package main

import (
	"context"
	"io"
	"math/rand"
	"net/http"

	"github.com/a-h/templ"
	"github.com/go-echarts/go-echarts/v2/charts"
	"github.com/go-echarts/go-echarts/v2/opts"
)

func generateBarItems() []opts.BarData {
	items := make([]opts.BarData, 0)
	for range 7 {
		items = append(items, opts.BarData{Value: rand.Intn(300)})
	}
	return items
}

func createBarChart() *charts.Bar {
	bar := charts.NewBar()
	bar.SetGlobalOptions(charts.WithTitleOpts(opts.Title{
		Title:    "Bar chart",
		Subtitle: "That works well with templ",
	}))
	bar.SetXAxis([]string{"Mon", "Tue", "Wed", "Thu", "Fri", "Sat", "Sun"}).
		AddSeries("Category A", generateBarItems()).
		AddSeries("Category B", generateBarItems())
	return bar
}

// The charts all have a `Render(w io.Writer) error` method on them.
// That method is very similar to templ's Render method.
type Renderable interface {
	Render(w io.Writer) error
}

// So lets adapt it.
func ConvertChartToTemplComponent(chart Renderable) templ.Component {
	return templ.ComponentFunc(func(ctx context.Context, w io.Writer) error {
		return chart.Render(w)
	})
}

func main() {
	http.HandleFunc("/", func(w http.ResponseWriter, r *http.Request) {
		chart := createBarChart()
		h := templ.Handler(Home(chart))
		h.ServeHTTP(w, r)
	})
	http.ListenAndServe("localhost:3000", nil)
}
