package proc

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

type AMDReader struct {
	hwmonDir string
	driver   string
}

type PowerState struct {
	lastEnergy uint64
	lastTime   time.Time
}

func NewAMDReader() (*AMDReader, error) {
	// Locate AMD k10temp or zenpower hwmon path
	matches, err := filepath.Glob("/sys/class/hwmon/hwmon*")
	if err != nil {
		return nil, err
	}

	for _, dir := range matches {
		b, err := os.ReadFile(filepath.Join(dir, "name"))
		if err != nil {
			continue
		}
		drv := strings.TrimSpace(string(b))
		if drv == "k10temp" || drv == "zenpower" {
			return &AMDReader{
				hwmonDir: dir,
				driver:   drv,
			}, nil
		}
	}

	return nil, fmt.Errorf("k10temp/zenpower driver not found under /sys/class/hwmon/")
}

func (r *AMDReader) ReadTemperatureSensors() ([]TempSensor, error) {
	inputs, err := filepath.Glob(filepath.Join(r.hwmonDir, "temp*_input"))
	if err != nil || len(inputs) == 0 {
		return nil, fmt.Errorf("no temperature inputs found in %s", r.hwmonDir)
	}

	temps := []TempSensor{}

	for _, inputPath := range inputs {
		valBytes, err := os.ReadFile(inputPath)
		if err != nil {
			continue
		}

		milliC, err := strconv.ParseFloat(strings.TrimSpace(string(valBytes)), 64)
		if err != nil {
			continue
		}

		labelPath := strings.TrimSuffix(inputPath, "_input") + "_label"
		label := ""
		if lBytes, err := os.ReadFile(labelPath); err == nil {
			label = strings.TrimSpace(string(lBytes))
		} else {
			label = filepath.Base(strings.TrimSuffix(inputPath, "_input"))
		}

		temps = append(temps, TempSensor{
			Name:  label,
			TempC: milliC / 1000.0,
		})
	}

	return temps, nil
}