package llamaswap

import (
	"context"
	"encoding/base64"
	"encoding/json"
	"errors"
	"net/http"
	"net/http/httptest"
	"reflect"
	"testing"

	"gitea.stevedudenhoeffer.com/steve/majordomo/llm"
	"gitea.stevedudenhoeffer.com/steve/majordomo/videogen"
)

func TestSubmitChain(t *testing.T) {
	var gotPath string
	var gotBody map[string]any
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		gotPath = r.URL.Path
		_ = json.NewDecoder(r.Body).Decode(&gotBody)
		_, _ = w.Write([]byte(`{"job_id":"job-123"}`))
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, err := p.ChainerModel("videoutils")
	if err != nil {
		t.Fatalf("ChainerModel: %v", err)
	}
	jobID, err := ch.SubmitChain(context.Background(), videogen.ChainRequest{
		Segments: []videogen.ChainSegment{
			{Prompt: "a cat walks in", Seconds: 5},
			{Prompt: "the cat sits down", Seconds: 5},
		},
		InitImage:   []byte("IMG"),
		SmoothJoins: true,
		Size:        "1280x704",
	})
	if err != nil {
		t.Fatalf("SubmitChain: %v", err)
	}
	if jobID != "job-123" {
		t.Errorf("jobID = %q", jobID)
	}
	if gotPath != "/upstream/videoutils/v1/video/chain" {
		t.Errorf("path = %q", gotPath)
	}
	segments, _ := gotBody["segments"].([]any)
	if len(segments) != 2 {
		t.Fatalf("segments = %v", gotBody["segments"])
	}
	first, _ := segments[0].(map[string]any)
	if first["prompt"] != "a cat walks in" || first["seconds"] != 5.0 {
		t.Errorf("segment[0] = %v", first)
	}
	if gotBody["init_image_b64"] != base64.StdEncoding.EncodeToString([]byte("IMG")) {
		t.Errorf("init_image_b64 = %v", gotBody["init_image_b64"])
	}
	if gotBody["smooth_joins"] != true || gotBody["size"] != "1280x704" {
		t.Errorf("smooth_joins/size = %v/%v", gotBody["smooth_joins"], gotBody["size"])
	}
}

func TestSubmitChainOmitsUnsetFields(t *testing.T) {
	var gotBody map[string]any
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_ = json.NewDecoder(r.Body).Decode(&gotBody)
		_, _ = w.Write([]byte(`{"data":{"job_id":"job-9"}}`)) // data-wrapped envelope
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, _ := p.ChainerModel("videoutils")
	jobID, err := ch.SubmitChain(context.Background(), videogen.ChainRequest{
		Segments: []videogen.ChainSegment{{Prompt: "a dog"}},
	})
	if err != nil {
		t.Fatalf("SubmitChain: %v", err)
	}
	if jobID != "job-9" {
		t.Errorf("jobID = %q, want data-wrapped id", jobID)
	}
	for _, k := range []string{"init_image_b64", "smooth_joins", "size"} {
		if v, ok := gotBody[k]; ok {
			t.Errorf("unset request sent %q = %v, want omitted", k, v)
		}
	}
	seg, _ := gotBody["segments"].([]any)
	if first, _ := seg[0].(map[string]any); first == nil {
		t.Fatalf("segments = %v", gotBody["segments"])
	} else if _, ok := first["seconds"]; ok {
		t.Error("zero seconds sent; want omitted")
	}
}

func TestSubmitChainRejectsBadArgs(t *testing.T) {
	p := New(WithBaseURL("http://unused"))
	ch, _ := p.ChainerModel("videoutils")
	if _, err := ch.SubmitChain(context.Background(), videogen.ChainRequest{}); !errors.Is(err, llm.ErrUnsupported) {
		t.Errorf("no segments: err = %v, want ErrUnsupported", err)
	}
	if _, err := ch.SubmitChain(context.Background(), videogen.ChainRequest{
		Segments: []videogen.ChainSegment{{Prompt: "  "}},
	}); !errors.Is(err, llm.ErrUnsupported) {
		t.Errorf("empty prompt: err = %v, want ErrUnsupported", err)
	}
	if _, err := ch.SubmitChain(context.Background(), videogen.ChainRequest{
		Segments: []videogen.ChainSegment{{Prompt: "x", Seconds: -1}},
	}); !errors.Is(err, llm.ErrUnsupported) {
		t.Errorf("negative seconds: err = %v, want ErrUnsupported", err)
	}
}

func TestSubmitChainRejectsMissingJobID(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_, _ = w.Write([]byte(`{"ok":true}`))
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, _ := p.ChainerModel("videoutils")
	_, err := ch.SubmitChain(context.Background(), videogen.ChainRequest{
		Segments: []videogen.ChainSegment{{Prompt: "x"}},
	})
	var apiErr *llm.APIError
	if !errors.As(err, &apiErr) {
		t.Fatalf("err = %v, want APIError for missing job_id", err)
	}
}

func TestChainStatus(t *testing.T) {
	var gotPath string
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		gotPath = r.URL.Path
		_, _ = w.Write([]byte(`{"status":"running","segment":2,"total":3,"segments":["seg-0"]}`))
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, _ := p.ChainerModel("videoutils")
	job, err := ch.ChainStatus(context.Background(), "job-123")
	if err != nil {
		t.Fatalf("ChainStatus: %v", err)
	}
	if gotPath != "/upstream/videoutils/v1/jobs/job-123" {
		t.Errorf("path = %q", gotPath)
	}
	if job.Status != "running" || job.Segment != 2 || job.Total != 3 {
		t.Errorf("job = %+v", job)
	}
	if !reflect.DeepEqual(job.SegmentIDs, []string{"seg-0"}) {
		t.Errorf("SegmentIDs = %v", job.SegmentIDs)
	}
	if job.Raw == nil {
		t.Error("Raw = nil, want raw payload")
	}
}

func TestChainStatusToleratesObjectSegments(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_, _ = w.Write([]byte(`{"status":"done","segment":2,"total":2,"segments":[{"id":"seg-0"},{"segment_id":"seg-1"}]}`))
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, _ := p.ChainerModel("videoutils")
	job, err := ch.ChainStatus(context.Background(), "job-123")
	if err != nil {
		t.Fatalf("ChainStatus: %v", err)
	}
	if !reflect.DeepEqual(job.SegmentIDs, []string{"seg-0", "seg-1"}) {
		t.Errorf("SegmentIDs = %v", job.SegmentIDs)
	}
}

func TestChainStatusRejectsStatuslessPayload(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		_, _ = w.Write([]byte(`{"detail":"no such job"}`))
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, _ := p.ChainerModel("videoutils")
	_, err := ch.ChainStatus(context.Background(), "job-123")
	var apiErr *llm.APIError
	if !errors.As(err, &apiErr) {
		t.Fatalf("err = %v, want APIError for statusless payload", err)
	}
}

func TestChainJobPathRejectsHostileIDs(t *testing.T) {
	p := New(WithBaseURL("http://unused"))
	ch, _ := p.ChainerModel("videoutils")
	for _, bad := range []string{"", "a/b", "a?b", "a#b", "..", "a..b"} {
		if _, err := ch.ChainStatus(context.Background(), bad); err == nil {
			t.Errorf("ChainStatus(%q) succeeded; want error", bad)
		}
		if _, err := ch.ChainResult(context.Background(), bad); err == nil {
			t.Errorf("ChainResult(%q) succeeded; want error", bad)
		}
	}
}

func TestChainResult(t *testing.T) {
	var gotPath string
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		gotPath = r.URL.Path
		w.Header().Set("Content-Type", "video/mp4")
		_, _ = w.Write(mp4Fixture())
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, _ := p.ChainerModel("videoutils")
	res, err := ch.ChainResult(context.Background(), "job-123")
	if err != nil {
		t.Fatalf("ChainResult: %v", err)
	}
	if gotPath != "/upstream/videoutils/v1/jobs/job-123/result" {
		t.Errorf("path = %q", gotPath)
	}
	if res.Video.MIME != "video/mp4" || len(res.Video.Data) == 0 {
		t.Fatalf("video = %q/%d bytes", res.Video.MIME, len(res.Video.Data))
	}
}

func TestChainSegmentResult(t *testing.T) {
	var gotPath string
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		gotPath = r.URL.Path
		w.Header().Set("Content-Type", "video/mp4")
		_, _ = w.Write(mp4Fixture())
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, _ := p.ChainerModel("videoutils")
	res, err := ch.ChainSegmentResult(context.Background(), "job-123", 1)
	if err != nil {
		t.Fatalf("ChainSegmentResult: %v", err)
	}
	if gotPath != "/upstream/videoutils/v1/jobs/job-123/segments/1" {
		t.Errorf("path = %q", gotPath)
	}
	if res.Video.MIME != "video/mp4" {
		t.Fatalf("video = %q", res.Video.MIME)
	}

	if _, err := ch.ChainSegmentResult(context.Background(), "job-123", -1); !errors.Is(err, llm.ErrUnsupported) {
		t.Errorf("negative segment: err = %v, want ErrUnsupported", err)
	}
}

func TestChainResultRejectsNonVideoResponse(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Header().Set("Content-Type", "application/json")
		_, _ = w.Write([]byte(`{"status":"running"}`)) // a status page, not the clip
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, _ := p.ChainerModel("videoutils")
	_, err := ch.ChainResult(context.Background(), "job-123")
	var apiErr *llm.APIError
	if !errors.As(err, &apiErr) {
		t.Fatalf("err = %v, want APIError for non-video body", err)
	}
}

func TestChainSurfacesAPIError(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusNotFound)
		_, _ = w.Write([]byte(`{"error":{"message":"job not found"}}`))
	}))
	defer srv.Close()

	p := New(WithBaseURL(srv.URL), WithHTTPClient(srv.Client()))
	ch, _ := p.ChainerModel("videoutils")
	_, err := ch.ChainStatus(context.Background(), "job-void")
	var apiErr *llm.APIError
	if !errors.As(err, &apiErr) {
		t.Fatalf("err = %T %v, want *llm.APIError", err, err)
	}
	if apiErr.Status != http.StatusNotFound || apiErr.Message != "job not found" || apiErr.Model != "videoutils" {
		t.Errorf("apiErr = %+v", apiErr)
	}
}