package allowlist

import (
	"context"
	"fmt"

	"git.d-ma.be/mathias/gitea-mcp/internal/gitea"
)

type Allowlist struct {
	owners map[string]struct{}
}

func New(owners []string) *Allowlist {
	m := make(map[string]struct{}, len(owners))
	for _, o := range owners {
		m[o] = struct{}{}
	}
	return &Allowlist{owners: m}
}

// Check gates owner access to the static list — except for a caller
// authenticated with their own Gitea PAT (pass-through, gitea-mcp#59), whose
// access Gitea's own permission model already gates more precisely than a
// coarse owner name list ever could.
func (a *Allowlist) Check(ctx context.Context, owner string) error {
	if owner == "" {
		return fmt.Errorf("owner required")
	}
	if _, ok := gitea.TokenFromContext(ctx); ok {
		return nil
	}
	if _, ok := a.owners[owner]; !ok {
		return fmt.Errorf("owner %q not in allowlist", owner)
	}
	return nil
}