package resources

import (
	"context"
	"fmt"

	"github.com/hashicorp/terraform-plugin-framework/path"
	"github.com/hashicorp/terraform-plugin-framework/resource"
	"github.com/hashicorp/terraform-plugin-framework/resource/schema"
	"github.com/hashicorp/terraform-plugin-framework/resource/schema/booldefault"
	"github.com/hashicorp/terraform-plugin-framework/types"
	"k8s.io/apimachinery/pkg/apis/meta/v1/unstructured"

	"terraform-provider-fission/internal/client"
)

var _ resource.Resource = &HTTPTriggerResource{}
var _ resource.ResourceWithImportState = &HTTPTriggerResource{}

// Изменено: 2026-04-14 20:15 UTC.
// Resource для управления Fission HTTPTrigger через Kubernetes CRD API.
type HTTPTriggerResource struct {
	client *client.Client
}

// httpTriggerResourceModel описывает состояние terraform ресурса fission_http_trigger.
type httpTriggerResourceModel struct {
	ID            types.String `tfsdk:"id"`
	Name          types.String `tfsdk:"name"`
	Function      types.String `tfsdk:"function"`
	URL           types.String `tfsdk:"url"`
	Methods       types.List   `tfsdk:"methods"`
	CreateIngress types.Bool   `tfsdk:"create_ingress"`
	Host          types.String `tfsdk:"host"`
	Namespace     types.String `tfsdk:"namespace"`
	UID           types.String `tfsdk:"uid"`
}

// NewHTTPTriggerResource создает инстанс ресурса HTTP trigger.
func NewHTTPTriggerResource() resource.Resource {
	return &HTTPTriggerResource{}
}

// Metadata задает имя ресурса fission_http_trigger.
func (r *HTTPTriggerResource) Metadata(_ context.Context, req resource.MetadataRequest, resp *resource.MetadataResponse) {
	resp.TypeName = req.ProviderTypeName + "_http_trigger"
}

// Schema задает Terraform schema для HTTPTrigger.
func (r *HTTPTriggerResource) Schema(_ context.Context, _ resource.SchemaRequest, resp *resource.SchemaResponse) {
	resp.Schema = schema.Schema{
		Attributes: map[string]schema.Attribute{
			"id": schema.StringAttribute{
				Computed:    true,
				Description: "Идентификатор ресурса (namespace/name).",
			},
			"name": schema.StringAttribute{
				Required:    true,
				Description: "Имя Fission HTTPTrigger.",
			},
			"function": schema.StringAttribute{
				Required:    true,
				Description: "Имя Fission Function, к которой привязан trigger.",
			},
			"url": schema.StringAttribute{
				Required:    true,
				Description: "Относительный URL, например /hello.",
			},
			"methods": schema.ListAttribute{
				Optional:    true,
				Computed:    true,
				ElementType: types.StringType,
				Description: "HTTP методы trigger, например [\"GET\", \"POST\"].",
			},
			"create_ingress": schema.BoolAttribute{
				Optional:    true,
				Computed:    true,
				Default:     booldefault.StaticBool(false),
				Description: "Включает создание ingress правила в Fission.",
			},
			"host": schema.StringAttribute{
				Optional:    true,
				Description: "Host для ingressconfig.host при create_ingress=true.",
			},
			"namespace": schema.StringAttribute{
				Optional:    true,
				Computed:    true,
				Description: "Namespace, где создается HTTPTrigger. По умолчанию используется provider namespace.",
			},
			"uid": schema.StringAttribute{
				Computed:    true,
				Description: "UID Kubernetes объекта HTTPTrigger.",
			},
		},
	}
}

// Configure получает клиент из provider.Configure().
func (r *HTTPTriggerResource) Configure(_ context.Context, req resource.ConfigureRequest, resp *resource.ConfigureResponse) {
	if req.ProviderData == nil {
		return
	}

	fissionClient, ok := req.ProviderData.(*client.Client)
	if !ok {
		resp.Diagnostics.AddError(
			"Некорректный тип provider data",
			fmt.Sprintf("Ожидался *client.Client, получен: %T", req.ProviderData),
		)
		return
	}

	r.client = fissionClient
}

// Create создает новый HTTPTrigger CRD объект.
func (r *HTTPTriggerResource) Create(ctx context.Context, req resource.CreateRequest, resp *resource.CreateResponse) {
	var plan httpTriggerResourceModel
	resp.Diagnostics.Append(req.Plan.Get(ctx, &plan)...)
	if resp.Diagnostics.HasError() {
		return
	}

	namespace := resolveNamespace(plan.Namespace, r.client.Namespace)
	triggerObject, err := httpTriggerToUnstructured(ctx, plan, namespace)
	if err != nil {
		resp.Diagnostics.AddError("Ошибка подготовки HTTPTrigger", err.Error())
		return
	}

	createdTrigger, err := r.client.CreateHTTPTrigger(ctx, triggerObject)
	if err != nil {
		resp.Diagnostics.AddError("Ошибка создания Fission HTTPTrigger", err.Error())
		return
	}

	state := unstructuredToHTTPTriggerModel(ctx, createdTrigger, plan)
	resp.Diagnostics.Append(resp.State.Set(ctx, &state)...)
}

// Read синхронизирует Terraform state с текущим состоянием HTTPTrigger CRD.
func (r *HTTPTriggerResource) Read(ctx context.Context, req resource.ReadRequest, resp *resource.ReadResponse) {
	var state httpTriggerResourceModel
	resp.Diagnostics.Append(req.State.Get(ctx, &state)...)
	if resp.Diagnostics.HasError() {
		return
	}

	namespace := resolveNamespace(state.Namespace, r.client.Namespace)
	triggerObject, err := r.client.GetHTTPTrigger(ctx, namespace, state.Name.ValueString())
	if err != nil {
		if client.IsNotFound(err) {
			resp.State.RemoveResource(ctx)
			return
		}

		resp.Diagnostics.AddError("Ошибка чтения Fission HTTPTrigger", err.Error())
		return
	}

	updatedState := unstructuredToHTTPTriggerModel(ctx, triggerObject, state)
	resp.Diagnostics.Append(resp.State.Set(ctx, &updatedState)...)
}

// Update обновляет существующий HTTPTrigger CRD объект.
func (r *HTTPTriggerResource) Update(ctx context.Context, req resource.UpdateRequest, resp *resource.UpdateResponse) {
	var plan httpTriggerResourceModel
	resp.Diagnostics.Append(req.Plan.Get(ctx, &plan)...)
	if resp.Diagnostics.HasError() {
		return
	}

	namespace := resolveNamespace(plan.Namespace, r.client.Namespace)
	existingTrigger, err := r.client.GetHTTPTrigger(ctx, namespace, plan.Name.ValueString())
	if err != nil {
		resp.Diagnostics.AddError("Ошибка получения HTTPTrigger перед обновлением", err.Error())
		return
	}

	triggerObject, err := httpTriggerToUnstructured(ctx, plan, namespace)
	if err != nil {
		resp.Diagnostics.AddError("Ошибка подготовки HTTPTrigger", err.Error())
		return
	}
	triggerObject.SetResourceVersion(existingTrigger.GetResourceVersion())

	updatedTrigger, err := r.client.UpdateHTTPTrigger(ctx, triggerObject)
	if err != nil {
		resp.Diagnostics.AddError("Ошибка обновления Fission HTTPTrigger", err.Error())
		return
	}

	state := unstructuredToHTTPTriggerModel(ctx, updatedTrigger, plan)
	resp.Diagnostics.Append(resp.State.Set(ctx, &state)...)
}

// Delete удаляет HTTPTrigger CRD объект.
func (r *HTTPTriggerResource) Delete(ctx context.Context, req resource.DeleteRequest, resp *resource.DeleteResponse) {
	var state httpTriggerResourceModel
	resp.Diagnostics.Append(req.State.Get(ctx, &state)...)
	if resp.Diagnostics.HasError() {
		return
	}

	namespace := resolveNamespace(state.Namespace, r.client.Namespace)
	err := r.client.DeleteHTTPTrigger(ctx, namespace, state.Name.ValueString())
	if err != nil && !client.IsNotFound(err) {
		resp.Diagnostics.AddError("Ошибка удаления Fission HTTPTrigger", err.Error())
	}
}

// ImportState поддерживает импорт ресурса в формате namespace/name.
func (r *HTTPTriggerResource) ImportState(ctx context.Context, req resource.ImportStateRequest, resp *resource.ImportStateResponse) {
	namespace, name, err := parseImportID(req.ID)
	if err != nil {
		resp.Diagnostics.AddError("Некорректный формат import ID", err.Error())
		return
	}

	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("id"), req.ID)...)
	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("namespace"), namespace)...)
	resp.Diagnostics.Append(resp.State.SetAttribute(ctx, path.Root("name"), name)...)
}

// httpTriggerToUnstructured преобразует Terraform model в Kubernetes CRD payload.
func httpTriggerToUnstructured(ctx context.Context, model httpTriggerResourceModel, namespace string) (*unstructured.Unstructured, error) {
	methods := []string{"GET"}
	if !model.Methods.IsNull() && !model.Methods.IsUnknown() {
		if len(model.Methods.Elements()) > 0 {
			methods = []string{}
			var methodValues []string
			diags := model.Methods.ElementsAs(ctx, &methodValues, false)
			if diags.HasError() {
				return nil, fmt.Errorf("convert methods list")
			}
			methods = append(methods, methodValues...)
		}
	}

	createIngress := false
	if !model.CreateIngress.IsNull() && !model.CreateIngress.IsUnknown() {
		createIngress = model.CreateIngress.ValueBool()
	}

	object := map[string]interface{}{
		"apiVersion": "fission.io/v1",
		"kind":       "HTTPTrigger",
		"metadata": map[string]interface{}{
			"name":      model.Name.ValueString(),
			"namespace": namespace,
		},
		"spec": map[string]interface{}{
			"relativeurl": model.URL.ValueString(),
			"methods":     methods,
			"functionref": map[string]interface{}{
				"type": "name",
				"name": model.Function.ValueString(),
			},
			"createingress": createIngress,
		},
	}

	host := model.Host.ValueString()
	if host != "" {
		_ = unstructured.SetNestedField(object, map[string]interface{}{"host": host}, "spec", "ingressconfig")
	}

	return &unstructured.Unstructured{Object: object}, nil
}

// unstructuredToHTTPTriggerModel читает нужные поля из CRD объекта обратно в Terraform state.
func unstructuredToHTTPTriggerModel(ctx context.Context, triggerObject *unstructured.Unstructured, base httpTriggerResourceModel) httpTriggerResourceModel {
	urlValue, _, _ := unstructured.NestedString(triggerObject.Object, "spec", "relativeurl")
	functionName, _, _ := unstructured.NestedString(triggerObject.Object, "spec", "functionref", "name")
	hostValue, _, _ := unstructured.NestedString(triggerObject.Object, "spec", "ingressconfig", "host")
	createIngressValue, foundCreateIngress, _ := unstructured.NestedBool(triggerObject.Object, "spec", "createingress")
	methodsValue, _, _ := unstructured.NestedStringSlice(triggerObject.Object, "spec", "methods")

	methodsList, _ := types.ListValueFrom(ctx, types.StringType, methodsValue)

	state := base
	state.Name = types.StringValue(triggerObject.GetName())
	state.Namespace = types.StringValue(triggerObject.GetNamespace())
	state.ID = types.StringValue(fmt.Sprintf("%s/%s", triggerObject.GetNamespace(), triggerObject.GetName()))
	state.UID = types.StringValue(string(triggerObject.GetUID()))
	state.Methods = methodsList

	if urlValue != "" {
		state.URL = types.StringValue(urlValue)
	}
	if functionName != "" {
		state.Function = types.StringValue(functionName)
	}
	if hostValue != "" {
		state.Host = types.StringValue(hostValue)
	}
	if foundCreateIngress {
		state.CreateIngress = types.BoolValue(createIngressValue)
	}

	return state
}