package main

import (
	"fmt"
	"io"
	"net/http"
	"net/http/httptest"
	"strings"
	"time"
)

// waktuDemo adalah waktu beku supaya output demo selalu identik.
var waktuDemo = time.Date(2026, 1, 15, 8, 0, 0, 0, time.UTC)

// demo menjalankan seluruh endpoint di atas MemoryItemRepository
// tanpa PostgreSQL dan tanpa membuka port. Setiap permintaan dikirim
// lewat httptest.NewRecorder, lalu status dan body dicetak. Gunakan
// `go run . demo` untuk mencoba API tanpa database.
func demo() {
	svc := NewItemService(NewMemoryItemRepository(), FixedClock{Waktu: waktuDemo})
	router := NewRouter(svc)

	fmt.Println("=== Demo REST API item (mode memori, tanpa PostgreSQL) ===")
	skenario := []struct {
		metode string
		target string
		body   string
	}{
		{"POST", "/items", `{"name":"Buku Go","price":75000}`},
		{"POST", "/items", `{"name":"Mouse","price":150000}`},
		{"POST", "/items", `{"name":"","price":-100}`},
		{"GET", "/items", ""},
		{"GET", "/items/1", ""},
		{"PUT", "/items/2", `{"name":"Mouse Nirkabel","price":175000}`},
		{"GET", "/items/999", ""},
		{"DELETE", "/items/1", ""},
		{"GET", "/items", ""},
	}
	for _, tt := range skenario {
		kirimDemo(router, tt.metode, tt.target, tt.body)
	}
}

// kirimDemo mengirim satu permintaan ke router lalu mencetak status,
// header Location, dan body respons.
func kirimDemo(router http.Handler, metode, target, body string) {
	var rdr io.Reader
	if body != "" {
		rdr = strings.NewReader(body)
	}
	req := httptest.NewRequest(metode, target, rdr)
	if body != "" {
		req.Header.Set("Content-Type", "application/json")
	}
	rec := httptest.NewRecorder()
	router.ServeHTTP(rec, req)

	fmt.Printf("%s %s → %d %s\n", metode, target, rec.Code, http.StatusText(rec.Code))
	if loc := rec.Header().Get("Location"); loc != "" {
		fmt.Printf("  Location: %s\n", loc)
	}
	if b := strings.TrimSpace(rec.Body.String()); b != "" {
		fmt.Printf("  body: %s\n", b)
	}
}