package compass_test

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

	"git.golem15.com/golem15/summercms/modules/compass"
)

// writeConfig lays out a config directory: base sections and a development
// override of one of them.
func writeConfig(dir string) error {
	files := map[string]string{
		"app.yaml":                 "name: Acme\ndebug: false\n",
		"mail.yaml":                "driver: log\nfrom: blog@example.com\n",
		"env/development/app.yaml": "debug: true\n",
	}
	for name, body := range files {
		path := filepath.Join(dir, filepath.FromSlash(name))
		if err := os.MkdirAll(filepath.Dir(path), 0o755); err != nil {
			return err
		}
		if err := os.WriteFile(path, []byte(body), 0o644); err != nil {
			return err
		}
	}
	return nil
}

type mailSettings struct {
	Driver string `koanf:"driver"`
	From   string `koanf:"from"`
}

func ExampleOpen() {
	dir, err := os.MkdirTemp("", "acme-config")
	if err != nil {
		fmt.Println(err)
		return
	}
	defer os.RemoveAll(dir)
	if err := writeConfig(dir); err != nil {
		fmt.Println(err)
		return
	}

	// Environ stands in for the process environment (nil reads os.Environ).
	cfg, err := compass.Open(compass.Options{
		Dir:     dir,
		Env:     "development",
		Environ: []string{"SUMMER_MAIL__DRIVER=smtp"},
	})
	if err != nil {
		fmt.Println(err)
		return
	}

	// A plugin's embedded config/config.yaml becomes its defaults.
	plugin := fstest.MapFS{"config/config.yaml": {Data: []byte("posts_per_page: 10\n")}}
	if err := cfg.MergePlugin("acme.blog", plugin); err != nil {
		fmt.Println(err)
		return
	}

	fmt.Println(cfg.String("app.name"), cfg.Bool("app.debug"), cfg.Int("acme.blog.posts_per_page"))
	var mail mailSettings
	if err := cfg.LoadSection("mail", &mail); err != nil {
		fmt.Println(err)
		return
	}
	fmt.Println(mail.Driver, mail.From)
	_, found := cfg.Lookup("app.timezone")
	fmt.Println(cfg.Environment(), found)

	// A runtime override, saved to env/development/overrides.yaml.
	if err := cfg.Set("acme.blog.posts_per_page", 25); err != nil {
		fmt.Println(err)
		return
	}
	if err := cfg.Persist(); err != nil {
		fmt.Println(err)
		return
	}
	saved, _ := os.ReadFile(filepath.Join(dir, "env", "development", "overrides.yaml"))
	fmt.Print(string(saved))
	// Output:
	// Acme true 10
	// smtp blog@example.com
	// development false
	// acme:
	//     blog:
	//         posts_per_page: 25
}