package cli

import (
	"log/slog"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"git.avsdev.uk/Go/job-search/internal/logging"
	"github.com/spf13/cobra"
	"github.com/spf13/viper"
)

// The commands themselves are tested through the real command tree in
// cmd/jobsearch. These tests cover what that can't reach easily: switching
// to file logging, and Confirm's answers.

// setupDir changes into a new temporary directory holding an empty .env and
// config.yaml with the given contents, and isolates Viper and logging.
func setupDir(t *testing.T, config string) {
	t.Helper()
	t.Chdir(t.TempDir())
	writeFile(t, ".env", "")
	writeFile(t, "config.yaml", config)

	viper.Reset()
	oldLog := slog.Default()
	t.Cleanup(func() {
		viper.Reset()
		if err := logging.Shutdown(); err != nil {
			t.Error(err)
		}
		slog.SetDefault(oldLog)
		logging.SetLevel(slog.LevelInfo)
	})
}

func writeFile(t *testing.T, path, contents string) {
	t.Helper()
	if err := os.WriteFile(path, []byte(contents), 0o600); err != nil {
		t.Fatal(err)
	}
}

// newCommand returns a command with the shared flags bound to opts, as the
// root command has, after parsing args.
func newCommand(t *testing.T, opts *Options, args ...string) *cobra.Command {
	t.Helper()
	cmd := &cobra.Command{Use: "test"}
	opts.Bind(cmd)
	if err := cmd.ParseFlags(args); err != nil {
		t.Fatal(err)
	}
	return cmd
}

func TestRunSetupSwitchesToLogFile(t *testing.T) {
	setupDir(t, "logging:\n  level: info\n  file: ./app.log\n")
	opts := &Options{}
	cmd := newCommand(t, opts)

	conf, err := opts.RunSetup(cmd, true, false)
	if err != nil {
		t.Fatal(err)
	}
	if conf.Logging.File != "./app.log" {
		t.Errorf("Logging.File = %q", conf.Logging.File)
	}
	if !cmd.SilenceUsage {
		t.Error("RunSetup did not silence usage for runtime errors")
	}
	if !logging.IsFileLogger() {
		t.Fatal("logging was not switched to the log file")
	}

	slog.Info("written to the log file")
	if err := opts.Finish(); err != nil {
		t.Fatal(err)
	}
	if logging.IsFileLogger() {
		t.Error("Finish left the log file open")
	}
	b, err := os.ReadFile("app.log")
	if err != nil {
		t.Fatal(err)
	}
	if !strings.Contains(string(b), "written to the log file") {
		t.Errorf("app.log = %q", b)
	}
}

func TestRunSetupWithoutLogFileStaysOnTerminal(t *testing.T) {
	setupDir(t, "logging:\n  level: info\n")
	opts := &Options{}

	if _, err := opts.RunSetup(newCommand(t, opts), true, false); err != nil {
		t.Fatal(err)
	}
	if logging.IsFileLogger() {
		t.Error("switched to file logging with no log file configured")
	}
	if err := opts.Finish(); err != nil {
		t.Errorf("Finish without a log file: %v", err)
	}
}

func TestRunSetupTerminalLogIgnoresLogFile(t *testing.T) {
	setupDir(t, "logging:\n  file: ./app.log\n")
	opts := &Options{}

	if _, err := opts.RunSetup(newCommand(t, opts), true, true); err != nil {
		t.Fatal(err)
	}
	if logging.IsFileLogger() {
		t.Error("switched to file logging when terminal logging was asked for")
	}
	if _, err := os.Stat("app.log"); err == nil {
		t.Error("app.log was created")
	}
}

func TestRunSetupBadLogFile(t *testing.T) {
	setupDir(t, "logging:\n  file: ./missing-dir/app.log\n")
	opts := &Options{}

	_, err := opts.RunSetup(newCommand(t, opts), true, false)
	if err == nil || !strings.Contains(err.Error(), "opening log file") {
		t.Errorf("err = %v, want opening log file", err)
	}
}

// Without loading, the configuration only reflects the flags.
func TestRunSetupWithoutLoadingConfig(t *testing.T) {
	setupDir(t, "logging:\n  level: info\n")

	for args, want := range map[string]string{
		"":        "",
		"--debug": "debug",
		"--quiet": "error",
		"-d -q":   "debug", // --debug wins
	} {
		opts := &Options{}
		conf, err := opts.RunSetup(newCommand(t, opts, strings.Fields(args)...), false, true)
		if err != nil {
			t.Fatal(err)
		}
		if conf.Logging.Level != want {
			t.Errorf("%q: Logging.Level = %q, want %q", args, conf.Logging.Level, want)
		}
	}
}

func TestSetupInitialLogging(t *testing.T) {
	setupDir(t, "")
	for args, wantDebug := range map[string]bool{
		"--quiet": false,
		"--debug": true,
		"-q -d":   true, // --debug wins
	} {
		logging.SetLevel(slog.LevelInfo)
		SetupInitialLogging(newCommand(t, &Options{}, strings.Fields(args)...))
		if got := logging.IsDebugEnabled(); got != wantDebug {
			t.Errorf("%q: debug enabled = %v, want %v", args, got, wantDebug)
		}
	}
}

func TestConfirm(t *testing.T) {
	for input, want := range map[string]bool{
		"y\n":              true,
		"YES\n":            true,
		"  Yes  \n":        true,
		"n\n":              false,
		"No\n":             false,
		"maybe\n\ny\n":     true, // asks again until it gets an answer
		"what?\nno\nyes\n": false,
	} {
		if got := confirmWithInput(t, input); got != want {
			t.Errorf("Confirm with input %q = %v, want %v", input, got, want)
		}
	}
}

// confirmWithInput runs Confirm with input as standard input, discarding the
// prompt it prints.
func confirmWithInput(t *testing.T, input string) bool {
	t.Helper()
	dir := t.TempDir()
	in := filepath.Join(dir, "stdin")
	writeFile(t, in, input)
	stdin, err := os.Open(filepath.Clean(in))
	if err != nil {
		t.Fatal(err)
	}
	defer stdin.Close()
	stdout, err := os.Create(filepath.Clean(filepath.Join(dir, "stdout")))
	if err != nil {
		t.Fatal(err)
	}
	defer stdout.Close()

	oldIn, oldOut := os.Stdin, os.Stdout
	os.Stdin, os.Stdout = stdin, stdout
	defer func() { os.Stdin, os.Stdout = oldIn, oldOut }()

	return Confirm("Proceed?")
}