package runtime

import (
	"github.com/novox/mesh-tools/node-tools/internal/approval"
	"github.com/novox/mesh-tools/node-tools/internal/launch"
)

// FingerprintWord is the word of a module's composed environment that names the build its bundle serves (design 47 G §424).
const FingerprintWord = "MESH_FINGERPRINT"

// Gate is the approval gate the runner serves through (design 46 7-approval-mark §4, §20; node-tools/internal/approval).
type Gate interface {
	// Unserved is, of a module's marked tools, those its bundle does not register, saying it as the module's finding.
	Unserved(module, fingerprint string, registered []string) []string
	// Run is a call through the gate: run is called only when the call may run now, once.
	Run(call approval.Call, run func() (any, error)) (any, error)
}

// gatedRun is how a handler calls a tool: through the gate where there is one.
type gatedRun func(call approval.Call, t launch.Tool, caller string) (any, error)

// gated calls the tool through the gate, or straight where the runner has none.
func (c *consumers) gated(call approval.Call, t launch.Tool, caller string) (any, error) {
	run := func() (any, error) { return t.Run(caller, call.Args) }
	if c.gate == nil {
		return run()
	}
	return c.gate.Run(call, run)
}

// WithGate serves every call through the approval gate.
func WithGate(g Gate) Option { return func(c *consumers) { c.gate = g } }

var _ Gate = (*approval.Gate)(nil)

// unservedMarks is, of the module's marked tools, those its bundle's registrations under its own name do not register.
func (r *runner) unservedMarks(module string, regs []launch.Registration) []string {
	if r.events.gate == nil {
		return nil
	}
	var registered []string
	for _, reg := range regs {
		if reg.Module == module {
			for _, t := range reg.Tools {
				registered = append(registered, t.Name)
			}
		}
	}
	return r.events.gate.Unserved(module, r.fingerprintOf(module), registered)
}