package rpc

import (
	"errors"
	"fmt"
	"os"
	"strings"
)

var ErrApprovedWorkerRequired = errors.New("approved call worker is required")

// NewApprovedAgentServer binds the control RPC and one-shot originate callback
// to the same task-call registry. The separate legacy hooks are not accepted
// on either explicitly selected entry: otherwise a control could confirm while
// a call started by a different adapter remains active.
func NewApprovedAgentServer(options ServerOptions, worker *ApprovedCallWorker) (*Server, error) {
	if worker == nil {
		return nil, ErrApprovedWorkerRequired
	}
	if (options.Mode != "mock" && options.Mode != "nonprod-real") || options.StatePath == "" || options.Status == nil || options.Status.AgentId == "" || options.Status.CellId == "" || options.Status.BootId == "" || strings.TrimSpace(options.ApprovedDispatcherID) == "" || options.LoadedSIP == nil {
		return nil, errors.New("approved Agent requires an explicit supported mode, durable state, Agent and Dispatcher identity, and observed SIP")
	}
	if worker.Lifecycle == nil || worker.Calls == nil || worker.Prepare == nil || worker.OnFailure == nil {
		return nil, errors.New("approved Agent requires a process lifecycle, task calls, runner and failure reporting")
	}
	if _, err := os.Lstat(options.StatePath + ".executions"); err == nil {
		return nil, errors.New("legacy Agent execution state requires operator disposition")
	} else if !errors.Is(err, os.ErrNotExist) {
		return nil, fmt.Errorf("inspect legacy Agent execution state: %w", err)
	}
	if options.MockApprovedOriginate != nil || options.NonprodRealOriginate != nil || options.ApprovedTaskCalls != nil {
		return nil, errors.New("approved Agent cannot use competing call or control adapters")
	}
	// Copy the configuration so later mutation of worker fields cannot cause
	// ExecuteApproved and task controls to observe different registries.
	frozen := *worker
	if options.Mode == "mock" {
		options.MockApprovedOriginate = frozen.Originate
	} else {
		options.NonprodRealOriginate = frozen.Originate
	}
	options.ApprovedTaskCalls = frozen.Calls
	return NewServer(options), nil
}