package alias

import (
	"strings"

	"github.com/go-telegram/bot/models"
)

// replyShape describes what /alias was handed, for the debug log.
//
// Enable with LOG_LEVEL=debug; silent otherwise. It exists because the failures
// worth debugging here are all about what Telegram *did not* deliver: a reply
// stripped of its content (another bot's message), a caption where text was
// expected, or a kind that falls through capture's switch. Those are invisible
// from the user-facing refusal, which only says the message was unsupported.
//
// Deliberately reports shape, never content. Lengths and field names are
// enough to explain a capture failure, and message text in a log line would
// mean every aliased message ending up in stdout and whatever ships it.
func replyShape(replied *models.Message, entry Alias, ok bool) []any {
	if replied == nil {
		// The case that motivated this: Telegram can deliver /alias with no
		// reply attached at all, which is indistinguishable from the caller
		// forgetting to reply.
		return []any{"reply", "absent"}
	}

	attrs := []any{
		"reply", "present",
		"reply_id", replied.ID,
		"fields", strings.Join(populatedFields(replied), ","),
		"text_len", len(replied.Text),
		"caption_len", len(replied.Caption),
		"entities", len(replied.Entities) + len(replied.CaptionEntities),
		"captured", ok,
	}
	if ok {
		attrs = append(attrs, "kind", entry.Kind)
	}
	if replied.From != nil {
		attrs = append(attrs, "from_id", replied.From.ID, "from_bot", replied.From.IsBot)
	} else {
		// No sender at all — an anonymous channel post or a stripped reply.
		attrs = append(attrs, "from", "absent")
	}
	if replied.SenderChat != nil {
		attrs = append(attrs, "sender_chat", replied.SenderChat.ID)
	}
	return attrs
}

// populatedFields names the content fields the replied message actually has.
//
// Covers more than capture handles on purpose: the point is to show what
// arrived, including kinds this module refuses, so "unsupported" can be told
// apart from "empty".
func populatedFields(m *models.Message) []string {
	var out []string
	add := func(present bool, name string) {
		if present {
			out = append(out, name)
		}
	}
	add(m.Text != "", "text")
	add(m.Caption != "", "caption")
	add(m.Sticker != nil, "sticker")
	add(len(m.Photo) > 0, "photo")
	add(m.Animation != nil, "animation")
	add(m.Video != nil, "video")
	add(m.VideoNote != nil, "video_note")
	add(m.Audio != nil, "audio")
	add(m.Voice != nil, "voice")
	add(m.Document != nil, "document")
	add(m.Location != nil, "location")
	add(m.Contact != nil, "contact")
	add(m.Poll != nil, "poll")
	add(m.Dice != nil, "dice")
	add(m.Venue != nil, "venue")
	add(m.Game != nil, "game")
	add(m.ViaBot != nil, "via_bot")
	add(m.ForwardOrigin != nil, "forward_origin")
	if len(out) == 0 {
		// The signature of a reply Telegram delivered but emptied.
		out = append(out, "none")
	}
	return out
}