errors.go

package cql2

import (
	"fmt"
	"strings"
)

// SyntaxError is returned when input cannot be parsed.
type SyntaxError struct {
	Encoding Encoding
	At       Pos
	Snippet  string
	Msg      string
	Got      string
	Expected []string
}

func (e *SyntaxError) Error() string {
	var b strings.Builder
	switch e.Encoding {
	case EncodingJSON:
		b.WriteString("json")
	default:
		b.WriteString("text")
	}
	if e.At != (Pos{}) {
		fmt.Fprintf(&b, ":%s", e.At.String())
	}
	b.WriteString(": ")
	if e.Msg != "" {
		b.WriteString(e.Msg)
	} else {
		b.WriteString("syntax error")
	}
	if e.Got != "" {
		fmt.Fprintf(&b, " (got %q", e.Got)
		if len(e.Expected) > 0 {
			fmt.Fprintf(&b, ", expected one of: %s", strings.Join(e.Expected, ", "))
		}
		b.WriteByte(')')
	} else if len(e.Expected) > 0 {
		fmt.Fprintf(&b, " (expected one of: %s)", strings.Join(e.Expected, ", "))
	}
	if e.Snippet != "" {
		fmt.Fprintf(&b, " near %q", e.Snippet)
	}
	return b.String()
}

// ConformanceError is returned when input requires a conformance class
// that is not enabled in the active configuration.
type ConformanceError struct {
	Required Conformance
	Active   Conformance
	Feature  string
	At       Pos
}

func (e *ConformanceError) Error() string {
	var b strings.Builder
	b.WriteString("conformance error")
	if e.At != (Pos{}) {
		fmt.Fprintf(&b, " at %s", e.At.String())
	}
	if e.Feature != "" {
		fmt.Fprintf(&b, ": feature %q", e.Feature)
	}
	fmt.Fprintf(&b, ": required=0x%x active=0x%x", uint32(e.Required), uint32(e.Active))
	return b.String()
}

// GeometryError is returned for malformed WKT or GeoJSON geometry.
type GeometryError struct {
	Encoding Encoding
	At       Pos
	Msg      string
}

func (e *GeometryError) Error() string {
	var b strings.Builder
	switch e.Encoding {
	case EncodingJSON:
		b.WriteString("geojson")
	default:
		b.WriteString("wkt")
	}
	if e.At != (Pos{}) {
		fmt.Fprintf(&b, ":%s", e.At.String())
	}
	b.WriteString(": ")
	if e.Msg != "" {
		b.WriteString(e.Msg)
	} else {
		b.WriteString("invalid geometry")
	}
	return b.String()
}

// UnliftableError is returned when a Go value cannot be lifted to a Node.
type UnliftableError struct {
	Value any
	Msg   string
}

func (e *UnliftableError) Error() string {
	if e.Msg != "" {
		return fmt.Sprintf("cannot lift %T: %s", e.Value, e.Msg)
	}
	return fmt.Sprintf("cannot lift %T", e.Value)
}

// ValidationError is returned by Validate when an AST is structurally
// well-formed (parsed without error) but violates spec arity or shape
// constraints — for example a comparison op with three args, or IN
// whose RHS is not an ArrayLit.
type ValidationError struct {
	// Op is set when the violation is on an *Op node; empty otherwise.
	Op Operator
	// Function is set when the violation is on a *FunctionCall node.
	Function string
	// Msg is a human-readable description of the violation.
	Msg string
	// Node is the offending AST node.
	Node Node
}

func (e *ValidationError) Error() string {
	switch {
	case e.Op != "":
		return fmt.Sprintf("validation: operator %q: %s", string(e.Op), e.Msg)
	case e.Function != "":
		return fmt.Sprintf("validation: function %q: %s", e.Function, e.Msg)
	default:
		return fmt.Sprintf("validation: %s", e.Msg)
	}
}