package ansi

import (
	"bytes"
	"errors"
	"io"
	"strconv"
	"strings"

	"charm.land/lipgloss/v2"
	"github.com/charmbracelet/x/ansi"
)

// An ItemElement is used to render items inside a list.
type ItemElement struct {
	IsOrdered   bool
	Enumeration uint
}

// Render renders an ItemElement.
func (e *ItemElement) Render(w io.Writer, ctx RenderContext) error {
	var el *BaseElement
	if e.IsOrdered {
		el = &BaseElement{
			Style:  ctx.options.Styles.Enumeration,
			Prefix: strconv.FormatInt(int64(e.Enumeration), 10), //nolint:gosec
		}
	} else {
		el = &BaseElement{
			Style: ctx.options.Styles.Item,
		}
	}

	return el.Render(w, ctx)
}

// A ListItemElement renders a list item as a block: its marker leads the
// first row and every later row hangs under the text after it, so wrapped
// lines, paragraphs, code and nested lists stay inside the item.
type ListItemElement struct {
	Marker ElementRenderer
}

func (e *ListItemElement) marker(ctx RenderContext) string {
	var marker bytes.Buffer
	_ = e.Marker.Render(&marker, ctx)
	return marker.String()
}

// Render opens the item's block, indented by the marker's width.
func (e *ListItemElement) Render(_ io.Writer, ctx RenderContext) error {
	width := uint(ansi.StringWidth(e.marker(ctx))) //nolint:gosec
	bs := ctx.blockStack
	bs.Push(BlockElement{
		Block: &bytes.Buffer{},
		Style: cascadeStyle(bs.Current().Style, StyleBlock{Indent: &width}, false),
	})
	return nil
}

// Finish writes the item: the marker leads its first row and pads the rest.
func (e *ListItemElement) Finish(w io.Writer, ctx RenderContext) error {
	bs := ctx.blockStack
	marker := e.marker(ctx)
	lead, pad := marker, strings.Repeat(" ", ansi.StringWidth(marker))
	iw := NewIndentWriter(w, 1, func(w io.Writer) {
		_, _ = io.WriteString(w, lead)
		lead = pad
	})
	body := lipgloss.Wrap(bs.Current().Block.String(), int(bs.Width(ctx)), " ,.;-+|")
	_, err := io.WriteString(iw, strings.TrimRight(body, "\n"))
	bs.Current().Block.Reset()
	bs.Pop()
	return errors.Join(err, iw.Close())
}