package config

import (
	"fmt"
	"os"
	"path/filepath"
	"strings"
	"time"

	"gopkg.in/yaml.v3"
)

var (
	Global      *GlobalConfig
	Account     *AccountConfig
	HttpTimeOut time.Duration = 5 * time.Second
)

type GlobalConfig struct {
	QMTBaseURL string            `yaml:"qmt_base_url"`
	QMTToken   string            `yaml:"qmt_token"`
	APIHost    string            `yaml:"api_host"`
	QMTDataDir string            `yaml:"qmt_data_dir"`
	Hosts      map[string]string `yaml:"hosts"`
}

type AccountConfig struct {
	AccountID        string  `yaml:"account_id"`
	HostKey          string  `yaml:"host_key"`
	OrderTimeoutSec  int     `yaml:"order_timeout_seconds"`
	BuyValue         float64 `yaml:"buy_value"`
	MinCashRatio     float64 `yaml:"min_cash_ratio"`
	LossTriggerPct   float64 `yaml:"loss_trigger_pct"`
	GridStepPct      float64 `yaml:"grid_step_pct"`
	MinProfitPct     float64 `yaml:"min_profit_pct"`
	WatchTimeoutSec  int     `yaml:"watch_timeout_seconds"`
	ReboundThreshold float64 `yaml:"rebound_threshold"`
}

// Load 根据 global.yaml 中的 hosts 映射加载当前计算机的账户配置。
func Load(etcDir string) error {
	var global GlobalConfig
	if err := readYAML(filepath.Join(etcDir, "global.yaml"), &global); err != nil {
		return err
	}
	hostname, err := os.Hostname()
	if err != nil {
		return fmt.Errorf("读取计算机名失败: %w", err)
	}
	if global.QMTBaseURL == "" || global.APIHost == "" || global.QMTDataDir == "." {
		return fmt.Errorf("Global 配置缺少必要参数")
	}
	if err := os.MkdirAll(global.QMTDataDir, 0o755); err != nil {
		return fmt.Errorf("创建目录 %s 失败: %w", global.QMTDataDir, err)
	}

	accountFile := hostAccountFile(global.Hosts, hostname)
	if accountFile == "" {
		return fmt.Errorf("global.yaml 未配置计算机 %q", hostname)
	}
	if filepath.Ext(accountFile) == "" {
		accountFile += ".yaml"
	}

	var account AccountConfig
	if err := readYAML(filepath.Join(etcDir, accountFile), &account); err != nil {
		return err
	}

	if account.BuyValue <= 0 || account.GridStepPct <= 0 {
		return fmt.Errorf("buy_value、grid_step_pct 和超时时间必须大于 0")
	}

	Global = &global
	Account = &account

	return nil
}

func readYAML(path string, dest any) error {
	raw, err := os.ReadFile(path)
	if err != nil {
		return fmt.Errorf("读取配置 %s 失败: %w", path, err)
	}
	if err := yaml.Unmarshal(raw, dest); err != nil {
		return fmt.Errorf("解析配置 %s 失败: %w", path, err)
	}
	return nil
}

func hostAccountFile(hosts map[string]string, hostname string) string {
	for host, file := range hosts {
		if strings.EqualFold(strings.TrimSpace(host), strings.TrimSpace(hostname)) {
			return strings.TrimSpace(file)
		}
	}
	return ""
}