package adapters

import (
	"context"
	"errors"
	"testing"

	oppintel "github.com/missionworkforce/missionmatch/internal/modules/opportunity_intelligence"
	"github.com/missionworkforce/missionmatch/internal/platform/marketintel"
)

// fakeProvider serves fixed pages and can simulate a throttle on a given page, so the adapter paging
// and graceful stop are tested without any network.
type fakeProvider struct {
	pages          [][]marketintel.Award
	throttleAtPage int // 1 based; 0 means never
	calls          int
}

func (f *fakeProvider) Name() string { return "USASpending" }

func (f *fakeProvider) FetchAwards(_ context.Context, q marketintel.AwardQuery) ([]marketintel.Award, bool, error) {
	f.calls++
	if f.throttleAtPage != 0 && q.Page == f.throttleAtPage {
		return nil, false, marketintel.ErrThrottled
	}
	idx := q.Page - 1
	if idx < 0 || idx >= len(f.pages) {
		return nil, false, nil
	}
	return f.pages[idx], idx < len(f.pages)-1, nil
}

func TestUSASpendingSourceFetchPaginates(t *testing.T) {
	fp := &fakeProvider{pages: [][]marketintel.Award{
		{{GeneratedInternalID: "A1", AwardID: "P1"}, {GeneratedInternalID: "A2", AwardID: "P2"}},
		{{GeneratedInternalID: "A3", AwardID: "P3"}},
	}}
	src := NewUSASpendingSource(fp, marketintel.AwardQuery{}, 5)
	var got []oppintel.OpportunityRecord
	err := src.Fetch(context.Background(), func(r oppintel.OpportunityRecord) error {
		got = append(got, r)
		return nil
	})
	if err != nil {
		t.Fatalf("Fetch: %v", err)
	}
	if len(got) != 3 {
		t.Fatalf("want 3 records across pages, got %d", len(got))
	}
	for _, r := range got {
		if r.Kind != oppintel.KindContractAward || r.SourceName != "USASpending" {
			t.Fatalf("record wrong: %+v", r)
		}
	}
}

func TestUSASpendingSourceThrottleSoftStop(t *testing.T) {
	fp := &fakeProvider{
		pages:          [][]marketintel.Award{{{GeneratedInternalID: "A1", AwardID: "P1"}}, {{GeneratedInternalID: "A2"}}},
		throttleAtPage: 2,
	}
	src := NewUSASpendingSource(fp, marketintel.AwardQuery{}, 5)
	var got int
	err := src.Fetch(context.Background(), func(oppintel.OpportunityRecord) error {
		got++
		return nil
	})
	if !errors.Is(err, oppintel.ErrThrottled) {
		t.Fatalf("want ErrThrottled, got %v", err)
	}
	if got != 1 {
		t.Fatalf("want 1 record before the throttle, got %d", got)
	}
}

func TestUSASpendingSourceYieldErrorStops(t *testing.T) {
	fp := &fakeProvider{pages: [][]marketintel.Award{{{GeneratedInternalID: "A1"}, {GeneratedInternalID: "A2"}}}}
	src := NewUSASpendingSource(fp, marketintel.AwardQuery{}, 5)
	boom := errors.New("boom")
	err := src.Fetch(context.Background(), func(oppintel.OpportunityRecord) error { return boom })
	if !errors.Is(err, boom) {
		t.Fatalf("want the yield error, got %v", err)
	}
}