package httpapi_test

import (
	"context"
	"encoding/json"
	"io"
	"log/slog"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"git.vakhrushev.me/av/jellybit/internal/httpapi"
	"git.vakhrushev.me/av/jellybit/internal/ingest"
	"git.vakhrushev.me/av/jellybit/internal/store"
)

type fakeIngestor struct {
	res     ingest.Result
	err     error
	lastReq ingest.Request
}

func (f *fakeIngestor) Ingest(_ context.Context, req ingest.Request) (ingest.Result, error) {
	f.lastReq = req
	return f.res, f.err
}

type fakeCommander struct {
	cancelled []int64
	retried   []int64
	err       error
}

func (f *fakeCommander) Cancel(_ context.Context, id int64) error {
	if f.err != nil {
		return f.err
	}
	f.cancelled = append(f.cancelled, id)
	return nil
}

func (f *fakeCommander) Retry(_ context.Context, id int64) error {
	if f.err != nil {
		return f.err
	}
	f.retried = append(f.retried, id)
	return nil
}

type fakeReader struct {
	list []store.Download
	get  *store.Download
}

func (f *fakeReader) ListDownloads(_ context.Context) ([]store.Download, error) { return f.list, nil }

func (f *fakeReader) GetDownload(_ context.Context, id int64) (*store.Download, error) {
	if f.get != nil {
		return f.get, nil
	}
	return &store.Download{ID: id, State: store.StateCancelled}, nil
}

func newServer(t *testing.T, d httpapi.Deps) *httptest.Server {
	t.Helper()
	if d.Logger == nil {
		d.Logger = slog.New(slog.NewTextHandler(io.Discard, nil))
	}
	h, err := httpapi.NewRouter(d)
	if err != nil {
		t.Fatalf("NewRouter: %v", err)
	}
	srv := httptest.NewServer(h)
	t.Cleanup(srv.Close)
	return srv
}

func TestAPIAdd(t *testing.T) {
	ing := &fakeIngestor{res: ingest.Result{DownloadID: 1, Infohash: "abc", State: store.StateDownloading}}
	srv := newServer(t, httpapi.Deps{Ingestor: ing, Commander: &fakeCommander{}, Reader: &fakeReader{}})

	resp, err := http.Post(srv.URL+"/api/downloads", "application/json",
		strings.NewReader(`{"source":"magnet:?xt=urn:btih:abc","context":"Дюна"}`))
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusCreated {
		t.Fatalf("status = %d, want 201", resp.StatusCode)
	}
	var got map[string]any
	_ = json.NewDecoder(resp.Body).Decode(&got)
	if got["id"].(float64) != 1 || got["state"] != "downloading" {
		t.Errorf("body = %v", got)
	}
	if ing.lastReq.Context != "Дюна" {
		t.Errorf("контекст не проброшен: %q", ing.lastReq.Context)
	}
}

func TestAPIAddBadInput(t *testing.T) {
	ing := &fakeIngestor{err: ingestErr("bad magnet")}
	srv := newServer(t, httpapi.Deps{Ingestor: ing, Commander: &fakeCommander{}, Reader: &fakeReader{}})

	resp, err := http.Post(srv.URL+"/api/downloads", "application/json", strings.NewReader(`{"source":"x"}`))
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusBadRequest {
		t.Fatalf("status = %d, want 400", resp.StatusCode)
	}
}

func TestAPIList(t *testing.T) {
	reader := &fakeReader{list: []store.Download{
		{ID: 2, SourceType: store.SourceMagnet, State: store.StateCompleted, Infohash: store.NullString("abc")},
		{ID: 1, SourceType: store.SourceMagnet, State: store.StateDownloading},
	}}
	srv := newServer(t, httpapi.Deps{Ingestor: &fakeIngestor{}, Commander: &fakeCommander{}, Reader: reader})

	resp, err := http.Get(srv.URL + "/api/downloads")
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()
	var got []map[string]any
	_ = json.NewDecoder(resp.Body).Decode(&got)
	if len(got) != 2 {
		t.Fatalf("len = %d, want 2", len(got))
	}
	if got[0]["state"] != "completed" || got[0]["infohash"] != "abc" {
		t.Errorf("first = %v", got[0])
	}
}

func TestAPICancel(t *testing.T) {
	cmd := &fakeCommander{}
	srv := newServer(t, httpapi.Deps{Ingestor: &fakeIngestor{}, Commander: cmd, Reader: &fakeReader{}})

	resp, err := http.Post(srv.URL+"/api/downloads/5/cancel", "", nil)
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("status = %d, want 200", resp.StatusCode)
	}
	if len(cmd.cancelled) != 1 || cmd.cancelled[0] != 5 {
		t.Errorf("cancel вызван неверно: %v", cmd.cancelled)
	}
}

func TestIndexRenders(t *testing.T) {
	reader := &fakeReader{list: []store.Download{
		{ID: 1, SourceType: store.SourceMagnet, SourceRef: "magnet:?xt=urn:btih:abc", State: store.StateDownloading},
	}}
	srv := newServer(t, httpapi.Deps{Ingestor: &fakeIngestor{}, Commander: &fakeCommander{}, Reader: reader})

	resp, err := http.Get(srv.URL + "/")
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()
	body, _ := io.ReadAll(resp.Body)
	if resp.StatusCode != http.StatusOK {
		t.Fatalf("status = %d", resp.StatusCode)
	}
	if !strings.Contains(string(body), "jellybit") || !strings.Contains(string(body), "downloading") {
		t.Error("страница не содержит ожидаемого контента")
	}
}

type ingestErr string

func (e ingestErr) Error() string { return string(e) }