package main

import (
	"bytes"
	"os"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
)

func TestHandleIndexRendersWatts(t *testing.T) {
	srv := &server{secret: "secret", store: &store{value: 123}}
	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()

	srv.handleIndex(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want %d", rec.Code, http.StatusOK)
	}
	if !strings.Contains(rec.Body.String(), "123") {
		t.Fatalf("response did not contain watt value: %s", rec.Body.String())
	}
}

func TestHandleWriteRequiresSecret(t *testing.T) {
	srv := &server{secret: "secret", store: &store{}}
	req := httptest.NewRequest(http.MethodPost, "/write", bytes.NewBufferString(`{"watts":456}`))
	req.Header.Set("Content-Type", "application/json")
	rec := httptest.NewRecorder()

	srv.handleWrite(rec, req)

	if rec.Code != http.StatusUnauthorized {
		t.Fatalf("status = %d, want %d", rec.Code, http.StatusUnauthorized)
	}
}

func TestHandleWriteStoresValue(t *testing.T) {
	srv := &server{secret: "secret", store: &store{}}
	req := httptest.NewRequest(http.MethodPost, "/write", bytes.NewBufferString(`{"watts":456}`))
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("X-Secret", "secret")
	rec := httptest.NewRecorder()

	srv.handleWrite(rec, req)

	if rec.Code != http.StatusOK {
		t.Fatalf("status = %d, want %d", rec.Code, http.StatusOK)
	}
	if got := srv.store.get(); got != 456 {
		t.Fatalf("stored watts = %d, want %d", got, 456)
	}
}

func TestLoadConfig(t *testing.T) {
	path := t.TempDir() + "/config.json"
	if err := os.WriteFile(path, []byte(`{"write_secret":"secret","addr":":9090"}`), 0o600); err != nil {
		t.Fatalf("write config: %v", err)
	}

	cfg, err := loadConfig(path)
	if err != nil {
		t.Fatalf("loadConfig returned error: %v", err)
	}
	if cfg.WriteSecret != "secret" {
		t.Fatalf("write_secret = %q, want %q", cfg.WriteSecret, "secret")
	}
	if cfg.Addr != ":9090" {
		t.Fatalf("addr = %q, want %q", cfg.Addr, ":9090")
	}
}