//go:build linux

package sysinfo

import (
	"fmt"
	"os"
	"strings"
)

func collectPlatform() Info {
	return Info{
		CPU: cpuName(),
		GPU: gpuName(),
		RAM: totalRAM(),
	}
}

func cpuName() string {
	data, err := os.ReadFile("/proc/cpuinfo")
	if err != nil {
		return "unknown"
	}
	for _, line := range strings.Split(string(data), "\n") {
		if strings.HasPrefix(line, "model name") {
			parts := strings.SplitN(line, ":", 2)
			if len(parts) == 2 {
				return strings.TrimSpace(parts[1])
			}
		}
	}
	return "unknown"
}

func gpuName() string {
	entries, err := os.ReadDir("/sys/class/drm")
	if err != nil {
		return "unknown"
	}
	var gpus []string
	seen := map[string]bool{}
	for _, e := range entries {
		if !strings.HasPrefix(e.Name(), "card") || strings.Contains(e.Name(), "-") {
			continue
		}
		labelPath := "/sys/class/drm/" + e.Name() + "/device/label"
		if data, err := os.ReadFile(labelPath); err == nil {
			name := strings.TrimSpace(string(data))
			if name != "" && !seen[name] {
				seen[name] = true
				gpus = append(gpus, name)
				continue
			}
		}

		ueventPath := "/sys/class/drm/" + e.Name() + "/device/uevent"
		if data, err := os.ReadFile(ueventPath); err == nil {
			for _, line := range strings.Split(string(data), "\n") {
				if strings.HasPrefix(line, "DRIVER=") {
					drv := strings.TrimPrefix(line, "DRIVER=")
					if drv != "" && !seen[drv] {
						seen[drv] = true
						gpus = append(gpus, drv)
					}
				}
			}
		}
	}
	if len(gpus) == 0 {
		return "unknown"
	}
	return strings.Join(gpus, ", ")
}

func totalRAM() string {
	data, err := os.ReadFile("/proc/meminfo")
	if err != nil {
		return "unknown"
	}
	for _, line := range strings.Split(string(data), "\n") {
		if strings.HasPrefix(line, "MemTotal:") {
			fields := strings.Fields(line)
			if len(fields) >= 2 {
				var kb uint64
				_, err := fmt.Sscanf(fields[1], "%d", &kb)
				if err != nil {
					return "unknown"
				}
				gb := float64(kb) / (1024 * 1024)
				if gb >= 1 {
					return fmt.Sprintf("%.0f GB", gb)
				}
				mb := float64(kb) / 1024
				return fmt.Sprintf("%.0f MB", mb)
			}
		}
	}
	return "unknown"
}