package server

import (
	"os"
	"path/filepath"
	"slices"
	"strings"
	"testing"

	"gopkg.in/yaml.v3"
)

// The publish gate (rule 177, M462 #4984), pinned. release.yml holds every
// verifying lane and every publishing job in one graph so that a publish can
// depend on the lanes; these tests keep that dependency from eroding.
//
// The failure each one guards against is silent. A lane added without being
// named in a publisher's needs runs, goes red, and :dev publishes anyway. A
// condition relaxed to `!failure()` lets a lane that never started count as
// a pass. Neither shows up as a broken build — only as a gate that no longer
// gates.

// gateLanes are the verifying jobs. Every publisher must need each of them and
// require its success by name.
var gateLanes = []string{"go", "integration", "web", "android", "govulncheck"}

// gatePublishers push something other people can pull: image tags, and the
// APK + sidecar attached to a Release.
var gatePublishers = []string{"image-release", "release-assets"}

// gateOthers are the remaining jobs and why they sit outside the gate:
// android-release only builds a workflow artifact (nothing outside the run can
// pull it), and verify-release reports on a finished release.
var gateOthers = []string{"android-release", "verify-release"}

type workflowJob struct {
	Needs any    `yaml:"needs"`
	If    string `yaml:"if"`
}

func releaseJobs(t *testing.T) map[string]workflowJob {
	t.Helper()
	body, err := os.ReadFile(filepath.Join(repoRoot(t), ".gitea", "workflows", "release.yml"))
	if err != nil {
		t.Fatal(err)
	}
	var wf struct {
		Jobs map[string]workflowJob `yaml:"jobs"`
	}
	if err := yaml.Unmarshal(body, &wf); err != nil {
		t.Fatalf("parse release.yml: %v", err)
	}
	if len(wf.Jobs) == 0 {
		t.Fatal("release.yml has no jobs")
	}
	return wf.Jobs
}

func jobNeeds(j workflowJob) []string {
	switch v := j.Needs.(type) {
	case string:
		return []string{v}
	case []any:
		out := make([]string, 0, len(v))
		for _, n := range v {
			if s, ok := n.(string); ok {
				out = append(out, s)
			}
		}
		return out
	}
	return nil
}

// A job nobody has classified is the case that matters: a new lane that was
// never added to the publishers' needs.
func TestReleaseGate_EveryJobIsClassified(t *testing.T) {
	for name := range releaseJobs(t) {
		if slices.Contains(gateLanes, name) || slices.Contains(gatePublishers, name) || slices.Contains(gateOthers, name) {
			continue
		}
		t.Errorf("release.yml job %q is not classified. If it verifies, add it to gateLanes and to every publisher's needs and if; "+
			"if it publishes, add it to gatePublishers and gate it; otherwise add it to gateOthers with the reason", name)
	}
	for _, want := range append(append(slices.Clone(gateLanes), gatePublishers...), gateOthers...) {
		if _, ok := releaseJobs(t)[want]; !ok {
			t.Errorf("release.yml has no %q job, which this test expects", want)
		}
	}
}

func TestReleaseGate_PublishersNeedEveryLaneToSucceed(t *testing.T) {
	jobs := releaseJobs(t)
	for _, pub := range gatePublishers {
		job, ok := jobs[pub]
		if !ok {
			t.Errorf("no %q job", pub)
			continue
		}
		needs := jobNeeds(job)
		cond := strings.Join(strings.Fields(job.If), " ")
		for _, lane := range gateLanes {
			if !slices.Contains(needs, lane) {
				t.Errorf("%s does not need %q: it can publish without waiting for that lane", pub, lane)
			}
			if !strings.Contains(cond, "needs."+lane+".result == 'success'") {
				t.Errorf("%s's if does not require needs.%s.result == 'success': a skipped or failed %s would not stop it\n  if: %s",
					pub, lane, lane, cond)
			}
		}
		// always() and failure() both make a job run past a red dependency;
		// !cancelled() is fine only because the per-lane success checks above
		// carry the gate.
		for _, forbidden := range []string{"always()", "failure()"} {
			if strings.Contains(cond, forbidden) {
				t.Errorf("%s's if uses %s, which runs it past a failed lane\n  if: %s", pub, forbidden, cond)
			}
		}
	}
}