package v1

import (
	"bytes"
	"encoding/json"
	"fmt"
	"net/http"
	"net/http/httptest"
	"testing"
	"time"

	"github.com/gin-gonic/gin"
	"github.com/stretchr/testify/require"
	"gorm.io/datatypes"
	"gorm.io/driver/sqlite"
	"gorm.io/gorm"
	"gorm.io/gorm/logger"

	"github.com/gochat/gochat/internal/model"
	"github.com/gochat/gochat/internal/repository"
	"github.com/gochat/gochat/internal/service"
)

func TestEnterpriseAccountLimits_ChatwootPayload(t *testing.T) {
	router, db, account, user := setupEnterpriseAccountHandlerTest(t)

	account.AgentLimit = 3
	account.InboxLimit = 4
	account.Limits = datatypes.JSON(`{"captain_documents":5,"captain_responses":7}`)
	require.NoError(t, account.SetCustomAttributesMap(map[string]any{"captain_responses_usage": 2}))
	require.NoError(t, db.Save(account).Error)
	require.NoError(t, db.Create(&model.AccountUser{AccountID: account.ID, UserID: user.ID, Role: "administrator"}).Error)
	require.NoError(t, db.Create(&model.AccountUser{AccountID: account.ID, UserID: seedEnterpriseUser(t, db, "agent@example.com").ID, Role: "agent"}).Error)
	require.NoError(t, db.Create(&model.CaptainDocument{AccountID: account.ID, AssistantID: 1, Name: "Doc", ExternalLink: "https://example.com"}).Error)

	req := httptest.NewRequest(http.MethodGet, fmt.Sprintf("/enterprise/api/v1/accounts/%d/limits", account.ID), nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)

	require.Equal(t, http.StatusOK, w.Code, w.Body.String())
	var body map[string]any
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &body))
	require.Equal(t, float64(account.ID), body["id"])

	limits := body["limits"].(map[string]any)
	agents := limits["agents"].(map[string]any)
	require.Equal(t, float64(3), agents["allowed"])
	require.Equal(t, float64(2), agents["consumed"])

	captain := limits["captain"].(map[string]any)
	documents := captain["documents"].(map[string]any)
	require.Equal(t, float64(5), documents["total_count"])
	require.Equal(t, float64(4), documents["current_available"])
	require.Equal(t, float64(1), documents["consumed"])
	responses := captain["responses"].(map[string]any)
	require.Equal(t, float64(7), responses["total_count"])
	require.Equal(t, float64(5), responses["current_available"])
	require.Equal(t, float64(2), responses["consumed"])
}

func TestEnterpriseAccountLimits_CaptainUsageDoesNotExposeNegativeAvailability(t *testing.T) {
	router, db, account, user := setupEnterpriseAccountHandlerTest(t)

	account.Limits = datatypes.JSON(`{"captain_documents":1,"captain_responses":2}`)
	require.NoError(t, account.SetCustomAttributesMap(map[string]any{
		"captain_documents_usage": 3,
		"captain_responses_usage": 4,
	}))
	require.NoError(t, db.Save(account).Error)
	require.NoError(t, db.Create(&model.AccountUser{AccountID: account.ID, UserID: user.ID, Role: "administrator"}).Error)

	w := httptest.NewRecorder()
	req := httptest.NewRequest(http.MethodGet, fmt.Sprintf("/enterprise/api/v1/accounts/%d/limits", account.ID), nil)
	router.ServeHTTP(w, req)

	require.Equal(t, http.StatusOK, w.Code, w.Body.String())
	var body map[string]any
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &body))
	limits := body["limits"].(map[string]any)
	captain := limits["captain"].(map[string]any)
	documents := captain["documents"].(map[string]any)
	responses := captain["responses"].(map[string]any)
	require.Equal(t, float64(1), documents["total_count"])
	require.Equal(t, float64(3), documents["consumed"])
	require.Equal(t, float64(0), documents["current_available"])
	require.Equal(t, float64(2), responses["total_count"])
	require.Equal(t, float64(4), responses["consumed"])
	require.Equal(t, float64(0), responses["current_available"])
}

func TestEnterpriseAccountLimits_DefaultPlanPayload(t *testing.T) {
	router, db, account, user := setupEnterpriseAccountHandlerTest(t)
	require.NoError(t, account.SetCustomAttributesMap(map[string]any{"default_plan": true}))
	require.NoError(t, db.Save(account).Error)
	require.NoError(t, db.Create(&model.AccountUser{AccountID: account.ID, UserID: user.ID, Role: "administrator"}).Error)
	old := time.Now().AddDate(0, 0, -31)
	require.NoError(t, db.Create(&model.Conversation{AccountID: account.ID, InboxID: 1, ContactID: 1, ChannelType: "web_widget", Channel: "web_widget"}).Error)
	oldConversation := &model.Conversation{AccountID: account.ID, InboxID: 1, ContactID: 1, ChannelType: "web_widget", Channel: "web_widget"}
	oldConversation.CreatedAt = old
	require.NoError(t, db.Create(oldConversation).Error)
	require.NoError(t, db.Create(&model.Inbox{AccountID: account.ID, Name: "Web", ChannelType: "web_widget", ChannelID: 1}).Error)
	require.NoError(t, db.Create(&model.Inbox{AccountID: account.ID, Name: "Email", ChannelType: "email", ChannelID: 2}).Error)

	req := httptest.NewRequest(http.MethodGet, fmt.Sprintf("/enterprise/api/v1/accounts/%d/limits", account.ID), nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)

	require.Equal(t, http.StatusOK, w.Code, w.Body.String())
	var body map[string]any
	require.NoError(t, json.Unmarshal(w.Body.Bytes(), &body))
	limits := body["limits"].(map[string]any)
	conversation := limits["conversation"].(map[string]any)
	require.Equal(t, float64(500), conversation["allowed"])
	require.Equal(t, float64(1), conversation["consumed"])
	nonWeb := limits["non_web_inboxes"].(map[string]any)
	require.Equal(t, float64(0), nonWeb["allowed"])
	require.Equal(t, float64(1), nonWeb["consumed"])
}

func TestEnterpriseAccountLiteralFrontendPathsUseCurrentAccountContext(t *testing.T) {
	router, db, account, user := setupEnterpriseAccountHandlerTest(t)
	account.AgentLimit = 4
	account.Limits = datatypes.JSON(`{"captain_documents":3,"captain_responses":9}`)
	require.NoError(t, db.Save(account).Error)
	require.NoError(t, db.Create(&model.AccountUser{AccountID: account.ID, UserID: user.ID, Role: "administrator"}).Error)
	require.NoError(t, db.Create(&model.CaptainDocument{AccountID: account.ID, AssistantID: 1, Name: "Doc", ExternalLink: "https://example.com"}).Error)

	limits := httptest.NewRecorder()
	limitsReq := httptest.NewRequest(http.MethodGet, "/enterprise/api/v1/limits", nil)
	limitsReq.Header.Set("X-Account-ID", fmt.Sprint(account.ID))
	router.ServeHTTP(limits, limitsReq)
	require.Equal(t, http.StatusOK, limits.Code, limits.Body.String())
	var body map[string]any
	require.NoError(t, json.Unmarshal(limits.Body.Bytes(), &body))
	require.Equal(t, float64(account.ID), body["id"])
	limitPayload := body["limits"].(map[string]any)
	agents := limitPayload["agents"].(map[string]any)
	require.Equal(t, float64(4), agents["allowed"])
	require.Equal(t, float64(1), agents["consumed"])
	captain := limitPayload["captain"].(map[string]any)
	documents := captain["documents"].(map[string]any)
	require.Equal(t, float64(3), documents["total_count"])
	require.Equal(t, float64(1), documents["consumed"])
	require.Equal(t, float64(2), documents["current_available"])

	subscription := enterpriseAccountLiteralRequest(t, router, account.ID, http.MethodPost, "subscription", ``)
	require.Equal(t, http.StatusNoContent, subscription.Code, subscription.Body.String())
	require.NoError(t, db.First(account, account.ID).Error)
	require.Equal(t, true, account.CustomAttributesMap()["is_creating_customer"])

	checkout := enterpriseAccountLiteralRequest(t, router, account.ID, http.MethodPost, "checkout", ``)
	require.Equal(t, http.StatusUnprocessableEntity, checkout.Code, checkout.Body.String())
	require.Contains(t, checkout.Body.String(), "Please subscribe to a plan before viewing the billing details")

	topupMissingCredits := enterpriseAccountLiteralRequest(t, router, account.ID, http.MethodPost, "topup_checkout", `{}`)
	require.Equal(t, http.StatusUnprocessableEntity, topupMissingCredits.Code, topupMissingCredits.Body.String())
	require.Contains(t, topupMissingCredits.Body.String(), "Credits are required")

	deleteResp := enterpriseAccountLiteralRequest(t, router, account.ID, http.MethodPost, "toggle_deletion", `{"action_type":"delete"}`)
	require.Equal(t, http.StatusOK, deleteResp.Code, deleteResp.Body.String())
	require.NoError(t, db.First(account, account.ID).Error)
	require.Equal(t, "manual_deletion", account.CustomAttributesMap()["marked_for_deletion_reason"])
}

func TestEnterpriseAccountToggleDeletion(t *testing.T) {
	router, db, account, user := setupEnterpriseAccountHandlerTest(t)
	require.NoError(t, db.Create(&model.AccountUser{AccountID: account.ID, UserID: user.ID, Role: "administrator"}).Error)

	w := enterpriseAccountRequest(t, router, account.ID, http.MethodPost, "toggle_deletion", `{"action_type":"delete"}`)
	require.Equal(t, http.StatusOK, w.Code, w.Body.String())
	require.NoError(t, db.First(account, account.ID).Error)
	attrs := account.CustomAttributesMap()
	require.Equal(t, "manual_deletion", attrs["marked_for_deletion_reason"])
	require.NotEmpty(t, attrs["marked_for_deletion_at"])

	w = enterpriseAccountRequest(t, router, account.ID, http.MethodPost, "toggle_deletion", `{"action_type":"undelete"}`)
	require.Equal(t, http.StatusOK, w.Code, w.Body.String())
	require.NoError(t, db.First(account, account.ID).Error)
	attrs = account.CustomAttributesMap()
	require.NotContains(t, attrs, "marked_for_deletion_reason")
	require.NotContains(t, attrs, "marked_for_deletion_at")
}

func TestEnterpriseAccountBillingErrorBoundariesDoNotMutateAccount(t *testing.T) {
	router, db, account, user := setupEnterpriseAccountHandlerTest(t)
	require.NoError(t, db.Create(&model.AccountUser{AccountID: account.ID, UserID: user.ID, Role: "administrator"}).Error)
	require.NoError(t, account.SetCustomAttributesMap(map[string]any{"existing": "kept"}))
	require.NoError(t, db.Save(account).Error)

	checkout := enterpriseAccountRequest(t, router, account.ID, http.MethodPost, "checkout", ``)
	require.Equal(t, http.StatusUnprocessableEntity, checkout.Code, checkout.Body.String())
	var checkoutBody map[string]any
	require.NoError(t, json.Unmarshal(checkout.Body.Bytes(), &checkoutBody))
	require.Equal(t, "Please subscribe to a plan before viewing the billing details", checkoutBody["error"])

	missingCredits := enterpriseAccountRequest(t, router, account.ID, http.MethodPost, "topup_checkout", `{}`)
	require.Equal(t, http.StatusUnprocessableEntity, missingCredits.Code, missingCredits.Body.String())
	var missingCreditsBody map[string]any
	require.NoError(t, json.Unmarshal(missingCredits.Body.Bytes(), &missingCreditsBody))
	require.Equal(t, "Credits are required", missingCreditsBody["error"])

	providerUnavailable := enterpriseAccountRequest(t, router, account.ID, http.MethodPost, "topup_checkout", `{"credits":50}`)
	require.Equal(t, http.StatusUnprocessableEntity, providerUnavailable.Code, providerUnavailable.Body.String())
	var providerUnavailableBody map[string]any
	require.NoError(t, json.Unmarshal(providerUnavailable.Body.Bytes(), &providerUnavailableBody))
	require.Equal(t, "Top-up checkout provider is not configured", providerUnavailableBody["error"])

	invalidToggle := enterpriseAccountRequest(t, router, account.ID, http.MethodPost, "toggle_deletion", `{"action_type":"archive"}`)
	require.Equal(t, http.StatusUnprocessableEntity, invalidToggle.Code, invalidToggle.Body.String())
	var invalidToggleBody map[string]any
	require.NoError(t, json.Unmarshal(invalidToggle.Body.Bytes(), &invalidToggleBody))
	require.Equal(t, `Invalid action_type. Must be either "delete" or "undelete"`, invalidToggleBody["error"])

	require.NoError(t, db.First(account, account.ID).Error)
	attrs := account.CustomAttributesMap()
	require.Equal(t, "kept", attrs["existing"])
	require.NotContains(t, attrs, "is_creating_customer")
	require.NotContains(t, attrs, "marked_for_deletion_reason")
	require.NotContains(t, attrs, "marked_for_deletion_at")
}

func TestEnterpriseAccountSubscriptionSetsCreationFlag(t *testing.T) {
	router, db, account, user := setupEnterpriseAccountHandlerTest(t)
	require.NoError(t, db.Create(&model.AccountUser{AccountID: account.ID, UserID: user.ID, Role: "administrator"}).Error)

	w := enterpriseAccountRequest(t, router, account.ID, http.MethodPost, "subscription", ``)
	require.Equal(t, http.StatusNoContent, w.Code, w.Body.String())
	require.NoError(t, db.First(account, account.ID).Error)
	require.Equal(t, true, account.CustomAttributesMap()["is_creating_customer"])
}

func TestEnterpriseAccountSubscriptionPreservesExistingCustomerState(t *testing.T) {
	router, db, account, user := setupEnterpriseAccountHandlerTest(t)
	require.NoError(t, db.Create(&model.AccountUser{AccountID: account.ID, UserID: user.ID, Role: "administrator"}).Error)
	require.NoError(t, account.SetCustomAttributesMap(map[string]any{
		"stripe_customer_id": "cus_existing",
		"existing":           "kept",
	}))
	require.NoError(t, db.Save(account).Error)

	w := enterpriseAccountRequest(t, router, account.ID, http.MethodPost, "subscription", ``)
	require.Equal(t, http.StatusNoContent, w.Code, w.Body.String())
	require.NoError(t, db.First(account, account.ID).Error)
	attrs := account.CustomAttributesMap()
	require.Equal(t, "cus_existing", attrs["stripe_customer_id"])
	require.Equal(t, "kept", attrs["existing"])
	require.NotContains(t, attrs, "is_creating_customer")
}

func TestEnterpriseAccountRejectsAccountOutsideCurrentUser(t *testing.T) {
	router, _, account, _ := setupEnterpriseAccountHandlerTest(t)

	req := httptest.NewRequest(http.MethodGet, fmt.Sprintf("/enterprise/api/v1/accounts/%d/limits", account.ID), nil)
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)

	require.Equal(t, http.StatusNotFound, w.Code, w.Body.String())
}

func setupEnterpriseAccountHandlerTest(t *testing.T) (*gin.Engine, *gorm.DB, *model.Account, *model.User) {
	t.Helper()
	gin.SetMode(gin.TestMode)
	db, err := gorm.Open(sqlite.Open(":memory:"), &gorm.Config{Logger: logger.Default.LogMode(logger.Silent)})
	require.NoError(t, err)
	t.Cleanup(func() {
		sqlDB, _ := db.DB()
		_ = sqlDB.Close()
	})
	require.NoError(t, db.AutoMigrate(&model.Account{}, &model.User{}, &model.AccountUser{}, &model.Conversation{}, &model.Inbox{}, &model.CaptainDocument{}))

	user := seedEnterpriseUser(t, db, "admin@example.com")
	account := &model.Account{Name: "Acme", Active: true, Status: "active", Locale: "en"}
	require.NoError(t, db.Create(account).Error)

	svc := service.NewAccountService(repository.NewAccountRepo(db))
	handler := NewEnterpriseAccountHandler(svc)
	router := gin.New()
	router.Use(func(c *gin.Context) {
		c.Set("user_id", user.ID)
		c.Next()
	})
	accounts := router.Group("/enterprise/api/v1/accounts")
	accounts.GET("/:account_id/limits", handler.Limits)
	accounts.POST("/:account_id/toggle_deletion", handler.ToggleDeletion)
	accounts.POST("/:account_id/subscription", handler.Subscription)
	accounts.POST("/:account_id/checkout", handler.Checkout)
	accounts.POST("/:account_id/topup_checkout", handler.TopupCheckout)
	router.GET("/enterprise/api/v1/limits", handler.Limits)
	router.POST("/enterprise/api/v1/subscription", handler.Subscription)
	router.POST("/enterprise/api/v1/checkout", handler.Checkout)
	router.POST("/enterprise/api/v1/topup_checkout", handler.TopupCheckout)
	router.POST("/enterprise/api/v1/toggle_deletion", handler.ToggleDeletion)
	return router, db, account, user
}

func seedEnterpriseUser(t *testing.T, db *gorm.DB, email string) *model.User {
	t.Helper()
	user := &model.User{Name: email, Email: email, Password: "hashed", Active: true}
	require.NoError(t, db.Create(user).Error)
	return user
}

func enterpriseAccountRequest(t *testing.T, router *gin.Engine, accountID uint, method, action, body string) *httptest.ResponseRecorder {
	t.Helper()
	req := httptest.NewRequest(method, fmt.Sprintf("/enterprise/api/v1/accounts/%d/%s", accountID, action), bytes.NewBufferString(body))
	req.Header.Set("Content-Type", "application/json")
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	return w
}

func enterpriseAccountLiteralRequest(t *testing.T, router *gin.Engine, accountID uint, method, action, body string) *httptest.ResponseRecorder {
	t.Helper()
	req := httptest.NewRequest(method, fmt.Sprintf("/enterprise/api/v1/%s", action), bytes.NewBufferString(body))
	req.Header.Set("Content-Type", "application/json")
	req.Header.Set("X-Account-ID", fmt.Sprint(accountID))
	w := httptest.NewRecorder()
	router.ServeHTTP(w, req)
	return w
}