package server_test

import (
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"
	"os"
	"strings"
	"testing"
	"time"

	"notashelf.dev/ncro/internal/cache"
	"notashelf.dev/ncro/internal/config"
	"notashelf.dev/ncro/internal/prober"
	"notashelf.dev/ncro/internal/router"
	"notashelf.dev/ncro/internal/server"
)

func makeTestServer(t *testing.T, upstreams ...string) *httptest.Server {
	t.Helper()
	f, _ := os.CreateTemp("", "ncro-srv-*.db")
	f.Close()
	t.Cleanup(func() { os.Remove(f.Name()) })

	db, err := cache.Open(f.Name(), 1000)
	if err != nil {
		t.Fatal(err)
	}
	t.Cleanup(func() { db.Close() })

	p := prober.New(0.3)
	for _, u := range upstreams {
		p.RecordLatency(u, 10)
	}

	upsCfg := make([]config.UpstreamConfig, len(upstreams))
	for i, u := range upstreams {
		upsCfg[i] = config.UpstreamConfig{URL: u}
	}

	r := router.New(db, p, time.Hour, 5*time.Second)
	return httptest.NewServer(server.New(r, p, upsCfg))
}

func TestNixCacheInfo(t *testing.T) {
	ts := makeTestServer(t)
	defer ts.Close()

	resp, err := http.Get(ts.URL + "/nix-cache-info")
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		t.Errorf("status = %d, want 200", resp.StatusCode)
	}
	body, _ := io.ReadAll(resp.Body)
	if !strings.Contains(string(body), "StoreDir:") {
		t.Errorf("body missing StoreDir: %q", body)
	}
}

func TestHealthEndpoint(t *testing.T) {
	ts := makeTestServer(t)
	defer ts.Close()

	resp, err := http.Get(ts.URL + "/health")
	if err != nil {
		t.Fatal(err)
	}
	if resp.StatusCode != 200 {
		t.Errorf("status = %d, want 200", resp.StatusCode)
	}
}

func TestNarinfoProxy(t *testing.T) {
	upstream := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if strings.HasSuffix(r.URL.Path, ".narinfo") {
			w.Header().Set("Content-Type", "text/x-nix-narinfo")
			fmt.Fprint(w, "StorePath: /nix/store/abc123-hello-2.12\nURL: nar/abc123.nar\nCompression: none\n")
			return
		}
		w.WriteHeader(404)
	}))
	defer upstream.Close()

	ts := makeTestServer(t, upstream.URL)
	defer ts.Close()

	resp, err := http.Get(ts.URL + "/abc123def456.narinfo")
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()

	if resp.StatusCode != 200 {
		t.Errorf("narinfo status = %d, want 200", resp.StatusCode)
	}
	body, _ := io.ReadAll(resp.Body)
	if !strings.Contains(string(body), "StorePath:") {
		t.Errorf("expected narinfo body, got: %q", body)
	}
}

func TestNarinfoNotFound(t *testing.T) {
	upstream := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(404)
	}))
	defer upstream.Close()

	ts := makeTestServer(t, upstream.URL)
	defer ts.Close()

	resp, _ := http.Get(ts.URL + "/notfound000000.narinfo")
	if resp.StatusCode != 404 {
		t.Errorf("status = %d, want 404", resp.StatusCode)
	}
}

func TestNARStreamingPassthrough(t *testing.T) {
	narContent := []byte("fake-nar-content-bytes")
	upstream := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if strings.HasPrefix(r.URL.Path, "/nar/") {
			w.Header().Set("Content-Type", "application/x-nix-archive")
			w.Write(narContent)
			return
		}
		if strings.HasSuffix(r.URL.Path, ".narinfo") {
			w.WriteHeader(200)
			return
		}
		w.WriteHeader(404)
	}))
	defer upstream.Close()

	ts := makeTestServer(t, upstream.URL)
	defer ts.Close()

	resp, err := http.Get(ts.URL + "/nar/abc123.nar")
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()
	if resp.StatusCode != 200 {
		t.Errorf("NAR status = %d, want 200", resp.StatusCode)
	}
	body, _ := io.ReadAll(resp.Body)
	if string(body) != string(narContent) {
		t.Errorf("NAR body mismatch: got %q, want %q", body, narContent)
	}
}