package local

import (
	"fmt"
	"math"

	"git.apinb.com/ops/files/internal/storage"
	"github.com/shirou/gopsutil/v3/disk"
)

func (c *Client) diskStatus() (*storage.DiskStatus, error) {
	usage, err := disk.Usage(c.rootPath)
	if err != nil {
		return nil, fmt.Errorf("读取本地存储磁盘容量: %w", err)
	}
	level := "normal"
	if usage.Free < c.minimumFreeBytes {
		level = "critical"
	} else if c.minimumFreeBytes <= math.MaxUint64/2 && usage.Free < c.minimumFreeBytes*2 {
		level = "warning"
	}
	return &storage.DiskStatus{
		Path:             c.rootPath,
		TotalBytes:       usage.Total,
		UsedBytes:        usage.Used,
		FreeBytes:        usage.Free,
		UsedPercent:      usage.UsedPercent,
		MinimumFreeBytes: c.minimumFreeBytes,
		Level:            level,
	}, nil
}

func (c *Client) ensureCapacity(expectedSize int64) error {
	if expectedSize < 0 {
		return fmt.Errorf("文件大小不能为负数")
	}
	diskStatus, err := c.diskStatus()
	if err != nil {
		return err
	}
	requested := uint64(expectedSize)
	if requested > math.MaxUint64-c.minimumFreeBytes || diskStatus.FreeBytes < requested+c.minimumFreeBytes {
		return storage.ErrInsufficientSpace
	}
	return nil
}