package cli

import (
	"context"
	"fmt"
	"io"
	"strings"

	"gitea.maximumdirect.net/eric/distributor/internal/app"
)

const (
	exitOK    = 0
	exitError = 1
	exitUsage = 2
)

func Execute(ctx context.Context, args []string, stdout, stderr io.Writer) int {
	if len(args) == 0 {
		printRootHelp(stdout)
		return exitOK
	}

	switch args[0] {
	case "-h", "--help", "help":
		printRootHelp(stdout)
		return exitOK
	case "version":
		return versionCommand(ctx, args[1:], stdout, stderr)
	case "run":
		return runCommand(ctx, args[1:], stdout, stderr)
	case "validate":
		return validateCommand(ctx, args[1:], stdout, stderr)
	case "inspect":
		return inspectCommand(ctx, args[1:], stdout, stderr)
	case "manifest":
		return manifestCommand(ctx, args[1:], stdout, stderr)
	default:
		fmt.Fprintf(stderr, "%s: unknown command %q\n\n", app.Name, args[0])
		printRootHelp(stderr)
		return exitUsage
	}
}

func printRootHelp(w io.Writer) {
	fmt.Fprintf(w, `%s validates and publishes manifested report bundles.

Usage:
  %s <command> [options]

Commands:
  version    Print version information
  run        Run configured distribution pipelines
  validate   Validate a source bundle or bundle tree
  inspect    Inspect bundles or distributor state
  manifest   Create source bundle manifests

Use "%s <command> --help" for command-specific help.
`, app.Name, app.Name, app.Name)
}

func hasHelp(args []string) bool {
	for _, arg := range args {
		if arg == "-h" || arg == "--help" {
			return true
		}
	}
	return false
}

func fail(stderr io.Writer, err error) int {
	fmt.Fprintf(stderr, "%s: %s\n", app.Name, err)
	return exitError
}

func rejectExtraArgs(stderr io.Writer, command string, args []string) bool {
	if len(args) == 0 {
		return false
	}
	fmt.Fprintf(stderr, "%s: %s does not accept arguments: %s\n", app.Name, command, strings.Join(args, " "))
	return true
}

func parseOptionalPathArg(stderr io.Writer, command string, args []string) (string, bool) {
	if len(args) > 1 {
		fmt.Fprintf(stderr, "%s: %s accepts at most one path\n", app.Name, command)
		return "", false
	}
	if len(args) == 0 {
		return "", true
	}
	return args[0], true
}

func rejectPositionalArgs(stderr io.Writer, command string, args []string) bool {
	if len(args) == 0 {
		return false
	}
	fmt.Fprintf(stderr, "%s: %s does not accept positional arguments: %v\n", app.Name, command, args)
	return true
}