chore: prepare docfill project for gitea

internal/docfill/errors.go

@@ -0,0 +1,74 @@
+package docfill
+
+type ErrorCode string
+
+const (
+	CodeCLIUsage             ErrorCode = "CLI_USAGE"
+	CodeConfigRead           ErrorCode = "CONFIG_READ"
+	CodeConfigParse          ErrorCode = "CONFIG_PARSE"
+	CodeConfigValidate       ErrorCode = "CONFIG_VALIDATE"
+	CodeDataExcel            ErrorCode = "DATA_EXCEL"
+	CodeDataSQLite           ErrorCode = "DATA_SQLITE"
+	CodeDataEmpty            ErrorCode = "DATA_EMPTY"
+	CodeDataFilterField      ErrorCode = "DATA_FILTER_FIELD"
+	CodeDataFilterValue      ErrorCode = "DATA_FILTER_VALUE"
+	CodeDataFilterNoMatch    ErrorCode = "DATA_FILTER_NO_MATCH"
+	CodeDataFilterMultiMatch ErrorCode = "DATA_FILTER_MULTI_MATCH"
+	CodeTemplateOpen         ErrorCode = "TEMPLATE_OPEN"
+	CodeTemplateFieldMissing ErrorCode = "TEMPLATE_FIELD_MISSING"
+	CodeTemplateUnresolved   ErrorCode = "TEMPLATE_UNRESOLVED"
+	CodeOutputExists         ErrorCode = "OUTPUT_EXISTS"
+	CodeOutputWrite          ErrorCode = "OUTPUT_WRITE"
+	CodeInternal             ErrorCode = "INTERNAL"
+)
+
+type AppError struct {
+	Code    ErrorCode
+	Message string
+	Hint    string
+	Context map[string]string
+	Cause   error
+}
+
+func (e *AppError) Error() string {
+	if e == nil {
+		return ""
+	}
+	if e.Cause == nil {
+		return e.Message
+	}
+	return e.Message + ": " + e.Cause.Error()
+}
+
+func (e *AppError) Unwrap() error {
+	if e == nil {
+		return nil
+	}
+	return e.Cause
+}
+
+func appError(code ErrorCode, message string) *AppError {
+	return &AppError{
+		Code:    code,
+		Message: message,
+		Context: make(map[string]string),
+	}
+}
+
+func (e *AppError) withHint(hint string) *AppError {
+	e.Hint = hint
+	return e
+}
+
+func (e *AppError) withCause(cause error) *AppError {
+	e.Cause = cause
+	return e
+}
+
+func (e *AppError) withContext(key, value string) *AppError {
+	if e.Context == nil {
+		e.Context = make(map[string]string)
+	}
+	e.Context[key] = value
+	return e
+}