package tui

import (
	"strings"

	"github.com/lerko/nib/internal/link"
)

type linkPickerModel struct {
	links  []string
	cursor int
}

func newLinkPicker(body string) linkPickerModel {
	return linkPickerModel{
		links: link.ExtractLinks(body),
	}
}

func (lp linkPickerModel) selected() string {
	if len(lp.links) == 0 || lp.cursor >= len(lp.links) {
		return ""
	}
	return lp.links[lp.cursor]
}

func (lp linkPickerModel) update(key string) linkPickerModel {
	switch key {
	case "up", "k":
		if lp.cursor > 0 {
			lp.cursor--
		}
	case "down", "j":
		if lp.cursor < len(lp.links)-1 {
			lp.cursor++
		}
	}
	return lp
}

func (lp linkPickerModel) view(width int) string {
	var b strings.Builder
	b.WriteString(titleStyle.Render("follow link") + "\n\n")

	if len(lp.links) == 0 {
		b.WriteString(hintDescStyle.Render("  no [[links]] in this entry"))
		b.WriteString("\n\n")
		b.WriteString(helpStyle.Render("esc:back"))
		return b.String()
	}

	for i, lt := range lp.links {
		label := "[[" + lt + "]]"
		if i == lp.cursor {
			b.WriteString(selectedItemStyle.Render(" " + label))
		} else {
			b.WriteString(listItemStyle.Render(label))
		}
		b.WriteString("\n")
	}

	b.WriteString("\n")
	b.WriteString(helpStyle.Render("enter:follow  esc:back"))
	return b.String()
}