package net

import (
	"strconv"

	"git.smesh.lol/torly/pkg/nostr"
)

func eventMsg(sub string, data []byte) []byte {
	buf := make([]byte, 0, len(data)+len(sub)+16)
	buf = append(buf, `["EVENT",`...)
	buf = nostr.AppendJSONString(buf, sub)
	buf = append(buf, ',')
	buf = append(buf, data...)
	return append(buf, ']')
}

func okMsg(id string, good bool, msg string) []byte {
	buf := make([]byte, 0, len(id)+len(msg)+16)
	buf = append(buf, `["OK","`...)
	buf = append(buf, id...)
	buf = append(buf, `",`...)
	if good {
		buf = append(buf, "true"...)
	} else {
		buf = append(buf, "false"...)
	}
	buf = append(buf, ',')
	buf = nostr.AppendJSONString(buf, msg)
	return append(buf, ']')
}

func eoseMsg(sub string) []byte {
	buf := make([]byte, 0, len(sub)+12)
	buf = append(buf, `["EOSE",`...)
	buf = nostr.AppendJSONString(buf, sub)
	return append(buf, ']')
}

func noticeMsg(msg string) []byte {
	buf := make([]byte, 0, len(msg)+12)
	buf = append(buf, `["NOTICE",`...)
	buf = nostr.AppendJSONString(buf, msg)
	return append(buf, ']')
}

func closedMsg(sub, msg string) []byte {
	buf := make([]byte, 0, len(sub)+len(msg)+14)
	buf = append(buf, `["CLOSED",`...)
	buf = nostr.AppendJSONString(buf, sub)
	buf = append(buf, ',')
	buf = nostr.AppendJSONString(buf, msg)
	return append(buf, ']')
}

func authMsg(challenge string) []byte {
	buf := make([]byte, 0, len(challenge)+12)
	buf = append(buf, `["AUTH",`...)
	buf = nostr.AppendJSONString(buf, challenge)
	return append(buf, ']')
}

func countMsg(sub string, n int, approximate bool) []byte {
	buf := make([]byte, 0, len(sub)+48)
	buf = append(buf, `["COUNT",`...)
	buf = nostr.AppendJSONString(buf, sub)
	buf = append(buf, `,{"count":`...)
	buf = strconv.AppendInt(buf, int64(n), 10)
	buf = append(buf, `,"approximate":`...)
	if approximate {
		buf = append(buf, "true"...)
	} else {
		buf = append(buf, "false"...)
	}
	return append(buf, `}]`...)
}

func filterMatches(ev *nostr.Event, f *nostr.Filter) bool {
	if !f.Matches(ev) {
		return false
	}
	if f.Search == "" {
		return true
	}
	want := tokenize(f.Search)
	if len(want) == 0 {
		return true
	}
	have := make(map[string]struct{})
	for w := range tokenize(ev.Content) {
		have[w] = struct{}{}
	}
	for w := range want {
		if _, ok := have[w]; !ok {
			return false
		}
	}
	return true
}

func tokenize(s string) map[string]struct{} {
	out := make(map[string]struct{})
	var buf []byte
	flush := func() {
		if len(buf) >= 3 {
			out[string(buf)] = struct{}{}
		}
		buf = buf[:0]
	}
	for i := 0; i < len(s); i++ {
		c := s[i]
		switch {
		case c >= 'a' && c <= 'z', c >= '0' && c <= '9':
			buf = append(buf, c)
		case c >= 'A' && c <= 'Z':
			buf = append(buf, c+32)
		default:
			flush()
		}
	}
	flush()
	return out
}