package observability

import (
	"context"
	"database/sql"
	"errors"
	"runtime"
	"time"

	"git.yuntuo.hk/k2safe/orbit/internal/buildinfo"
)

// RuntimeConfig 是节点启动后实际生效的后台控制参数。
// 它只用于固定基数观测，不参与业务授权或持久化状态判断。
type RuntimeConfig struct {
	WorkflowTickInterval time.Duration
	ScheduleTickInterval time.Duration
	RecoveryTickInterval time.Duration
	BatchLimit           int
	ShutdownTimeout      time.Duration
}

// RecordRuntimeConfig records the effective bounded controller settings.
func (r *Registry) RecordRuntimeConfig(config RuntimeConfig) {
	if r == nil || config.WorkflowTickInterval <= 0 || config.ScheduleTickInterval <= 0 || config.RecoveryTickInterval <= 0 || config.BatchLimit <= 0 || config.ShutdownTimeout <= 0 {
		return
	}
	r.SetGauge("orbit_runtime_tick_interval_seconds", config.WorkflowTickInterval.Seconds(), Labels{"component": "workflow"})
	r.SetGauge("orbit_runtime_tick_interval_seconds", config.ScheduleTickInterval.Seconds(), Labels{"component": "schedule"})
	r.SetGauge("orbit_runtime_tick_interval_seconds", config.RecoveryTickInterval.Seconds(), Labels{"component": "execution_recovery"})
	r.SetGauge("orbit_runtime_batch_limit", float64(config.BatchLimit), nil)
	r.SetGauge("orbit_shutdown_timeout_seconds", config.ShutdownTimeout.Seconds(), nil)
}

// RecordDraining records whether this process has entered graceful shutdown.
// The value is a fixed, node-local gauge: 0 means serving and 1 means draining.
func (r *Registry) RecordDraining(draining bool) {
	if r == nil {
		return
	}
	value := 0.0
	if draining {
		value = 1
	}
	r.SetGauge("orbit_process_draining", value, nil)
}

// initializeProcess is called once by the registry constructor.
func (r *Registry) initializeProcess() {
	if r == nil {
		return
	}
	r.SetGauge("orbit_process_start_time_seconds", float64(r.started.Unix()), nil)
	r.RecordDraining(false)
	build := buildinfo.Current()
	r.SetGauge("orbit_build_info", 1, Labels{"go_version": build.GoVersion, "version": build.Version, "revision": build.Revision})
	r.RecordProcess()
	for _, component := range components {
		labels := Labels{"component": component}
		r.SetGauge("orbit_runtime_batch_last_success_timestamp_seconds", 0, labels)
		for _, outcome := range []string{"success", "error", "cancelled"} {
			r.AddCounter("orbit_runtime_batch_total", 0, Labels{"component": component, "outcome": outcome})
		}
	}
	for _, route := range []string{"worker_connect", "event_connect"} {
		r.SetGauge("orbit_websocket_connections", 0, Labels{"route": route})
		r.AddCounter("orbit_websocket_connections_total", 0, Labels{"route": route})
	}
}
func (r *Registry) RecordProcess() {
	if r == nil {
		return
	}
	r.SetGauge("orbit_process_uptime_seconds", time.Since(r.started).Seconds(), nil)
	r.SetGauge("orbit_go_goroutines", float64(runtime.NumGoroutine()), nil)
}
func (r *Registry) RecordBatch(component string, started time.Time, err error) {
	if r == nil {
		return
	}
	outcome := "success"
	if err != nil {
		outcome = "error"
		if errors.Is(err, context.Canceled) {
			outcome = "cancelled"
		}
	}
	r.AddCounter("orbit_runtime_batch_total", 1, Labels{"component": component, "outcome": outcome})
	r.ObserveHistogram("orbit_runtime_batch_duration_seconds", time.Since(started).Seconds(), Labels{"component": component})
	if err == nil {
		r.SetGauge("orbit_runtime_batch_last_success_timestamp_seconds", float64(time.Now().Unix()), Labels{"component": component})
	}
}

// RecordDatabase reads the local connection-pool snapshot; it issues no SQL.
func (r *Registry) RecordDatabase(s sql.DBStats) {
	r.SetGauge("orbit_db_connections_open", float64(s.OpenConnections), nil)
	r.SetGauge("orbit_db_connections_in_use", float64(s.InUse), nil)
	r.SetGauge("orbit_db_connections_idle", float64(s.Idle), nil)
	r.SetGauge("orbit_db_connections_max_open", float64(s.MaxOpenConnections), nil)
	r.SetCounter("orbit_db_wait_count_total", float64(s.WaitCount), nil)
	r.SetCounter("orbit_db_wait_duration_seconds_total", s.WaitDuration.Seconds(), nil)
}