package internal

import (
	"io"

	"github.com/getkin/kin-openapi/openapi3"
	"github.com/spf13/cobra"
	"github.com/tufin/oasdiff/diff"
)

func getSummaryCmd() *cobra.Command {
	flags := DiffFlags{}

	cmd := cobra.Command{
		Use:   "summary base revision [flags]",
		Short: "Generate a diff summary",
		Long:  "Display a summary of changes between base and revision specs." + specHelp,
		Args:  getParseArgs(&flags),
		RunE:  getRun(&flags, runSummary),
	}

	cmd.PersistentFlags().BoolVarP(&flags.composed, "composed", "c", false, "work in 'composed' mode, compare paths in all specs matching base and revision globs")
	enumWithOptions(&cmd, newEnumValue([]string{FormatYAML, FormatJSON}, FormatYAML, &flags.format), "format", "f", "output format")
	cmd.PersistentFlags().VarP(newEnumSliceValue(diff.ExcludeDiffOptions, nil, &flags.excludeElements), "exclude-elements", "e", "comma-separated list of elements to exclude")
	cmd.PersistentFlags().StringVarP(&flags.matchPath, "match-path", "p", "", "include only paths that match this regular expression")
	cmd.PersistentFlags().StringVarP(&flags.filterExtension, "filter-extension", "", "", "exclude paths and operations with an OpenAPI Extension matching this regular expression")
	cmd.PersistentFlags().IntVarP(&flags.circularReferenceCounter, "max-circular-dep", "", 5, "maximum allowed number of circular dependencies between objects in OpenAPI specs")
	cmd.PersistentFlags().StringVarP(&flags.prefixBase, "prefix-base", "", "", "add this prefix to paths in base-spec before comparison")
	cmd.PersistentFlags().StringVarP(&flags.prefixRevision, "prefix-revision", "", "", "add this prefix to paths in revised-spec before comparison")
	cmd.PersistentFlags().StringVarP(&flags.stripPrefixBase, "strip-prefix-base", "", "", "strip this prefix from paths in base-spec before comparison")
	cmd.PersistentFlags().StringVarP(&flags.stripPrefixRevision, "strip-prefix-revision", "", "", "strip this prefix from paths in revised-spec before comparison")
	cmd.PersistentFlags().BoolVarP(&flags.includePathParams, "include-path-params", "", false, "include path parameter names in endpoint matching")
	cmd.PersistentFlags().BoolVarP(&flags.failOnDiff, "fail-on-diff", "", false, "exit with return code 1 when any change is found")

	return &cmd
}

func runSummary(flags Flags, stdout io.Writer) (bool, *ReturnError) {

	openapi3.CircularReferenceCounter = flags.getCircularReferenceCounter()

	diffReport, _, err := calcDiff(flags)
	if err != nil {
		return false, err
	}

	if err := outputSummary(stdout, diffReport, flags.getFormat()); err != nil {
		return false, err
	}

	return flags.getFailOnDiff() && !diffReport.Empty(), nil
}

func outputSummary(stdout io.Writer, diffReport *diff.Diff, format string) *ReturnError {
	switch format {
	case FormatYAML:
		if err := printYAML(stdout, diffReport.GetSummary()); err != nil {
			return getErrFailedPrint("summary", err)
		}
	case FormatJSON:

		if err := printJSON(stdout, diffReport.GetSummary()); err != nil {
			return getErrFailedPrint("summary", err)
		}
	default:
		return getErrUnsupportedFormat(format)
	}

	return nil
}