package jsonrpc2

import (
	"context"
	"maps"
)

type ctxKeyMeta int

// WithMeta returns a Context where the given key will be set to the given value
// in the Meta field of all JSONRPC2 requests made using Clients from this
// package.
func WithMeta(ctx context.Context, key string, value any) context.Context {
	m, _ := ctx.Value(ctxKeyMeta(0)).(map[string]any)
	if m == nil {
		m = map[string]any{}
	} else {
		m = maps.Clone(m)
	}

	m[key] = value
	return context.WithValue(ctx, ctxKeyMeta(0), m)
}

// GetMeta returns all key/values which have been set on the Context using
// WithMeta. This may return nil if WithMeta was never called.
func GetMeta(ctx context.Context) map[string]any {
	m, _ := ctx.Value(ctxKeyMeta(0)).(map[string]any)
	return m
}