package html

import (
	"fmt"
	"strings"

	"github.com/jedib0t/go-pretty/v6/table"
	"github.com/nmoniz/any2anexoj/internal"
	"github.com/nmoniz/any2anexoj/internal/writing/internal/tabledef"
)

// htmlCSSClass is the CSS class list put on the rendered report table.
const htmlCSSClass = "table table-striped table-hover table-bordered"

// widthIndex is the weight of the auto-index (row number) column; the other
// column weights come from tabledef's width budgets.
const widthIndex = 6

// htmlColumnWeights lists one weight per rendered column, starting with the
// auto-index column, mirroring the column order of tabledef.Build so the
// HTML table keeps columns in the same strict proportion to each other as
// the terminal layout.
var htmlColumnWeights = []int{
	widthIndex,
	tabledef.WidthCountry, tabledef.WidthOther, tabledef.WidthOther, tabledef.WidthOther, tabledef.WidthOther, tabledef.WidthEuros,
	tabledef.WidthOther, tabledef.WidthOther, tabledef.WidthOther, tabledef.WidthEuros,
	tabledef.WidthEuros, tabledef.WidthEuros, tabledef.WidthCountry,
}

// renderTableFragment renders aw as the Bootstrap-styled HTML <table>
// fragment embedded in the document. The table gets a fixed layout with
// strictly proportional column widths, so the browser — not this package —
// decides when a header or cell wraps: on wide screens everything fits on
// one line, on narrow ones it wraps automatically.
func (hw *Writer) renderTableFragment(aw *internal.AggregatorWriter) string {
	t := tabledef.Build(hw.translator, aw)
	t.Style().HTML = table.HTMLOptions{
		CSSClass:    htmlCSSClass,
		EscapeText:  true,
		Newline:     "<br/>",
		EmptyColumn: "&nbsp;",
	}
	html := t.RenderHTML()

	// go-pretty cannot emit table-level attributes or a <colgroup>, so splice
	// them into its output: the fixed layout makes the colgroup's relative
	// widths authoritative instead of content-driven column sizing.
	openTag := `<table class="` + htmlCSSClass + `">`
	fixedTag := `<table class="` + htmlCSSClass + `" style="table-layout: fixed">` + "\n" + colgroupHTML()
	return strings.Replace(html, openTag, fixedTag, 1)
}

// colgroupHTML returns a <colgroup> with one <col> per rendered column, each
// sized strictly in proportion to its weight. With the fixed table layout
// applied in renderTableFragment these widths are authoritative: wide
// viewports fit headers on a single line, narrow ones wrap automatically.
func colgroupHTML() string {
	var total int
	for _, w := range htmlColumnWeights {
		total += w
	}
	var sb strings.Builder
	sb.WriteString("<colgroup>")
	for _, w := range htmlColumnWeights {
		fmt.Fprintf(&sb, `<col style="width: %.2f%%">`, float64(w)/float64(total)*100)
	}
	sb.WriteString("</colgroup>")
	return sb.String()
}