package clicmd

import (
	"io"
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func TestSaveConfigIsOwnerOnlyAndAtomic(t *testing.T) {
	dir := filepath.Join(t.TempDir(), "nested")
	path := filepath.Join(dir, "config.json")

	want := ConfigFile{Server: "https://p.example.com", Token: "pgs_abcdefghijklmnop_secret", Output: "json"}
	if err := SaveConfig(path, want); err != nil {
		t.Fatalf("SaveConfig: %v", err)
	}

	fi, err := os.Stat(path)
	if err != nil {
		t.Fatal(err)
	}
	if perm := fi.Mode().Perm(); perm != 0o600 {
		t.Errorf("config mode = %#o, want 0600 — it holds a token", perm)
	}
	if di, err := os.Stat(dir); err == nil {
		if perm := di.Mode().Perm(); perm&0o077 != 0 {
			t.Errorf("config directory mode = %#o, want no group or other bits", perm)
		}
	}

	got, err := LoadConfig(path, io.Discard)
	if err != nil {
		t.Fatalf("LoadConfig: %v", err)
	}
	if got != want {
		t.Errorf("round trip = %+v, want %+v", got, want)
	}

	// The temporary file is written in the destination directory; leaving one
	// behind would leave a mode-0600 copy of the token lying around.
	ents, err := os.ReadDir(dir)
	if err != nil {
		t.Fatal(err)
	}
	if len(ents) != 1 || ents[0].Name() != "config.json" {
		names := make([]string, len(ents))
		for i, e := range ents {
			names[i] = e.Name()
		}
		t.Errorf("directory contains %q, want only config.json", names)
	}
}

func TestSaveConfigReplacesInPlace(t *testing.T) {
	path := filepath.Join(t.TempDir(), "config.json")
	if err := SaveConfig(path, ConfigFile{Server: "https://one.example.com"}); err != nil {
		t.Fatal(err)
	}
	if err := SaveConfig(path, ConfigFile{Server: "https://two.example.com"}); err != nil {
		t.Fatal(err)
	}
	got, err := LoadConfig(path, io.Discard)
	if err != nil {
		t.Fatal(err)
	}
	if got.Server != "https://two.example.com" {
		t.Errorf("server = %q, want the second write", got.Server)
	}
}

func TestLoadConfig(t *testing.T) {
	t.Run("a missing file is the normal state on CI", func(t *testing.T) {
		got, err := LoadConfig(filepath.Join(t.TempDir(), "absent.json"), io.Discard)
		if err != nil {
			t.Fatalf("err = %v, want nil", err)
		}
		if got != (ConfigFile{}) {
			t.Errorf("got %+v, want the zero value", got)
		}
	})

	t.Run("an empty path means there is no config file", func(t *testing.T) {
		if _, err := LoadConfig("", io.Discard); err != nil {
			t.Fatalf("err = %v, want nil", err)
		}
	})

	t.Run("malformed JSON is reported, not ignored", func(t *testing.T) {
		path := filepath.Join(t.TempDir(), "config.json")
		os.WriteFile(path, []byte("{not json"), 0o600)
		if _, err := LoadConfig(path, io.Discard); err == nil {
			t.Fatal("expected an error")
		}
	})

	t.Run("a readable-by-others config warns", func(t *testing.T) {
		path := filepath.Join(t.TempDir(), "config.json")
		os.WriteFile(path, []byte(`{"token":"pgs_abcdefghijklmnop_secret"}`), 0o644)
		var warn strings.Builder
		if _, err := LoadConfig(path, &warn); err != nil {
			t.Fatal(err)
		}
		if !strings.Contains(warn.String(), "chmod 600") {
			t.Errorf("warning = %q, want it to say how to fix the mode", warn.String())
		}
		if strings.Contains(warn.String(), "secret") {
			t.Error("the warning printed the token it was warning about")
		}
	})
}

func TestRedactToken(t *testing.T) {
	cases := []struct{ in, want string }{
		{"pgs_abcdefghijklmnop_thesecrethalf", "pgs_abcdefghijklmnop_…"},
		{"", ""},
		{"garbage", "…"},
		{"pgs_onlytwo", "…"},
		// The secret half is base64url, so it can itself contain underscores;
		// SplitN with n=3 keeps them in the part that gets dropped.
		{"pgs_abcdefghijklmnop_a_b_c", "pgs_abcdefghijklmnop_…"},
	}
	for _, tc := range cases {
		if got := redactToken(tc.in); got != tc.want {
			t.Errorf("redactToken(%q) = %q, want %q", tc.in, got, tc.want)
		}
	}
}

func TestDefaultConfigPathPrefersEnv(t *testing.T) {
	t.Setenv("PAGES_CONFIG", "/tmp/explicit.json")
	if got := DefaultConfigPath(); got != "/tmp/explicit.json" {
		t.Errorf("DefaultConfigPath = %q", got)
	}
}