package config

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

func writeFile(t *testing.T, dir, name, body string) string {
	t.Helper()
	p := filepath.Join(dir, name)
	if err := os.WriteFile(p, []byte(body), 0o644); err != nil {
		t.Fatalf("写测试配置失败: %v", err)
	}
	return p
}

func TestLoadCreatesDefaultFile(t *testing.T) {
	dir := t.TempDir()
	path := filepath.Join(dir, FileName)

	cfg, err := Load(path, dir)
	if err != nil {
		t.Fatalf("Load 失败: %v", err)
	}
	if !cfg.Created {
		t.Fatal("首次加载应标记为已生成")
	}
	if cfg.ListenIP != "0.0.0.0" || cfg.ListenPort != 17777 {
		t.Fatalf("默认监听地址不对: %s:%d", cfg.ListenIP, cfg.ListenPort)
	}
	if cfg.BackupKeep != 14 || !cfg.BackupEnabled || !cfg.ScreenPublic || !cfg.LogEnabled {
		t.Fatalf("默认值不对: %+v", cfg)
	}
	// 相对路径应解析到 exe 目录
	if cfg.DatabasePath != filepath.Join(dir, "daili.db") {
		t.Fatalf("数据库路径=%s", cfg.DatabasePath)
	}
	if cfg.BackupDir != filepath.Join(dir, "backup") || cfg.LogDir != filepath.Join(dir, "logs") {
		t.Fatalf("备份/日志目录=%s %s", cfg.BackupDir, cfg.LogDir)
	}

	data, err := os.ReadFile(path)
	if err != nil {
		t.Fatalf("默认配置文件未生成: %v", err)
	}
	text := string(data)
	for _, want := range []string{"listen_ip = 0.0.0.0", "listen_port = 17777", "代打台 配置文件（daili.ini）", "timezone ="} {
		if !strings.Contains(text, want) {
			t.Errorf("默认配置缺少 %q", want)
		}
	}

	// 再读一次不应重新生成
	cfg2, err := Load(path, dir)
	if err != nil {
		t.Fatal(err)
	}
	if cfg2.Created {
		t.Fatal("第二次加载不应标记为已生成")
	}
}

func TestLoadParsesValues(t *testing.T) {
	dir := t.TempDir()
	body := "\ufeff# 注释\n" +
		"listen_ip = 127.0.0.1\r\n" +
		"\r\n" +
		"listen_port = 19000\r\n" +
		"  database_path = data/mydb.db  \r\n" +
		"backup_enabled = no\r\n" +
		"backup_keep = 30\r\n" +
		"timezone = Asia/Shanghai\r\n" +
		"open_browser = 0\r\n" +
		"screen_public = false\r\n" +
		"log_enabled = on\r\n" +
		"log_dir = D:\\logs\r\n"
	path := writeFile(t, dir, FileName, body)

	cfg, err := Load(path, dir)
	if err != nil {
		t.Fatalf("Load 失败: %v", err)
	}
	if cfg.ListenIP != "127.0.0.1" || cfg.ListenPort != 19000 {
		t.Fatalf("监听=%s:%d", cfg.ListenIP, cfg.ListenPort)
	}
	if !cfg.LoopbackOnly() || cfg.PublicBind() {
		t.Fatal("127.0.0.1 应判定为仅本机")
	}
	if cfg.DatabasePath != filepath.Join(dir, "data", "mydb.db") {
		t.Fatalf("相对路径未按 exe 目录解析: %s", cfg.DatabasePath)
	}
	if cfg.BackupEnabled || cfg.BackupKeep != 30 {
		t.Fatalf("备份配置=%v/%d", cfg.BackupEnabled, cfg.BackupKeep)
	}
	if cfg.Timezone != "Asia/Shanghai" || cfg.OpenBrowser || cfg.ScreenPublic || !cfg.LogEnabled {
		t.Fatalf("其余配置不对: %+v", cfg)
	}
	if cfg.LogDir != "D:\\logs" {
		t.Fatalf("绝对路径被改写: %s", cfg.LogDir)
	}
	if cfg.Addr() != "127.0.0.1:19000" {
		t.Fatalf("Addr=%s", cfg.Addr())
	}
}

func TestLoadRejectsBadInput(t *testing.T) {
	cases := []struct {
		name string
		body string
		want string
	}{
		{"未知配置项", "listen_port = 1\nlisten_prt = 2\n", "未知配置项 listen_prt"},
		{"端口非数字", "\nlisten_port = abc\n", "listen_port 必须是数字"},
		{"端口越界", "listen_port = 70000\n", "必须在 1-65535 之间"},
		{"非法IP", "listen_ip = 300.1.1.1\n", "不是合法 IP"},
		{"布尔值非法", "open_browser = maybe\n", "必须是 true/false"},
		{"保留份数越界", "backup_keep = 0\n", "backup_keep 必须在 1-365 之间"},
		{"时区非法", "timezone = Mars/Base\n", "timezone"},
		{"重复配置", "listen_port = 1\nlisten_port = 2\n", "重复"},
		{"缺少等号", "listen_port 1\n", "缺少等号"},
		{"不支持分节", "[net]\nlisten_port = 1\n", "不支持分节"},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			dir := t.TempDir()
			path := writeFile(t, dir, FileName, c.body)
			before, _ := os.ReadFile(path)
			_, err := Load(path, dir)
			if err == nil {
				t.Fatalf("期望报错，实际通过")
			}
			if !strings.Contains(err.Error(), c.want) {
				t.Fatalf("错误信息 %q 不含 %q", err.Error(), c.want)
			}
			after, _ := os.ReadFile(path)
			if string(before) != string(after) {
				t.Fatal("出错时不应修改原文件")
			}
		})
	}
}

func TestErrorHasLineNumber(t *testing.T) {
	dir := t.TempDir()
	path := writeFile(t, dir, FileName, "# 注释\nlisten_ip = 0.0.0.0\nlisten_port = 99999\n")
	_, err := Load(path, dir)
	if err == nil {
		t.Fatal("期望报错")
	}
	if !strings.Contains(err.Error(), "第 3 行") {
		t.Fatalf("错误信息应带行号: %v", err)
	}
}

func TestValidateAfterOverride(t *testing.T) {
	dir := t.TempDir()
	path := writeFile(t, dir, FileName, "listen_port = 18080\n")
	cfg, err := Load(path, dir)
	if err != nil {
		t.Fatal(err)
	}
	cfg.ListenPort = 0
	if err := cfg.Validate(); err == nil {
		t.Fatal("覆盖后的非法端口应被拦截")
	}
}