Move intern functions into prelude lib to avoid cyclic imports

Signed-off-by: Nicolas Paul <n@nc0.fr>

1 files changed, 93 insertions, 0 deletions

diff --git a/pkg/config/lib/prelude/prelude.go b/pkg/config/lib/prelude/prelude.go
new file mode 100644
index 0000000..c1e42f4
--- /dev/null
+++ b/pkg/config/lib/prelude/prelude.go
@@ -0,0 +1,93 @@
+package prelude
+
+import (
+	"fmt"
+	"go.nc0.fr/svgu/pkg/types"
+	"go.starlark.net/starlark"
+	"strings"
+)
+
+// https://stackoverflow.com/questions/1976007/what-characters-are-forbidden-in-windows-and-linux-directory-names
+const invalidName string = "..\\/<>:\"|?* \t\n\r\b\findex"
+
+// Registered represents the index of registered modules.
+var Registered types.Index
+
+// InternIndex represents the built-in function "index".
+// index(domain) initializes a new index with the given domain.
+func InternIndex(_ *starlark.Thread, _ *starlark.Builtin, args starlark.Tuple,
+	kwargs []starlark.Tuple) (starlark.Value, error) {
+	var domain string
+	if err := starlark.UnpackArgs("index", args, kwargs,
+		"domain", &domain); err != nil {
+		return nil, err
+	}
+
+	Registered.SetDomain(domain)
+
+	return starlark.None, nil
+}
+
+// InternModule represents the built-in function "module".
+// module(name, vcs, repo, dir, file) registers a new module into the
+// index.
+func InternModule(_ *starlark.Thread, _ *starlark.Builtin, args starlark.Tuple,
+	kwargs []starlark.Tuple) (starlark.Value, error) {
+
+	var name, vcs, repo, dir, file string
+	if err := starlark.UnpackArgs("module", args, kwargs, "name",
+		&name, "vcs", &vcs, "repo", &repo, "dir", &dir, "file", &file); err != nil {
+		return nil, err
+	}
+
+	if Registered.Domain == "" {
+		return nil, fmt.Errorf("index not initialized")
+	}
+
+	if name == "" {
+		return nil, fmt.Errorf("module name cannot be empty")
+	}
+
+	if vcs == "" {
+		return nil, fmt.Errorf("module %q vcs cannot be empty", name)
+	}
+
+	if repo == "" {
+		return nil, fmt.Errorf("module %q repo cannot be empty", name)
+	}
+
+	// Check for name conditions.
+	if strings.Contains(invalidName, name) {
+		return nil, fmt.Errorf("module %q name is invalid", name)
+	}
+
+	if Registered.CheckModule(name) {
+		return nil, fmt.Errorf("module %q already exists", name)
+	}
+
+	var v types.Vcs
+	switch vcs {
+	case "git":
+		v = types.VcsGit
+	case "hg":
+		v = types.VcsMercurial
+	case "svn":
+		v = types.VcsSubversion
+	case "fossil":
+		v = types.VcsFossil
+	case "bzr":
+		v = types.VcsBazaar
+	default:
+		return nil, fmt.Errorf("unknown vcs %q", vcs)
+	}
+
+	Registered.AddModule(name, types.Module{
+		Path: name,
+		Vcs:  v,
+		Repo: repo,
+		Dir:  dir,
+		File: file,
+	})
+
+	return starlark.None, nil
+}