//go:build integration

package main

import (
	"encoding/json"
	"fmt"
	"strings"
	"sync"
	"testing"
)

// Issue 1781 (ADR 0493 §1, §2, §4), the module whole over a real bus: a milestone made by its verb is kept in the
// state the manifest declares, and two instances linking one issue to two milestones at the same moment leave it in
// exactly one; the other is refused naming the first, and the milestones and the list say the same.
func TestAnIssueRaceIntoTwoMilestonesOverTheBusEndsInOne(t *testing.T) {
	b := newBus(t)
	var events []event
	var evMu sync.Mutex
	settings := writeSettings(t, 365)
	one, two := b.start(t, settings, &events, &evMu), b.start(t, settings, &events, &evMu)
	must := func(raw json.RawMessage, err error) json.RawMessage {
		t.Helper()
		if err != nil {
			t.Fatal(err)
		}
		return raw
	}
	must(one.call("open", map[string]any{"title": "a milestone's issue", "report": "seen"}))
	must(one.call("milestone-set", map[string]any{"design": 47, "id": "R6", "outcome": "nodes apply their wants", "order": 1}))
	must(two.call("milestone-set", map[string]any{"design": 47, "id": "3 fix", "outcome": "a group merges in one pass", "order": 2}))
	errs := make([]error, 2)
	var wg sync.WaitGroup
	for k, c := range []struct {
		i      *instance
		target string
	}{{one, "47/R6"}, {two, "47/3-fix"}} {
		wg.Add(1)
		go func() {
			defer wg.Done()
			_, errs[k] = c.i.call("link", map[string]any{"number": 365, "kind": "milestone", "target": c.target})
		}()
	}
	wg.Wait()
	if (errs[0] == nil) == (errs[1] == nil) {
		t.Fatalf("both or neither linked: %v", errs)
	}
	refused := errs[0]
	if refused == nil {
		refused = errs[1]
	}
	if !strings.Contains(refused.Error(), "is in milestone") {
		t.Fatalf("refused with %v", refused)
	}
	var read MilestonesRead
	_ = json.Unmarshal(must(two.call("milestones", map[string]any{"design": 47})), &read)
	if len(read.Milestones) != 2 || read.Milestones[0].ID != "R6" || read.Milestones[1].ID != "3-fix" ||
		len(read.Milestones[0].Issues)+len(read.Milestones[1].Issues) != 1 {
		t.Fatalf("%+v", read.Milestones)
	}
	in := "47/R6"
	if len(read.Milestones[1].Issues) == 1 {
		in = "47/3-fix"
	}
	var l Listed
	_ = json.Unmarshal(must(one.call("list", map[string]any{"linked": "milestone:" + in})), &l)
	if len(l.Rows) != 1 || l.Rows[0].Number != 365 {
		t.Fatalf("listed %+v", l)
	}
	var hist MilestonesRead
	_ = json.Unmarshal(must(one.call("milestones", map[string]any{"one": "47/R6"})), &hist)
	if len(hist.History) != 1 {
		t.Fatalf("history %d values", len(hist.History))
	}
	// The moves history over the real log: the open, from nothing to open, read by the other instance.
	var ch ChangesRead
	_ = json.Unmarshal(must(two.call("changes", map[string]any{"since": "60m"})), &ch)
	if len(ch.Changes) != 1 || ch.Changes[0].Number != 365 || ch.Changes[0].Kind != OpOpened || ch.Changes[0].To != StatusOpen ||
		ch.Changes[0].Title != "a milestone's issue" {
		t.Fatalf("changes %+v", ch)
	}
	evMu.Lock()
	defer evMu.Unlock()
	var kinds []string
	for _, e := range events {
		kinds = append(kinds, e.Key)
	}
	if fmt.Sprint(kinds) != "[opened milestone-set milestone-set linked]" {
		t.Fatalf("events %v", kinds)
	}
}