package httpapi

import (
	"errors"
	"net/http"
	"strings"
	"time"

	"data-terminal-cloud/internal/concurrency"
	"data-terminal-cloud/internal/hardwarelicense"
)

func ListOpsHardwareLicensesHandler(service *hardwarelicense.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		principal, tenantID, ok := opsDevicePrincipal(w, r)
		if !ok {
			return
		}
		items, err := service.List(r.Context(), principal, tenantID)
		if err != nil {
			writeHardwareLicenseError(w, r, err)
			return
		}
		w.Header().Set("Cache-Control", "no-store")
		WriteJSON(w, r, http.StatusOK, map[string]any{"items": items})
	})
}

func ImportOpsHardwareLicenseHandler(service *hardwarelicense.Service) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		principal, tenantID, ok := opsDevicePrincipal(w, r)
		if !ok {
			return
		}
		var body struct {
			LicenseRef string    `json:"license_ref"`
			License    string    `json:"license"`
			InstanceID string    `json:"instance_id"`
			ProductKey string    `json:"product_key"`
			ExpiresAt  time.Time `json:"expires_at"`
		}
		if !decodeWebJSON(w, r, &body, "License导入参数不正确") {
			return
		}
		item, err := service.Import(r.Context(), principal, tenantID, RequestID(r.Context()), hardwarelicense.ImportInput{LicenseRef: body.LicenseRef, Payload: body.License, InstanceID: body.InstanceID, ProductKey: body.ProductKey, ExpiresAt: body.ExpiresAt})
		if err != nil {
			writeHardwareLicenseError(w, r, err)
			return
		}
		w.Header().Set("Cache-Control", "no-store")
		w.Header().Set("ETag", concurrency.FormatETag(item.Version))
		WriteJSON(w, r, http.StatusCreated, item)
	})
}

func TransitionOpsHardwareLicenseHandler(service *hardwarelicense.Service, action string) http.Handler {
	return http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		principal, tenantID, ok := opsDevicePrincipal(w, r)
		if !ok {
			return
		}
		if !validUUID(r.PathValue("id")) {
			writeValidation(w, r, "License编号不正确", FieldError{Field: "id", Message: "必须是UUID"})
			return
		}
		expected, err := concurrency.ParseIfMatch(r)
		if err != nil {
			writeETagError(w, r, err)
			return
		}
		var item hardwarelicense.Item
		if action == "release" {
			item, err = service.Release(r.Context(), principal, tenantID, r.PathValue("id"), RequestID(r.Context()), expected)
		} else {
			item, err = service.Revoke(r.Context(), principal, tenantID, r.PathValue("id"), RequestID(r.Context()), expected)
		}
		if err != nil {
			writeHardwareLicenseError(w, r, err)
			return
		}
		w.Header().Set("Cache-Control", "no-store")
		w.Header().Set("ETag", concurrency.FormatETag(item.Version))
		WriteJSON(w, r, http.StatusOK, item)
	})
}

func writeHardwareLicenseError(w http.ResponseWriter, r *http.Request, err error) {
	switch {
	case errors.Is(err, hardwarelicense.ErrInvalid):
		writeValidation(w, r, "License参数不正确", FieldError{Field: "license", Message: "引用、密文、产品或到期时间不正确"})
	case errors.Is(err, hardwarelicense.ErrAccessDenied):
		WriteError(w, r, http.StatusForbidden, "OPS_ACCESS_DENIED", "仅独立运维账号可以管理License")
	case errors.Is(err, hardwarelicense.ErrNotFound):
		WriteError(w, r, http.StatusNotFound, "RESOURCE_NOT_FOUND", "License不存在")
	case errors.Is(err, hardwarelicense.ErrVersionConflict):
		WriteError(w, r, http.StatusPreconditionFailed, "VERSION_CONFLICT", "License信息已变化，请刷新后重试")
	case errors.Is(err, hardwarelicense.ErrAssignment):
		WriteError(w, r, http.StatusConflict, "HARDWARE_LICENSE_STATE_CONFLICT", "License当前状态不允许执行该操作")
	default:
		if strings.Contains(strings.ToLower(err.Error()), "duplicate") {
			WriteError(w, r, http.StatusConflict, "HARDWARE_LICENSE_ALREADY_EXISTS", "License引用已经存在")
			return
		}
		WriteError(w, r, http.StatusInternalServerError, "INTERNAL_ERROR", "License管理操作失败")
	}
}