package api_test

import (
	"context"
	"encoding/base64"
	"encoding/json"
	"io"
	"net/http"
	"net/http/httptest"
	"path/filepath"
	"strings"
	"testing"

	"wh/api"
	"wh/config"
	"wh/store"
	"wh/web"
)

// newSite starts the API with the web front end mounted, as cmd/server does.
func newSite(t *testing.T) (*httptest.Server, config.Config) {
	t.Helper()
	cfg := config.Default()
	st, err := store.Open("sqlite:" + filepath.Join(t.TempDir(), "t.db"))
	if err != nil {
		t.Fatal(err)
	}
	t.Cleanup(func() { st.Close() })
	if err := st.Migrate(context.Background()); err != nil {
		t.Fatal(err)
	}
	mux := api.New(st, cfg)
	mux.Handle("/", web.Handler())
	srv := httptest.NewServer(mux)
	t.Cleanup(srv.Close)
	return srv, cfg
}

func get(t *testing.T, url string) (*http.Response, string) {
	t.Helper()
	resp, err := http.Get(url)
	if err != nil {
		t.Fatal(err)
	}
	defer resp.Body.Close()
	b, _ := io.ReadAll(resp.Body)
	return resp, string(b)
}

func TestInfoAndAssemble(t *testing.T) {
	srv, cfg := newSite(t)

	_, body := get(t, srv.URL+"/info")
	var info struct {
		ProgramBytes int      `json:"program_bytes"`
		CommBytes    int      `json:"comm_bytes"`
		Ores         []string `json:"ores"`
	}
	if err := json.Unmarshal([]byte(body), &info); err != nil {
		t.Fatal(err)
	}
	if info.ProgramBytes != cfg.ProgramBytes || info.CommBytes != cfg.CommBytes || len(info.Ores) != 4 {
		t.Fatalf("info = %+v", info)
	}

	post := func(src string) (int, map[string]any) {
		resp, err := http.Post(srv.URL+"/assemble", "text/plain", strings.NewReader(src))
		if err != nil {
			t.Fatal(err)
		}
		defer resp.Body.Close()
		var m map[string]any
		json.NewDecoder(resp.Body).Decode(&m)
		return resp.StatusCode, m
	}
	code, m := post("ldi r1, 5\nhalt")
	if code != 200 || m["size"].(float64) != 8 || m["fits"] != true {
		t.Fatalf("assemble ok case: %d %v", code, m)
	}
	if raw, _ := base64.StdEncoding.DecodeString(m["program"].(string)); len(raw) != 8 {
		t.Fatalf("program bytes = %d", len(raw))
	}
	code, m = post("ldi r1, 5\nbogus r1")
	if code != 400 || !strings.Contains(m["error"].(string), "line 2") {
		t.Fatalf("assemble error case: %d %v", code, m)
	}
	// Too big for the belt: assembles, but reports that it does not fit.
	code, m = post(strings.Repeat("nop\n", cfg.ProgramBytes/4+1))
	if code != 200 || m["fits"] != false {
		t.Fatalf("oversize case: %d %v", code, m)
	}
}

func TestWebAssets(t *testing.T) {
	srv, _ := newSite(t)
	for path, want := range map[string]string{
		"/":                    "<title>",
		"/manual.txt":          "PROGRAMMER'S REFERENCE MANUAL",
		"/examples/echo.s":     "ECHO",
		"/examples/index.json": `"pursue"`,
	} {
		resp, body := get(t, srv.URL+path)
		if resp.StatusCode != 200 || !strings.Contains(body, want) {
			t.Errorf("%s: status %d, missing %q", path, resp.StatusCode, want)
		}
	}
	resp, _ := get(t, srv.URL+"/")
	if !strings.Contains(resp.Header.Get("Content-Security-Policy"), "default-src 'self'") {
		t.Error("missing CSP header")
	}
	// The API still wins over the catch-all.
	if resp, _ := get(t, srv.URL+"/market"); !strings.HasPrefix(resp.Header.Get("Content-Type"), "application/json") {
		t.Errorf("/market served as %q", resp.Header.Get("Content-Type"))
	}
}