package vip

import (
	"encoding/json"
	"testing"
	"time"

	"chatapp3-golang/internal/model"
)

func TestBuildPurchasePlanNewPurchase(t *testing.T) {
	now := time.Date(2026, 4, 29, 10, 0, 0, 0, time.UTC)
	configs := vipTestConfigs()

	plan, err := buildPurchasePlan(now, nil, configs[2], configs)
	if err != nil {
		t.Fatalf("buildPurchasePlan returned error: %v", err)
	}

	if plan.OrderType != orderTypePurchase {
		t.Fatalf("order type = %s, want %s", plan.OrderType, orderTypePurchase)
	}
	if plan.CurrentLevel != 0 || plan.TargetLevel != 2 {
		t.Fatalf("levels = %d -> %d, want 0 -> 2", plan.CurrentLevel, plan.TargetLevel)
	}
	if plan.PayableGold != 2000 {
		t.Fatalf("payable = %d, want 2000", plan.PayableGold)
	}
	if !plan.StartAt.Equal(now) || !plan.ExpireAt.Equal(now.AddDate(0, 0, vipDurationDay)) {
		t.Fatalf("period = %s -> %s, want %s -> %s", plan.StartAt, plan.ExpireAt, now, now.AddDate(0, 0, vipDurationDay))
	}
}

func TestBuildPurchasePlanUpgradePaysDifferenceAndKeepsExpireAt(t *testing.T) {
	now := time.Date(2026, 4, 29, 10, 0, 0, 0, time.UTC)
	startAt := now.AddDate(0, 0, -5)
	expireAt := now.AddDate(0, 0, 25)
	configs := vipTestConfigs()
	state := &model.UserVipState{
		Level:    2,
		Status:   statusActive,
		StartAt:  startAt,
		ExpireAt: expireAt,
	}

	plan, err := buildPurchasePlan(now, state, configs[4], configs)
	if err != nil {
		t.Fatalf("buildPurchasePlan returned error: %v", err)
	}

	if plan.OrderType != orderTypeUpgrade {
		t.Fatalf("order type = %s, want %s", plan.OrderType, orderTypeUpgrade)
	}
	if plan.PayableGold != 2000 {
		t.Fatalf("payable = %d, want 2000", plan.PayableGold)
	}
	if !plan.StartAt.Equal(startAt) || !plan.ExpireAt.Equal(expireAt) {
		t.Fatalf("upgrade period changed to %s -> %s, want %s -> %s", plan.StartAt, plan.ExpireAt, startAt, expireAt)
	}
}

func TestBuildPurchasePlanRenewExtendsThirtyDays(t *testing.T) {
	now := time.Date(2026, 4, 29, 10, 0, 0, 0, time.UTC)
	startAt := now.AddDate(0, 0, -5)
	expireAt := now.AddDate(0, 0, 25)
	configs := vipTestConfigs()
	state := &model.UserVipState{
		Level:    3,
		Status:   statusActive,
		StartAt:  startAt,
		ExpireAt: expireAt,
	}

	plan, err := buildPurchasePlan(now, state, configs[3], configs)
	if err != nil {
		t.Fatalf("buildPurchasePlan returned error: %v", err)
	}

	if plan.OrderType != orderTypeRenew {
		t.Fatalf("order type = %s, want %s", plan.OrderType, orderTypeRenew)
	}
	if plan.PayableGold != 3000 {
		t.Fatalf("payable = %d, want 3000", plan.PayableGold)
	}
	if !plan.ExpireAt.Equal(expireAt.AddDate(0, 0, vipDurationDay)) {
		t.Fatalf("renew expireAt = %s, want %s", plan.ExpireAt, expireAt.AddDate(0, 0, vipDurationDay))
	}
}

func TestBuildPurchasePlanRejectsDowngrade(t *testing.T) {
	now := time.Date(2026, 4, 29, 10, 0, 0, 0, time.UTC)
	configs := vipTestConfigs()
	state := &model.UserVipState{
		Level:    4,
		Status:   statusActive,
		StartAt:  now.AddDate(0, 0, -5),
		ExpireAt: now.AddDate(0, 0, 25),
	}

	if _, err := buildPurchasePlan(now, state, configs[2], configs); err == nil {
		t.Fatal("buildPurchasePlan returned nil error for downgrade")
	}
}

func TestVipResourcePayloadAcceptsStringResourceID(t *testing.T) {
	var payload VipResourcePayload
	if err := json.Unmarshal([]byte(`{"resourceId":"2045029471274201089","name":"vip","url":"https://example.com/a.svga"}`), &payload); err != nil {
		t.Fatalf("unmarshal resource payload: %v", err)
	}
	if payload.ResourceID.Int64() != 2045029471274201089 {
		t.Fatalf("resource id = %d, want 2045029471274201089", payload.ResourceID.Int64())
	}

	body, err := json.Marshal(payload)
	if err != nil {
		t.Fatalf("marshal resource payload: %v", err)
	}
	if got := string(body); got != `{"resourceId":"2045029471274201089","name":"vip","url":"https://example.com/a.svga"}` {
		t.Fatalf("json = %s", got)
	}
}

func vipTestConfigs() map[int]model.VipLevelConfig {
	configs := make(map[int]model.VipLevelConfig, levelCount)
	for level := 1; level <= levelCount; level++ {
		configs[level] = model.VipLevelConfig{
			Level:        level,
			LevelCode:    levelCode(level),
			DisplayName:  levelDisplayName(level),
			Enabled:      true,
			DurationDays: vipDurationDay,
			PriceGold:    int64(level * 1000),
		}
	}
	return configs
}