package system

import "log"

// DebugLogger, when non-nil, enables debug-level logging for the system package.
// Set this to the application's *log.Logger when config logging.level == "debug".
// When nil, no debug output is emitted.
var DebugLogger *log.Logger

// debugf logs a formatted message if DebugLogger is set.
func debugf(format string, args ...any) {
	if DebugLogger != nil {
		DebugLogger.Printf(format, args...)
	}
}

// SystemInfo holds system resource usage information.
type SystemInfo struct {
	TotalMemMB uint64  `json:"total_mem_mb"`
	UsedMemMB  uint64  `json:"used_mem_mb"`
	AvailMemMB uint64  `json:"avail_mem_mb"`
	MemPercent float64 `json:"mem_percent"`

	DiskTotalGB float64 `json:"disk_total_gb"`
	DiskUsedGB  float64 `json:"disk_used_gb"`
	DiskAvailGB float64 `json:"disk_avail_gb"`
	DiskPercent float64 `json:"disk_percent"`
	// DiskKnown (R-259) — the statfs on "/" SUCCEEDED. Without it, a failed measurement is
	// indistinguishable from an empty disk: readDiskUsage returned early on error and left every
	// figure above at its zero value, `usageColor(0)` is "nominal", and the dashboard drew
	// „0.0 GB / 0.0 GB (0%)" with a 0%-wide bar in the healthy colour. "We could not look" and
	// "there is plenty of room" were the same picture.
	//
	// This is the house three-state form, and this session rules it THE one (CONTEXT S-39):
	// an explicit `…Known bool` companion beside the figures, checked in the template before
	// anything is rendered — the shape `Offbox.StatsKnown` already uses, whose own comment says
	// "a 0%-wide bar over an unread store is a picture of emptiness, and a picture is a claim".
	DiskKnown bool `json:"disk_known"`

	HDDTotalGB    float64 `json:"hdd_total_gb,omitempty"`
	HDDUsedGB     float64 `json:"hdd_used_gb,omitempty"`
	HDDAvailGB    float64 `json:"hdd_avail_gb,omitempty"`
	HDDPercent    float64 `json:"hdd_percent,omitempty"`
	HDDConfigured bool    `json:"hdd_configured"`
	// HDDKnown (R-259) — as DiskKnown, for the configured HDD path. HDDConfigured is NOT a
	// substitute: it says a path was configured, not that reading it worked.
	HDDKnown bool `json:"hdd_known"`

	CPUPercent         float64 `json:"cpu_percent"`
	LoadAvg1           float64 `json:"load_avg_1"`
	LoadAvg5           float64 `json:"load_avg_5"`
	LoadAvg15          float64 `json:"load_avg_15"`
	TemperatureCelsius float64 `json:"temperature_celsius"`
	TemperatureSource  string  `json:"temperature_source,omitempty"`
}