package configkit

import (
	"io"

	"go.maximumdirect.net/configkit/internal/engine"
)

// LoadError reports safe structured diagnostics for a failed configuration load.
// It intentionally does not expose or unwrap parser and application errors.
type LoadError struct{ value *engine.LoadError }

// Error implements error without rendering diagnostic messages or input values.
func (e *LoadError) Error() string {
	if e == nil || e.value == nil {
		return "configkit: configuration load failed"
	}
	return e.value.Error()
}

// Diagnostics returns a deep copy of the error's canonical diagnostics.
func (e *LoadError) Diagnostics() []Diagnostic {
	if e == nil || e.value == nil {
		return nil
	}
	values := e.value.Diagnostics()
	if values == nil {
		return nil
	}
	result := make([]Diagnostic, len(values))
	for i := range values {
		result[i] = fromEngineDiagnostic(values[i])
	}
	return result
}

// Sources returns a deep copy of sources discovered before loading failed.
func (e *LoadError) Sources() []SourceInfo {
	if e == nil || e.value == nil {
		return nil
	}
	values := e.value.Sources()
	if values == nil {
		return nil
	}
	result := make([]SourceInfo, len(values))
	for i := range values {
		result[i] = fromEngineSourceInfo(values[i])
	}
	return result
}

// Source returns a detached record from the sanitized source evidence retained
// before loading failed, including placement evidence available at that point.
// IDs are local to the failed load. It does not acquire sources or access the
// filesystem. Empty or unknown IDs return false.
func (e *LoadError) Source(id string) (SourceInfo, bool) {
	if e == nil || e.value == nil {
		return SourceInfo{}, false
	}
	value, ok := e.value.Source(id)
	if !ok {
		return SourceInfo{}, false
	}
	return fromEngineSourceInfo(value), true
}

// WriteDiagnostics writes diagnostics in canonical order. It escapes terminal
// control characters and propagates writer errors, including short writes.
func WriteDiagnostics(output io.Writer, diagnostics []Diagnostic) error {
	return engine.WriteDiagnostics(output, toEngineDiagnostics(diagnostics))
}