package check

import (
	"context"
	"strings"
	"testing"
	"time"

	"git.novox.be/novox/mesh-sdk/go/delivery"
)

// What the gate reads of the checker (R4e, lead's interface with dev-r4e-gate): the verdict's heads are the gate's hash over
// `<owner/name lowercase>#<number>=<full head sha>`, a lone pull request is a group of one, and a move of a trunk marks
// mesh/check pending on every open pull request into it, every member's for a group, before any check starts.

func owedState(t testing.TB, r *rig, repo string, number int, head string) string {
	t.Helper()
	key, err := delivery.CheckerOwedKey(repo, number, head)
	if err != nil {
		t.Fatal(err)
	}
	raw, _, found, _ := r.owed.Get(context.Background(), key)
	if !found {
		return ""
	}
	o, err := delivery.DecodeCheckerOwed(raw)
	if err != nil {
		t.Fatal(err)
	}
	return o.State
}

func TestTheVerdictsHeadsAreTheGatesHashOverLowercaseHeads(t *testing.T) { // gate (b), (c)
	ctx := context.Background()
	r := newRig(t, passJudge())
	upper := strings.ToUpper(head1[:20]) + head1[20:]
	r.setTrunks(t, map[string]string{"Novox/Mesh-Delivery": trunkA, repoA: trunkA, repoSDK: trunkS})
	cand := candidateOf(t, "feat/x", pullOf("Novox/Mesh-Delivery", 7, upper))
	r.ch.Candidate(ctx, "feat%2Fx", cand)
	r.ch.Wait()
	want, _ := delivery.HeadsHash([]delivery.Head{{Repository: repoA, Number: 7, Head: head1}})
	if v := r.verdict(t, keyOf(t, "feat/x", cand)); v.Heads != want {
		t.Errorf("heads = %q, want the gate's hash of the lone pull request, a group of one, %q", v.Heads, want)
	}
}

func TestAGroupsVerdictHeadsCoverEveryMember(t *testing.T) { // gate (b): hq's member too, as the gate's ask covers it
	ctx := context.Background()
	r := newRig(t, passJudge())
	cand := candidateOf(t, "feat/x", pullOf(repoA, 7, head1), pullOf(repoSDK, 12, head2), pullOf(hqRepo, 3, head2))
	r.ch.Candidate(ctx, "feat%2Fx", cand)
	r.ch.Wait()
	want, _ := delivery.HeadsHash([]delivery.Head{{Repository: repoA, Number: 7, Head: head1}, {Repository: repoSDK, Number: 12, Head: head2},
		{Repository: hqRepo, Number: 3, Head: head2}})
	if v := r.verdict(t, keyOf(t, "feat/x", cand)); v.Heads != want {
		t.Errorf("heads = %q, want %q", v.Heads, want)
	}
}

func TestATrunkMoveMarksEveryOpenPullRequestIntoItPendingAtOnce(t *testing.T) { // gate (a), lead decision L4 (1302's checker part)
	ctx := context.Background()
	r := newRig(t, passJudge())
	r.ch.Candidate(ctx, "feat%2Fg", candidateOf(t, "feat/g", pullOf(repoA, 7, head1), pullOf(repoSDK, 12, head2)))
	r.ch.Candidate(ctx, "feat%2Fs", candidateOf(t, "feat/s", pullOf(repoSDK, 13, head1)))
	r.ch.Wait()
	for _, p := range []struct {
		repo string
		n    int
		head string
	}{{repoA, 7, head1}, {repoSDK, 12, head2}, {repoSDK, 13, head1}} {
		if s := owedState(t, r, p.repo, p.n, p.head); s != "success" {
			t.Fatalf("%s#%d is %q before the move", p.repo, p.n, s)
		}
	}
	// mesh-delivery's trunk moves; the re-judges it asks are held in their judge (in the stream, since R4g) meanwhile.
	release := make(chan struct{})
	r.ch.Judge = &judgeFunc{f: func(context.Context, *Case, int) (Outcome, error) { <-release; return Outcome{Verdict: passing()}, nil }}
	defer func() { close(release); r.ch.Wait() }()
	r.setTrunks(t, map[string]string{repoA: trunkA2, repoSDK: trunkS})
	r.ch.TrunkMoved(ctx)
	if s := owedState(t, r, repoA, 7, head1); s != "pending" {
		t.Errorf("mesh-delivery#7, into the moved trunk, is %q, want pending", s)
	}
	if s := owedState(t, r, repoSDK, 12, head2); s != "pending" {
		t.Errorf("mesh-sdk#12, a member of the same group, is %q, want pending", s)
	}
	if s := owedState(t, r, repoSDK, 13, head1); s != "success" {
		t.Errorf("mesh-sdk#13, alone into a trunk that did not move, is %q, want its success to stand", s)
	}
}

func TestACheckThatEndsAfterItsTrunkMovedOwesPendingNotItsVerdict(t *testing.T) { // gate (a): a pass on an old trunk is never shown
	ctx := context.Background()
	var r *rig
	release, judged := make(chan struct{}), make(chan struct{})
	j := &judgeFunc{f: func(ctx context.Context, c *Case, call int) (Outcome, error) {
		if call == 1 {
			r.setTrunks(t, map[string]string{repoA: trunkA2, repoSDK: trunkS}) // the trunk moves while it runs
			defer close(judged)
		} else {
			<-release // the check asked again for the new trunk waits in the stream meanwhile
		}
		return Outcome{Verdict: passing()}, nil
	}}
	r = newRig(t, j)
	r.ch.Candidate(ctx, "feat%2Fx", candidateOf(t, "feat/x", pullOf(repoA, 7, head1)))
	<-judged
	for deadline := time.Now().Add(2 * time.Second); owedState(t, r, repoA, 7, head1) == "" && time.Now().Before(deadline); time.Sleep(time.Millisecond) {
	}
	time.Sleep(20 * time.Millisecond)
	if s := owedState(t, r, repoA, 7, head1); s != "pending" {
		t.Errorf("the status is %q, want pending: the pass was judged on a trunk that moved", s)
	}
	close(release)
	r.ch.Wait()
}