package main

import (
	"bytes"
	"errors"
	"io"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"github.com/yourusername/caldav-server/internal/db"
)

// writeTestConfig creates a minimal config.yaml in dir and returns its path.
func writeTestConfig(t *testing.T, dir string) string {
	t.Helper()
	cfgPath := filepath.Join(dir, "config.yaml")
	dataDir := filepath.Join(dir, "data")
	content := "storage:\n  data_dir: " + dataDir + "\n" +
		"users:\n" +
		"  alice:\n" +
		"    password: \"$2a$10$9.WEs0uz5TaNJLQbSTLrX.Te.BIe8XTTykVRzZbSHQMEkyFb8Sq/O\"\n" +
		"  bob:\n" +
		"    password: \"$2a$10$9.WEs0uz5TaNJLQbSTLrX.Te.BIe8XTTykVRzZbSHQMEkyFb8Sq/O\"\n"
	if err := os.WriteFile(cfgPath, []byte(content), 0o644); err != nil {
		t.Fatalf("writing test config: %v", err)
	}
	return cfgPath
}

// runCLI runs the CLI's run() function, capturing stdout/stderr, and
// returns (exit code, combined stdout+stderr).
func runCLI(t *testing.T, args ...string) (int, string) {
	t.Helper()

	oldStdout, oldStderr := os.Stdout, os.Stderr
	r, w, err := os.Pipe()
	if err != nil {
		t.Fatalf("os.Pipe: %v", err)
	}
	os.Stdout = w
	os.Stderr = w
	defer func() {
		os.Stdout = oldStdout
		os.Stderr = oldStderr
	}()

	code := run(args)

	w.Close()
	var buf bytes.Buffer
	io.Copy(&buf, r)
	return code, buf.String()
}

func TestCalendarShareUnshareLifecycle(t *testing.T) {
	dir := t.TempDir()
	cfgPath := writeTestConfig(t, dir)

	code, out := runCLI(t, "-config", cfgPath, "calendar", "share", "alice", "work", "bob", "write")
	if code != 0 {
		t.Fatalf("share exit code = %d, output: %s", code, out)
	}
	if !strings.Contains(out, "shared") {
		t.Errorf("output = %q, want to contain 'shared'", out)
	}

	code, out = runCLI(t, "-config", cfgPath, "calendar", "shares", "alice", "work")
	if code != 0 {
		t.Fatalf("shares exit code = %d, output: %s", code, out)
	}
	if !strings.Contains(out, "bob") || !strings.Contains(out, "write") {
		t.Errorf("output = %q, want to contain bob/write", out)
	}

	code, out = runCLI(t, "-config", cfgPath, "calendar", "unshare", "alice", "work", "bob")
	if code != 0 {
		t.Fatalf("unshare exit code = %d, output: %s", code, out)
	}

	code, out = runCLI(t, "-config", cfgPath, "calendar", "shares", "alice", "work")
	if code != 0 {
		t.Fatalf("shares (after unshare) exit code = %d, output: %s", code, out)
	}
	if !strings.Contains(out, "not shared with anyone") {
		t.Errorf("output = %q, want 'not shared with anyone'", out)
	}
}

func TestCalendarShareInvalidPermission(t *testing.T) {
	dir := t.TempDir()
	cfgPath := writeTestConfig(t, dir)

	code, out := runCLI(t, "-config", cfgPath, "calendar", "share", "alice", "work", "bob", "admin")
	if code != 2 {
		t.Errorf("exit code = %d, want 2; output: %s", code, out)
	}
	if !strings.Contains(out, "invalid permission") {
		t.Errorf("output = %q, want 'invalid permission'", out)
	}
}

func TestCalendarUnshareNotFound(t *testing.T) {
	dir := t.TempDir()
	cfgPath := writeTestConfig(t, dir)

	code, out := runCLI(t, "-config", cfgPath, "calendar", "unshare", "alice", "ghost", "bob")
	if code != 1 {
		t.Errorf("exit code = %d, want 1; output: %s", code, out)
	}
	if !strings.Contains(out, "not found") {
		t.Errorf("output = %q, want 'not found'", out)
	}
}

func TestAddressBookShareUnshareLifecycle(t *testing.T) {
	dir := t.TempDir()
	cfgPath := writeTestConfig(t, dir)

	code, out := runCLI(t, "-config", cfgPath, "addressbook", "share", "alice", "contacts", "bob", "read")
	if code != 0 {
		t.Fatalf("share exit code = %d, output: %s", code, out)
	}

	code, out = runCLI(t, "-config", cfgPath, "addressbook", "shares", "alice", "contacts")
	if code != 0 {
		t.Fatalf("shares exit code = %d, output: %s", code, out)
	}
	if !strings.Contains(out, "bob") || !strings.Contains(out, "read") {
		t.Errorf("output = %q, want to contain bob/read", out)
	}

	code, out = runCLI(t, "-config", cfgPath, "addressbook", "unshare", "alice", "contacts", "bob")
	if code != 0 {
		t.Fatalf("unshare exit code = %d, output: %s", code, out)
	}
}

func TestUnknownUserWarningDoesNotBlockShare(t *testing.T) {
	dir := t.TempDir()
	cfgPath := writeTestConfig(t, dir)

	code, out := runCLI(t, "-config", cfgPath, "calendar", "share", "alice", "work", "carol", "read")
	if code != 0 {
		t.Fatalf("exit code = %d, output: %s", code, out)
	}
	if !strings.Contains(out, "warning") || !strings.Contains(out, "carol") {
		t.Errorf("output = %q, want a warning about unknown user carol", out)
	}
	if !strings.Contains(out, "shared") {
		t.Errorf("output = %q, want the share to still succeed", out)
	}
}

func TestNoArgsShowsUsage(t *testing.T) {
	dir := t.TempDir()
	// No config needed since usage() is printed before config.Load for
	// missing subcommands.
	code, out := runCLI(t, "-config", filepath.Join(dir, "missing.yaml"))
	if code != 2 {
		t.Errorf("exit code = %d, want 2", code)
	}
	if !strings.Contains(out, "Usage") {
		t.Errorf("output = %q, want usage text", out)
	}
}

func TestUnknownCommand(t *testing.T) {
	dir := t.TempDir()
	cfgPath := writeTestConfig(t, dir)

	code, out := runCLI(t, "-config", cfgPath, "bogus")
	if code != 2 {
		t.Errorf("exit code = %d, want 2", code)
	}
	if !strings.Contains(out, "unknown command") {
		t.Errorf("output = %q, want 'unknown command'", out)
	}
}

// Sanity check that the CLI and internal/db agree on ErrShareNotFound
// being surfaced (not swallowed) through the exit code / error message.
func TestUnshareErrorIsShareNotFound(t *testing.T) {
	dir := t.TempDir()
	dbase, err := db.Open(filepath.Join(dir, "test.db"))
	if err != nil {
		t.Fatalf("db.Open: %v", err)
	}
	defer dbase.Close()

	err = dbase.UnshareCalendar("alice", "work", "bob")
	if !errors.Is(err, db.ErrShareNotFound) {
		t.Errorf("err = %v, want ErrShareNotFound", err)
	}
}