package platform

import (
	"net/http"

	"github.com/gin-gonic/gin"
)

// ResourceMode describes the operations a platform-admin resource supports.
type ResourceMode string

const (
	Writable   ResourceMode = "writable"
	ReadOnly   ResourceMode = "readonly"
	AppendOnly ResourceMode = "append_only"
)

// ResourceContract is the expected cross-layer representation of one resource.
type ResourceContract struct {
	Domain   string
	Name     string
	Path     string
	PageKind string
	Mode     ResourceMode
}

// ResourceDefinition describes a route resource and the fields it may change.
type ResourceDefinition struct {
	Domain       string
	Name         string
	Model        func() any
	Mode         ResourceMode
	CreateFields []string
	UpdateFields []string
}

// Allows reports whether a resource mode supports an HTTP method.
func (d ResourceDefinition) Allows(method string) bool {
	switch d.Mode {
	case ReadOnly:
		return method == http.MethodGet
	case AppendOnly:
		return method == http.MethodGet || method == http.MethodPost
	case Writable:
		return method == http.MethodGet || method == http.MethodPost || method == http.MethodPut || method == http.MethodPatch || method == http.MethodDelete
	default:
		return false
	}
}

func archiveValues() gin.H {
	return gin.H{"status": "archived"}
}

func filterFields(values map[string]any, allowedFields []string) gin.H {
	allowed := make(map[string]struct{}, len(allowedFields))
	for _, field := range allowedFields {
		allowed[field] = struct{}{}
	}

	filtered := make(gin.H, len(allowed))
	for field, value := range values {
		if _, ok := allowed[field]; ok {
			filtered[field] = value
		}
	}
	return filtered
}

// ExpectedResources returns the complete platform-admin resource catalogue.
func ExpectedResources() []ResourceContract {
	return []ResourceContract{
		resourceContract("gas", "gas_basic", Writable, "list"), resourceContract("gas", "gas_account", Writable, "list"),
		resourceContract("delivery", "delivery_basic", Writable, "list"), resourceContract("delivery", "delivery_account", Writable, "list"),
		resourceContract("staff", "staff_account", Writable, "list"), resourceContract("staff", "staff_credential", Writable, "list"),
		resourceContract("user", "user_account", Writable, "list"), resourceContract("user", "user_address", Writable, "list"), resourceContract("user", "user_service_relation", Writable, "list"),
		resourceContract("device", "dev_smart_cylinder_valve", Writable, "list"), resourceContract("device", "dev_device_binding", Writable, "list"), resourceContract("device", "dev_telemetry", ReadOnly, "list"),
		resourceContract("safety", "safe_rule", Writable, "list"), resourceContract("safety", "safe_event", Writable, "list"), resourceContract("safety", "safe_inspection", Writable, "list"), resourceContract("safety", "safe_event_disposal", AppendOnly, "list"),
		resourceContract("ec", "ec_category", Writable, "list"), resourceContract("ec", "ec_product", Writable, "list"), resourceContract("ec", "ec_product_attribute", Writable, "list"), resourceContract("ec", "ec_product_image", Writable, "list"), resourceContract("ec", "ec_cart", Writable, "list"), resourceContract("ec", "ec_order", Writable, "list"), resourceContract("ec", "ec_order_item", Writable, "list"), resourceContract("ec", "ec_review", Writable, "list"),
		resourceContract("delivery", "delivery_task", Writable, "list"), resourceContract("delivery", "delivery_track", Writable, "list"), resourceContract("delivery", "delivery_track_point", ReadOnly, "list"),
		resourceContract("finance", "fin_payment", Writable, "list"), resourceContract("finance", "fin_settlement", Writable, "list"), resourceContract("finance", "fin_reconciliation", Writable, "list"),
		resourceContract("content", "cnt_content", Writable, "list"), resourceContract("notification", "ntf_template", Writable, "list"), resourceContract("customer_service", "cs_ticket", Writable, "list"),
		resourceContract("platform", "platfrom_account", Writable, "list"), resourceContract("platform", "platform_role", Writable, "list"), resourceContract("platform", "platform_menu", Writable, "tree"),
		resourceContract("wallet", "wallet", ReadOnly, "list"), resourceContract("wallet", "wallet_ledger", ReadOnly, "list"), resourceContract("wallet", "wallet_recharge", ReadOnly, "list"), resourceContract("wallet", "wallet_withdrawal", ReadOnly, "list"),
		resourceContract("report", "report", ReadOnly, "list"), resourceContract("report", "report_item", ReadOnly, "list"), resourceContract("report", "report_metric_snapshot", ReadOnly, "list"),
		resourceContract("audit", "audit_operation_log", ReadOnly, "list"), resourceContract("audit", "audit_export_log", ReadOnly, "list"), resourceContract("audit", "audit_approval", ReadOnly, "list"),
	}
}

func resourceContract(domain, name string, mode ResourceMode, pageKind string) ResourceContract {
	return ResourceContract{Domain: domain, Name: name, Path: resourcePath(domain, name), Mode: mode, PageKind: pageKind}
}

func resourcePath(domain, name string) string {
	switch name {
	case "staff_account":
		return "/staff/account"
	case "staff_credential":
		return "/staff/credential"
	case "user_account":
		return "/user/account"
	case "user_address":
		return "/user/address"
	case "user_service_relation":
		return "/user/service_relation"
	case "safe_event_disposal":
		return "/safety/safe_event/:identity/disposals"
	default:
		return "/" + domain + "/" + name
	}
}