package tui

import "github.com/charmbracelet/bubbles/table"

const (
	sidebarWidth = 18
	footerHeight = 1
	titleHeight  = 2
	boxChromeV   = 2
	boxChromeH   = 4
)

// flexColumns grows the columns at flexIdx to fill totalW, distributing extra
// space proportionally to each flex column's existing width. Bubble-tea's
// table widget reserves padding around every cell, accounted for via colPadding.
func flexColumns(totalW int, cols []table.Column, flexIdx []int) []table.Column {
	out := make([]table.Column, len(cols))
	copy(out, cols)
	if totalW <= 0 || len(flexIdx) == 0 {
		return out
	}
	const colPadding = 2
	used := 0
	for _, c := range out {
		used += c.Width + colPadding
	}
	extra := totalW - used
	if extra <= 0 {
		return out
	}
	totalFlex := 0
	for _, i := range flexIdx {
		if i < 0 || i >= len(out) {
			return out
		}
		totalFlex += out[i].Width
	}
	if totalFlex == 0 {
		return out
	}
	distributed := 0
	for j, i := range flexIdx {
		var add int
		if j == len(flexIdx)-1 {
			add = extra - distributed
		} else {
			add = extra * out[i].Width / totalFlex
		}
		out[i].Width += add
		distributed += add
	}
	return out
}

type layoutDims struct {
	termW, termH   int
	contentW       int
	contentH       int
	sidebarH       int
}

func computeLayout(termW, termH int) layoutDims {
	if termW < 60 {
		termW = 60
	}
	if termH < 18 {
		termH = 18
	}
	contentW := termW - sidebarWidth - boxChromeH - 1
	if contentW < 40 {
		contentW = 40
	}
	contentH := termH - titleHeight - footerHeight - boxChromeV
	if contentH < 10 {
		contentH = 10
	}
	return layoutDims{
		termW:    termW,
		termH:    termH,
		contentW: contentW,
		contentH: contentH,
		sidebarH: contentH,
	}
}