package kpoll

import (
	"fmt"
	"strings"

	"gotest.tools/v3/poll"
)

// JoinResults combines one or more polling results into a single
// [gotest.tools/v3/poll.Result].
//
// At least one poll.Result must be provided. If a single poll.Result is passed
// in, it is returned directly.
//
// If any results contain an error, it is immediately returned. Otherwise, all
// unfinished results have their messages combined into a single
// [gotest.tools/v3/poll.Continue] call. If all results indicate they are done,
// [gotest.tools/v3/poll.Success] is returned.
//
// TODO(aw18576): Consider generalizing this
func JoinResults(results ...poll.Result) poll.Result {
	if len(results) == 0 {
		return poll.Error(fmt.Errorf("can't join 0 results, need at least one"))
	}
	if len(results) == 1 {
		return results[0] //nolint:gosec // I know the array has a length of 1
	}

	var msgs []string
	for _, r := range results {
		if r.Error() != nil {
			return r
		}
		if !r.Done() {
			msgs = append(msgs, r.Message())
		}
	}

	if len(msgs) > 0 {
		return poll.Continue("waiting on %d checks (%d/%d complete):\n%s",
			len(msgs), len(results)-len(msgs), len(results), strings.Join(msgs, "\n\n"))
	}
	return poll.Success()
}