package creator

import (
	"context"
	"errors"
	"testing"
	"time"
)

func TestCreatorPureCoverageGuards(t *testing.T) {
	if _, err := decodeCommentCheckpoint(`{"cursor":"missing-work-key"}`); !errors.Is(err, ErrInvalid) {
		t.Fatalf("invalid empty checkpoint: %v", err)
	}
	if value, err := decodeCommentCheckpoint(`{"work_key":"work","cursor":"cursor"}`); err != nil || value.WorkKey != "work" || value.Cursor != "cursor" {
		t.Fatalf("valid checkpoint: %+v %v", value, err)
	}
}

func TestCreatorSchedulingAndActionPredicates(t *testing.T) {
	now := time.Now().UTC()
	if next, reason := NextMetricAtValue(nil, now, SettingsUpdate{}); !next.IsZero() || reason != "published_at_pending_verification" {
		t.Fatalf("pending metric schedule: %v %q", next, reason)
	}
	published := now.Add(-time.Hour)
	input := SettingsUpdate{MetricInitialIntervalSeconds: 60, MetricMaxIntervalSeconds: 3600, MetricMultiplier: 2, MetricAgeSeconds: 7200}
	if next, reason := NextMetricAtValue(&published, now, input); next.IsZero() || reason != "" {
		t.Fatalf("metric schedule: %v %q", next, reason)
	}
	if coalesceReason("value", "fallback") != "value" || coalesceReason("", "fallback") != "fallback" {
		t.Fatal("coalesceReason did not choose the expected value")
	}
}

func TestCreatorPaginationGuards(t *testing.T) {
	items, err := collectPagesFromCursor(context.Background(), "", func(_ context.Context, cursor string) ([]string, string, bool, error) {
		if cursor != "" {
			t.Fatalf("unexpected cursor %q", cursor)
		}
		return []string{"one"}, "", false, nil
	}, nil)
	if err != nil || len(items) != 1 {
		t.Fatalf("single page: %v %v", items, err)
	}
	for name, fetch := range map[string]func(context.Context, string) ([]string, string, bool, error){
		"missing cursor":  func(context.Context, string) ([]string, string, bool, error) { return nil, "", true, nil },
		"repeated cursor": func(context.Context, string) ([]string, string, bool, error) { return nil, "same", true, nil },
	} {
		_, err := collectPagesFromCursor(context.Background(), "same", fetch, nil)
		if !errors.Is(err, ErrInvalid) {
			t.Fatalf("%s: %v", name, err)
		}
	}
	_, err = collectPagesFromCursor(context.Background(), "", func(context.Context, string) ([]string, string, bool, error) {
		return nil, "next", true, errors.New("fetch failed")
	}, nil)
	if err == nil || err.Error() != "fetch failed" {
		t.Fatalf("fetch failure: %v", err)
	}
	_, err = collectPagesFromCursor(context.Background(), "", func(context.Context, string) ([]string, string, bool, error) {
		return []string{"one"}, "next", true, nil
	}, func([]string, string, bool) error { return errors.New("save failed") })
	if err == nil || err.Error() != "save failed" {
		t.Fatalf("after-page failure: %v", err)
	}
}

func TestConfiguredBailianWithoutStore(t *testing.T) {
	var client *ConfiguredBailian
	if _, err := client.Generate(context.Background(), "instruction", "input"); !errors.Is(err, ErrUnavailable) {
		t.Fatalf("nil Generate: %v", err)
	}
	if _, _, err := client.MatchTheme(context.Background(), "title", "body", "topic"); !errors.Is(err, ErrUnavailable) {
		t.Fatalf("nil MatchTheme: %v", err)
	}
	if _, _, err := client.MatchLead(context.Background(), "work", "comment", "requirement"); !errors.Is(err, ErrUnavailable) {
		t.Fatalf("nil MatchLead: %v", err)
	}
}