package mock

import (
	"context"
	"log/slog"
	"math/rand"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"git.avsdev.uk/Go/job-search/internal/mock/findatender/ocds"
)

// quiet discards the logging of the Store and Generator it is given to.
var quiet = WithLogger(slog.New(slog.DiscardHandler))

func TestGap(t *testing.T) {
	//nolint:gosec // G404: seeded math/rand keeps the test deterministic
	g := &Generator{
		rng: rand.New(rand.NewSource(1)),
	}
	if d := g.gap(time.Second, time.Second); d != time.Second {
		t.Errorf("min == max: %s", d)
	}
	if d := g.gap(2*time.Second, time.Second); d != 2*time.Second {
		t.Errorf("max < min: %s, want min", d)
	}
	for i := 0; i < 1000; i++ {
		if d := g.gap(time.Second, 2*time.Second); d < time.Second ||
			d > 2*time.Second {
			t.Fatalf("gap out of range: %s", d)
		}
	}
}

func TestScaleValue(t *testing.T) {
	scaleValue(nil, 2) // must not panic

	v := &ocds.Value{
		Amount:   ptr(12345.0),
		Currency: "GBP",
	}
	scaleValue(v, 1.5)
	if *v.Amount != 18500 { // 18517.5 rounded to the nearest 100
		t.Errorf("amount = %v, want 18500", *v.Amount)
	}
	if v.AmountGross != nil {
		t.Error("nil gross amount was set")
	}

	v = &ocds.Value{
		Amount:      ptr(1000.0),
		AmountGross: ptr(1200.0),
	}
	scaleValue(v, 0.5)
	if *v.Amount != 500 || *v.AmountGross != 600 {
		t.Errorf("amounts = %v / %v, want 500 / 600", *v.Amount, *v.AmountGross)
	}
}

func TestEnsurePartyID(t *testing.T) {
	p := ocds.Organization{
		ID:   "GB-EXISTING",
		Name: "Council",
	}
	ensurePartyID(&p)
	if p.ID != "GB-EXISTING" {
		t.Errorf("existing id replaced: %s", p.ID)
	}

	a := ocds.Organization{
		Name: "Somewhere Council",
	}
	b := ocds.Organization{
		Name: "Somewhere Council",
	}
	c := ocds.Organization{
		Name: "Elsewhere Council",
	}
	ensurePartyID(&a)
	ensurePartyID(&b)
	ensurePartyID(&c)
	if !strings.HasPrefix(a.ID, "GB-FTS-") {
		t.Errorf("id = %q", a.ID)
	}
	if a.ID != b.ID {
		t.Errorf("same name gave %s and %s", a.ID, b.ID)
	}
	if a.ID == c.ID {
		t.Errorf("different names gave the same id %s", a.ID)
	}
}

func TestAdvance(t *testing.T) {
	cat := loadTestCatalog(t)
	store, err := OpenStore(filepath.Join(t.TempDir(), "r.jsonl"))
	if err != nil {
		t.Fatal(err)
	}
	defer store.Close()
	g := NewGenerator(cat, store, 1)
	at := time.Date(2026, 10, 8, 12, 0, 0, 0, time.UTC)

	// A planning notice without a tender becomes an active tender.
	r := g.advance(
		ocds.Release{
			OCID: "ocds-x",
			Tag:  []string{"planning"},
		},
		at,
	)
	if r.Tag[0] != "tender" || r.Tender == nil || r.Tender.Status != "active" ||
		r.Tender.TenderPeriod == nil || r.Tender.TenderPeriod.EndDate == nil {
		t.Fatalf("planning -> %v, tender %+v", r.Tag, r.Tender)
	}
	if string(r.Tender.ID) != "ocds-x" || !r.Date.Equal(at) {
		t.Errorf("tender id %s, date %s", r.Tender.ID, r.Date)
	}

	// A tender is either updated (deadline + 14 days) or awarded.
	end := at.AddDate(0, 0, 20)
	prev := ocds.Release{
		OCID: "ocds-y",
		Tag:  []string{"tender"},
		Tender: &ocds.Tender{
			ID: "ocds-y",
			Value: &ocds.Value{
				Amount:   ptr(10000.0),
				Currency: "GBP",
			},
			Lots: []ocds.Lot{
				{
					ID: "1",
				},
				{
					ID: "",
				},
			},
			TenderPeriod: &ocds.Period{
				EndDate: &end,
			},
		},
	}
	seen := map[string]bool{}
	for i := 0; i < 50; i++ {
		r := g.advance(prev, at)
		seen[r.Tag[0]] = true
		switch r.Tag[0] {
		case "tenderUpdate":
			got := *r.Tender.TenderPeriod.EndDate
			if !got.Equal(end.AddDate(0, 0, 14)) {
				t.Fatalf("updated deadline %s", got)
			}
		case "award":
			if r.Tender.Status != "complete" || len(r.Awards) != 1 {
				t.Fatalf("award: status %s, %d awards", r.Tender.Status, len(r.Awards))
			}
			aw := r.Awards[0]
			if aw.Value == nil || *aw.Value.Amount < 8000 ||
				*aw.Value.Amount > 10000 {
				t.Fatalf("award value %+v", aw.Value)
			}
			if len(aw.RelatedLots) != 1 || aw.RelatedLots[0] != "1" {
				t.Fatalf("related lots %v", aw.RelatedLots)
			}
			if len(aw.Suppliers) != 1 || len(r.Parties) != 1 ||
				r.Parties[0].Roles[0] != "supplier" {
				t.Fatalf("suppliers %v, parties %v", aw.Suppliers, r.Parties)
			}
		default:
			t.Fatalf("tender -> %s", r.Tag[0])
		}
	}
	if !seen["tenderUpdate"] || !seen["award"] {
		t.Errorf("expected both updates and awards, saw %v", seen)
	}
	if *prev.Tender.TenderPeriod.EndDate != end || prev.Awards != nil {
		t.Error("advance modified the previous release")
	}

	// An update without a deadline gets 30 + 14 days; a tender with no value
	// is awarded with no value.
	prev = ocds.Release{
		OCID: "ocds-z",
		Tag:  []string{"tender"},
		Tender: &ocds.Tender{
			ID: "ocds-z",
		},
	}
	for i := 0; i < 50; i++ {
		r := g.advance(prev, at)
		switch r.Tag[0] {
		case "tenderUpdate":
			got := *r.Tender.TenderPeriod.EndDate
			if !got.Equal(at.AddDate(0, 0, 44)) {
				t.Fatalf("default deadline %s", got)
			}
		case "award":
			if r.Awards[0].Value != nil {
				t.Fatalf("award value %+v, want nil", r.Awards[0].Value)
			}
		}
	}
}

func TestRunPublishesUntilCancelled(t *testing.T) {
	cat := loadTestCatalog(t)
	store, err := OpenStore(filepath.Join(t.TempDir(), "r.jsonl"), quiet)
	if err != nil {
		t.Fatal(err)
	}
	defer store.Close()

	ctx, cancel := context.WithCancel(context.Background())
	done := make(chan struct{})
	generator := NewGenerator(cat, store, 1, quiet)
	go func() {
		generator.Run(ctx, time.Millisecond, 2*time.Millisecond)
		close(done)
	}()

	deadline := time.After(5 * time.Second)
	for store.Len() < 3 {
		select {
		case <-deadline:
			cancel()
			t.Fatalf("only %d releases published", store.Len())
		case <-time.After(time.Millisecond):
		}
	}
	cancel()
	select {
	case <-done:
	case <-time.After(5 * time.Second):
		t.Fatal("Run did not return after cancel")
	}
}

// A failing store is logged and Run carries on until cancelled.
func TestRunSurvivesStoreErrors(t *testing.T) {
	cat := loadTestCatalog(t)
	store, err := OpenStore(filepath.Join(t.TempDir(), "r.jsonl"))
	if err != nil {
		t.Fatal(err)
	}
	store.Close()

	ctx, cancel := context.WithTimeout(context.Background(), 20*time.Millisecond)
	defer cancel()
	generator := NewGenerator(cat, store, 1, quiet)
	generator.Run(ctx, time.Millisecond, time.Millisecond)
	if store.Len() != 0 {
		t.Errorf("Len = %d, want 0", store.Len())
	}
}