package normalize

import (
	"context"
	"errors"
	"strings"
	"testing"
	"time"

	"gitea.maximumdirect.net/ejr/feedkit/event"
)

func TestProcessorFirstMatchWins(t *testing.T) {
	var firstCalls, secondCalls int

	p := NewProcessor([]Normalizer{
		Func{
			MatchFn: func(event.Event) bool { return true },
			NormalizeFn: func(_ context.Context, in event.Event) (*event.Event, error) {
				firstCalls++
				out := in
				out.Schema = "normalized.first.v1"
				return &out, nil
			},
		},
		Func{
			MatchFn: func(event.Event) bool { return true },
			NormalizeFn: func(_ context.Context, in event.Event) (*event.Event, error) {
				secondCalls++
				out := in
				out.Schema = "normalized.second.v1"
				return &out, nil
			},
		},
	}, false)

	out, err := p.Process(context.Background(), testEvent())
	if err != nil {
		t.Fatalf("Process error: %v", err)
	}
	if out == nil {
		t.Fatalf("expected output event, got nil")
	}
	if out.Schema != "normalized.first.v1" {
		t.Fatalf("unexpected schema: %q", out.Schema)
	}
	if firstCalls != 1 {
		t.Fatalf("expected first normalizer called once, got %d", firstCalls)
	}
	if secondCalls != 0 {
		t.Fatalf("expected second normalizer skipped, got %d calls", secondCalls)
	}
}

func TestProcessorNoMatchPassThroughAndRequireMatch(t *testing.T) {
	in := testEvent()
	in.Schema = "raw.schema.v1"

	passThrough := NewProcessor([]Normalizer{
		Func{
			MatchFn: func(event.Event) bool { return false },
			NormalizeFn: func(_ context.Context, in event.Event) (*event.Event, error) {
				out := in
				out.Schema = "should.not.run"
				return &out, nil
			},
		},
	}, false)

	out, err := passThrough.Process(context.Background(), in)
	if err != nil {
		t.Fatalf("pass-through Process error: %v", err)
	}
	if out == nil {
		t.Fatalf("expected pass-through output event, got nil")
	}
	if out.Schema != "raw.schema.v1" {
		t.Fatalf("expected unchanged schema, got %q", out.Schema)
	}

	required := NewProcessor(nil, true)
	_, err = required.Process(context.Background(), in)
	if err == nil {
		t.Fatalf("expected require-match error")
	}
	if !strings.Contains(err.Error(), "no normalizer matched") {
		t.Fatalf("unexpected error: %v", err)
	}
}

func TestProcessorDropAndErrorPropagation(t *testing.T) {
	t.Run("drop", func(t *testing.T) {
		p := NewProcessor([]Normalizer{
			Func{
				MatchFn: func(event.Event) bool { return true },
				NormalizeFn: func(context.Context, event.Event) (*event.Event, error) {
					return nil, nil
				},
			},
		}, false)

		out, err := p.Process(context.Background(), testEvent())
		if err != nil {
			t.Fatalf("Process error: %v", err)
		}
		if out != nil {
			t.Fatalf("expected nil output for dropped event, got %#v", out)
		}
	})

	t.Run("error", func(t *testing.T) {
		p := NewProcessor([]Normalizer{
			Func{
				MatchFn: func(event.Event) bool { return true },
				NormalizeFn: func(context.Context, event.Event) (*event.Event, error) {
					return nil, errors.New("map failed")
				},
			},
		}, false)

		_, err := p.Process(context.Background(), testEvent())
		if err == nil {
			t.Fatalf("expected error")
		}
		if !strings.Contains(err.Error(), "normalizer failed") {
			t.Fatalf("unexpected error: %v", err)
		}
	})
}

func testEvent() event.Event {
	return event.Event{
		ID:        "evt-normalize-1",
		Kind:      event.Kind("observation"),
		Source:    "source-1",
		EmittedAt: time.Now().UTC(),
		Payload:   map[string]any{"x": 1},
	}
}