package mining

import (
	"net/http"
)

// respondWithError(c, http.StatusNotFound, ErrCodeMinerNotFound, "xmrig not found", err.Error())
// respondWithError(c, http.StatusConflict, ErrCodeMinerExists, "xmrig already running", "")
const (
	ErrCodeMinerNotFound      = "MINER_NOT_FOUND"
	ErrCodeMinerExists        = "MINER_EXISTS"
	ErrCodeMinerNotRunning    = "MINER_NOT_RUNNING"
	ErrCodeInstallFailed      = "INSTALL_FAILED"
	ErrCodeStartFailed        = "START_FAILED"
	ErrCodeStopFailed         = "STOP_FAILED"
	ErrCodeInvalidConfig      = "INVALID_CONFIG"
	ErrCodeInvalidInput       = "INVALID_INPUT"
	ErrCodeUnsupportedMiner   = "UNSUPPORTED_MINER"
	ErrCodeNotSupported       = "NOT_SUPPORTED"
	ErrCodeConnectionFailed   = "CONNECTION_FAILED"
	ErrCodeServiceUnavailable = "SERVICE_UNAVAILABLE"
	ErrCodeTimeout            = "TIMEOUT"
	ErrCodeDatabaseError      = "DATABASE_ERROR"
	ErrCodeProfileNotFound    = "PROFILE_NOT_FOUND"
	ErrCodeProfileExists      = "PROFILE_EXISTS"
	ErrCodeInternalError      = "INTERNAL_ERROR"
)

// miningError := &MiningError{Code: ErrCodeStartFailed, Message: "failed to start xmrig", HTTPStatus: 500}
// miningError.WithCause(err).WithSuggestion("check logs")
type MiningError struct {
	Code       string
	Message    string
	Details    string
	Suggestion string
	Retryable  bool
	HTTPStatus int
	Cause      error
}

// e.Error() // "START_FAILED: failed to start miner 'xmrig' (exec: not found)"
func (e *MiningError) Error() string {
	if e.Cause != nil {
		return e.Code + ": " + e.Message + " (" + e.Cause.Error() + ")"
	}
	return e.Code + ": " + e.Message
}

// errors.As(e.Unwrap(), &target) // unwrap to inspect the underlying cause
func (e *MiningError) Unwrap() error {
	return e.Cause
}

// return ErrStartFailed("xmrig").WithCause(err)
func (e *MiningError) WithCause(err error) *MiningError {
	e.Cause = err
	return e
}

// return ErrInternal("nil response").WithDetails("stats API returned null body")
func (e *MiningError) WithDetails(details string) *MiningError {
	e.Details = details
	return e
}

// return ErrInstallFailed("xmrig").WithSuggestion("ensure curl is installed")
func (e *MiningError) WithSuggestion(suggestion string) *MiningError {
	e.Suggestion = suggestion
	return e
}

// if e.IsRetryable() { time.Sleep(backoff); retry() }
func (e *MiningError) IsRetryable() bool {
	return e.Retryable
}

// c.JSON(e.StatusCode(), e) // 404 for not-found, 500 for internal errors
func (e *MiningError) StatusCode() int {
	if e.HTTPStatus == 0 {
		return http.StatusInternalServerError
	}
	return e.HTTPStatus
}

// NewMiningError("START_FAILED", "failed to start xmrig").WithCause(err)
func NewMiningError(code, message string) *MiningError {
	return &MiningError{
		Code:       code,
		Message:    message,
		HTTPStatus: http.StatusInternalServerError,
	}
}

// return ErrMinerNotFound("xmrig").WithCause(err)
func ErrMinerNotFound(name string) *MiningError {
	return &MiningError{
		Code:       ErrCodeMinerNotFound,
		Message:    "miner '" + name + "' not found",
		Suggestion: "Check that the miner name is correct and that it is running",
		Retryable:  false,
		HTTPStatus: http.StatusNotFound,
	}
}

// return ErrMinerExists("xmrig")
func ErrMinerExists(name string) *MiningError {
	return &MiningError{
		Code:       ErrCodeMinerExists,
		Message:    "miner '" + name + "' is already running",
		Suggestion: "Stop the existing miner first or use a different configuration",
		Retryable:  false,
		HTTPStatus: http.StatusConflict,
	}
}

// return ErrMinerNotRunning("xmrig")
func ErrMinerNotRunning(name string) *MiningError {
	return &MiningError{
		Code:       ErrCodeMinerNotRunning,
		Message:    "miner '" + name + "' is not running",
		Suggestion: "Start the miner first before performing this operation",
		Retryable:  false,
		HTTPStatus: http.StatusBadRequest,
	}
}

// return ErrInstallFailed("xmrig").WithCause(err)
func ErrInstallFailed(minerType string) *MiningError {
	return &MiningError{
		Code:       ErrCodeInstallFailed,
		Message:    "failed to install " + minerType,
		Suggestion: "Check your internet connection and try again",
		Retryable:  true,
		HTTPStatus: http.StatusInternalServerError,
	}
}

// return ErrStartFailed("xmrig").WithCause(err)
func ErrStartFailed(name string) *MiningError {
	return &MiningError{
		Code:       ErrCodeStartFailed,
		Message:    "failed to start miner '" + name + "'",
		Suggestion: "Check the miner configuration and logs for details",
		Retryable:  true,
		HTTPStatus: http.StatusInternalServerError,
	}
}

// return ErrStopFailed("xmrig").WithCause(err)
func ErrStopFailed(name string) *MiningError {
	return &MiningError{
		Code:       ErrCodeStopFailed,
		Message:    "failed to stop miner '" + name + "'",
		Suggestion: "The miner process may need to be terminated manually",
		Retryable:  true,
		HTTPStatus: http.StatusInternalServerError,
	}
}

// return ErrInvalidConfig("wallet address is required")
func ErrInvalidConfig(reason string) *MiningError {
	return &MiningError{
		Code:       ErrCodeInvalidConfig,
		Message:    "invalid configuration: " + reason,
		Suggestion: "Review the configuration and ensure all required fields are provided",
		Retryable:  false,
		HTTPStatus: http.StatusBadRequest,
	}
}

// return ErrUnsupportedMiner("nicehash")
func ErrUnsupportedMiner(minerType string) *MiningError {
	return &MiningError{
		Code:       ErrCodeUnsupportedMiner,
		Message:    "unsupported miner type: " + minerType,
		Suggestion: "Use one of the supported miner types: xmrig, tt-miner",
		Retryable:  false,
		HTTPStatus: http.StatusBadRequest,
	}
}

// return ErrConnectionFailed("pool.minexmr.com:4444").WithCause(err)
func ErrConnectionFailed(target string) *MiningError {
	return &MiningError{
		Code:       ErrCodeConnectionFailed,
		Message:    "failed to connect to " + target,
		Suggestion: "Check network connectivity and try again",
		Retryable:  true,
		HTTPStatus: http.StatusServiceUnavailable,
	}
}

// return ErrTimeout("stats poll")
func ErrTimeout(operation string) *MiningError {
	return &MiningError{
		Code:       ErrCodeTimeout,
		Message:    "operation timed out: " + operation,
		Suggestion: "The operation is taking longer than expected, try again later",
		Retryable:  true,
		HTTPStatus: http.StatusGatewayTimeout,
	}
}

// return ErrDatabaseError("save profile")
func ErrDatabaseError(operation string) *MiningError {
	return &MiningError{
		Code:       ErrCodeDatabaseError,
		Message:    "database error during " + operation,
		Suggestion: "This may be a temporary issue, try again",
		Retryable:  true,
		HTTPStatus: http.StatusInternalServerError,
	}
}

// return ErrProfileNotFound("default-xmr")
func ErrProfileNotFound(id string) *MiningError {
	return &MiningError{
		Code:       ErrCodeProfileNotFound,
		Message:    "profile '" + id + "' not found",
		Suggestion: "Check that the profile ID is correct",
		Retryable:  false,
		HTTPStatus: http.StatusNotFound,
	}
}

// return ErrProfileExists("default-xmr")
func ErrProfileExists(name string) *MiningError {
	return &MiningError{
		Code:       ErrCodeProfileExists,
		Message:    "profile '" + name + "' already exists",
		Suggestion: "Use a different name or update the existing profile",
		Retryable:  false,
		HTTPStatus: http.StatusConflict,
	}
}

// return ErrInternal("unexpected nil response from stats API")
func ErrInternal(message string) *MiningError {
	return &MiningError{
		Code:       ErrCodeInternalError,
		Message:    message,
		Suggestion: "Please report this issue if it persists",
		Retryable:  true,
		HTTPStatus: http.StatusInternalServerError,
	}
}