package configkit_test

import (
	"errors"
	"strings"
	"testing"

	configkit "gitea.maximumdirect.net/eric/ConfigKit"
)

type versionCountingReader struct {
	*strings.Reader
	reads int
}

func (r *versionCountingReader) Read(data []byte) (int, error) {
	r.reads++
	return r.Reader.Read(data)
}

func TestFacadeRejectsMissingVersionCheckerBeforeReading(t *testing.T) {
	t.Parallel()
	type configuration struct {
		Version string `yaml:"version"`
	}
	reader := &versionCountingReader{Reader: strings.NewReader("version: v1\n")}
	source := configkit.Reader("version.yml", reader)
	var defaults, resolutions, validations, checks int
	options := configkit.Options[configuration]{Definition: configkit.Definition[configuration]{
		Version:  &configkit.VersionRule{Path: configkit.Keys("version")},
		Defaults: func() configuration { defaults++; return configuration{} },
		Resolve:  func(*configuration, *configkit.Resolution) error { resolutions++; return nil },
		Validate: func(*configuration, *configkit.Validation) { validations++ },
	}}
	result, err := configkit.Load(source, options)
	var loadError *configkit.LoadError
	if result != nil || !errors.As(err, &loadError) {
		t.Fatalf("missing checker: result = %v, error = %v", result, err)
	}
	diagnostics := loadError.Diagnostics()
	if len(diagnostics) != 1 || diagnostics[0].Code != configkit.CodeOptionsInvalid {
		t.Fatalf("diagnostics = %v", diagnostics)
	}
	if reader.reads != 0 || defaults != 0 || resolutions != 0 || validations != 0 {
		t.Fatalf("invalid options performed work: reads=%d defaults=%d resolve=%d validate=%d", reader.reads, defaults, resolutions, validations)
	}
	options.Definition.Version.Check = func(version configkit.Version, validation *configkit.Validation) error {
		checks++
		if version != (configkit.Version{Present: true, Text: "v1"}) {
			t.Errorf("version = %#v", version)
		}
		validation.Warning(configkit.Keys("version"), "version accepted")
		return nil
	}
	result, err = configkit.Load(source, options)
	if err != nil || result == nil || result.Config.Version != "v1" {
		t.Fatalf("reuse with checker: result = %v, error = %v", result, err)
	}
	if checks != 1 || defaults != 1 || resolutions != 1 || validations != 1 {
		t.Fatalf("callback counts: check=%d defaults=%d resolve=%d validate=%d", checks, defaults, resolutions, validations)
	}
	diagnostics = result.Diagnostics()
	if len(diagnostics) != 1 || diagnostics[0].Code != configkit.CodeVersionWarning {
		t.Fatalf("version callback diagnostics = %v", diagnostics)
	}
}