package configkit_test

import (
	"os"
	"path/filepath"
	"testing"
	"testing/fstest"

	configkit "go.maximumdirect.net/configkit"
)

func TestMainRelativeCompanion(t *testing.T) {
	dir := t.TempDir()
	if err := os.WriteFile(filepath.Join(dir, "main.yml"), []byte("count: 3\n"), 0600); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(filepath.Join(dir, "extra.yml"), []byte("settings: {companion: host}\n"), 0600); err != nil {
		t.Fatal(err)
	}
	binding := configkit.MainRelative()
	companion := configkit.Input{Source: configkit.Bytes("companions", []byte("config: {imports: [{path: extra.yml}]}\n")), Imports: true, MainRelative: binding}
	result, err := configkit.LoadLayered(configkit.Input{Source: configkit.File(filepath.Join(dir, "main.yml"))}, configkit.LayeredOptions[layeredFacadeConfig]{Underlays: []configkit.Underlay{{Inputs: []configkit.Input{companion}}}})
	if err != nil {
		t.Fatalf("%v: %#v", err, err.(*configkit.LoadError).Diagnostics())
	}
	if result.Config.Count != 3 || result.Config.Settings["companion"] != "host" {
		t.Fatalf("configuration = %#v", result.Config)
	}
	native := configkit.NewFilesystem("bundle", fstest.MapFS{"dir/main.yml": &fstest.MapFile{Data: []byte("count: 4\n")}, "dir/extra.yml": &fstest.MapFile{Data: []byte("settings: {companion: native}\n")}})
	result, err = configkit.LoadLayered(configkit.Input{Source: native.File("dir/main.yml")}, configkit.LayeredOptions[layeredFacadeConfig]{Underlays: []configkit.Underlay{{Inputs: []configkit.Input{companion}}}})
	if err != nil {
		t.Fatalf("%v: %#v", err, err.(*configkit.LoadError).Diagnostics())
	}
	if result.Config.Count != 4 || result.Config.Settings["companion"] != "native" {
		t.Fatalf("configuration = %#v", result.Config)
	}
}

func TestMainRelativeContextSelection(t *testing.T) {
	root := t.TempDir()
	base := filepath.Join(root, "main")
	if err := os.Mkdir(base, 0700); err != nil {
		t.Fatal(err)
	}
	for path, value := range map[string]string{"main/main.yml": "count: 1\n", "main/extra.yml": "settings: {value: derived}\n", "extra.yml": "settings: {value: fallback}\n"} {
		if err := os.WriteFile(filepath.Join(root, path), []byte(value), 0600); err != nil {
			t.Fatal(err)
		}
	}
	link := filepath.Join(root, "link.yml")
	if err := os.Symlink(filepath.Join(base, "main.yml"), link); err != nil {
		t.Fatal(err)
	}
	companion := configkit.Input{Source: configkit.Bytes("companion", []byte("config: {imports: [{path: extra.yml}]}\n")), Imports: true, MainRelative: &configkit.MainRelativeContext{Fallback: &configkit.FilesystemContext{Root: root, BaseDir: root}}}
	opts := configkit.LayeredOptions[layeredFacadeConfig]{Underlays: []configkit.Underlay{{Inputs: []configkit.Input{companion}}}}
	result, err := configkit.LoadLayered(configkit.Input{Source: configkit.File(link), Filesystem: &configkit.FilesystemContext{Root: root}}, opts)
	if err != nil {
		t.Fatalf("%v: %#v", err, err.(*configkit.LoadError).Diagnostics())
	}
	if got := result.Config.Settings["value"]; got != "derived" {
		t.Fatalf("derived value = %q", got)
	}
	result, err = configkit.LoadLayered(configkit.Input{Source: configkit.NoSource()}, opts)
	if err != nil {
		t.Fatalf("%v: %#v", err, err.(*configkit.LoadError).Diagnostics())
	}
	if got := result.Config.Settings["value"]; got != "fallback" {
		t.Fatalf("fallback value = %q", got)
	}
}