polar area charts are similar to pie charts, but each segment has the same angle - the radius of the segment differs depending on the value.</p>
            </div>
            <AppDemoActions />
        </div>

        <div class="content-section implementation">
            <div class="card flex justify-content-center">
                <Chart type="polarArea" :data="chartData" :options="chartOptions" style="width: 40%" />
            </div>
        </div>

        <PolarAreaChartDoc />
    </div>
</template>

<script>
import EventBus from '@/layouts/AppEventBus';
import PolarAreaChartDoc from './PolarAreaChartDoc';

export default {
    themeChangeListener: null,
    data() {
        return {
            chartData: {
                datasets: [
                    {
                        data: [11, 16, 7, 3, 14],
                        backgroundColor: ['#42A5F5', '#66BB6A', '#FFA726', '#26C6DA', '#7E57C2'],
                        label: 'My dataset'
                    }
                ],
                labels: ['Red', 'Green', 'Yellow', 'Grey', 'Blue']
            },
            chartOptions: this.isDarkTheme() ? this.getDarkTheme() : this.getLightTheme()
        };
    },
    mounted() {
        this.themeChangeListener = (event) => {
            if (event.dark) this.chartOptions = this.getDarkTheme();
            else this.chartOptions = this.getLightTheme();
        };

        EventBus.on('theme-change', this.themeChangeListener);
    },
    beforeUnmount() {
        EventBus.off('change-theme', this.themeChangeListener);
    },
    methods: {
        isDarkTheme() {
            return this.$appState.darkTheme === true;
        },
        getLightTheme() {
            return {
                plugins: {
                    legend: {
                        labels: {
                            color: '#495057'
                        }
                    }
                },
                scales: {
                    r: {
                        grid: {
                            color: '#ebedef'
                        }
                    }
                }
            };
        },
        getDarkTheme() {
            return {
                plugins: {
                    legend: {
                        labels: {
                            color: '#ebedef'
                        }
                    }
                },
                scales: {
                    r: {
                        grid: {
                            color: 'rgba(255,255,255,0.2)'
                        }
                    }
                }
            };
        }
    },
    components: {
        PolarAreaChartDoc: PolarAreaChartDoc
    }
};
</script>
