// Package webhook provides functionality for sending and validating webhooks
package webhook

import (
	"errors"
	"fmt"
	"net/http"
)

// Common webhook error types
var (
	// ErrInvalidConfig indicates missing or invalid configuration values
	ErrInvalidConfig = errors.New("invalid webhook configuration")

	// ErrPayloadMarshall indicates a failure to marshal the webhook payload
	ErrPayloadMarshall = errors.New("failed to marshal webhook payload")

	// ErrRequestCreation indicates a failure to create the HTTP request
	ErrRequestCreation = errors.New("failed to create webhook request")

	// ErrRequestFailed indicates a permanent failure in the webhook request
	ErrRequestFailed = errors.New("webhook request failed")

	// ErrTooManyRequests indicates rate limiting by the webhook endpoint
	ErrTooManyRequests = errors.New("rate limit exceeded")

	// ErrMaxRetriesReached indicates all retry attempts have been exhausted
	ErrMaxRetriesReached = errors.New("maximum retries reached")

	// ErrInvalidSignature indicates webhook signature validation failed
	ErrInvalidSignature = errors.New("invalid webhook signature")
)

// Error represents a webhook-specific error with detailed context
type Error struct {
	// Op is the operation that failed (e.g., "send", "validate")
	Op string

	// Code is the HTTP status code (if applicable)
	Code int

	// Err is the underlying error
	Err error

	// Details contains additional error context
	Details string
}

// Error returns a string representation of the error
func (e *Error) Error() string {
	var msg string
	if e.Code > 0 {
		msg = fmt.Sprintf("webhook %s failed with status %d", e.Op, e.Code)
	} else {
		msg = fmt.Sprintf("webhook %s failed", e.Op)
	}

	if e.Details != "" {
		msg = fmt.Sprintf("%s: %s", msg, e.Details)
	}

	if e.Err != nil {
		msg = fmt.Sprintf("%s: %v", msg, e.Err)
	}

	return msg
}

// Unwrap returns the underlying error
func (e *Error) Unwrap() error {
	return e.Err
}

// Is reports whether target matches this error
func (e *Error) Is(target error) bool {
	return errors.Is(e.Err, target)
}

// NewError creates a new webhook error
func NewError(op string, err error, details string) *Error {
	return &Error{
		Op:      op,
		Err:     err,
		Details: details,
	}
}

// NewHTTPError creates a new webhook error with HTTP status code
func NewHTTPError(op string, code int, err error, details string) *Error {
	return &Error{
		Op:      op,
		Code:    code,
		Err:     err,
		Details: details,
	}
}

// IsTemporaryError returns true if the error is temporary and the operation can be retried
func IsTemporaryError(err error) bool {
	var e *Error
	if errors.As(err, &e) {
		return e.Code == http.StatusTooManyRequests ||
			(e.Code >= 500 && e.Code <= 599) ||
			e.Is(ErrTooManyRequests)
	}
	return false
}