package main

import (
	"bufio"
	"encoding/json"
	"io"
	"testing"
	"time"

	stdio "git.novox.be/novox/mesh-sdk/go"
)

// whoCalled serves one tool that answers callerOf of its arguments, over the SDK's stdio loop as the runtime
// launches a bundle, and sends it one call with params.
func whoCalled(t *testing.T, params map[string]any) string {
	t.Helper()
	inR, inW := io.Pipe()
	outR, outW := io.Pipe()
	go func() {
		_ = stdio.ServeOn("mesh-knowledge", []stdio.Tool{{Name: "who", Run: func(args map[string]any) (any, error) {
			return callerOf(args), nil
		}}}, inR, outW)
	}()
	defer inW.Close()
	b, _ := json.Marshal(map[string]any{"jsonrpc": "2.0", "id": 1, "method": "tools/call", "params": params})
	_, _ = inW.Write(append(b, '\n'))
	got := make(chan string, 1)
	go func() {
		lines := bufio.NewScanner(outR)
		if lines.Scan() {
			var m struct {
				Result struct {
					Content []struct {
						Text string `json:"text"`
					} `json:"content"`
				} `json:"result"`
			}
			_ = json.Unmarshal(lines.Bytes(), &m)
			var who string
			if len(m.Result.Content) > 0 {
				_ = json.Unmarshal([]byte(m.Result.Content[0].Text), &who)
			}
			got <- who
		}
	}()
	select {
	case who := <-got:
		return who
	case <-time.After(3 * time.Second):
		t.Fatal("the call was not answered")
		return ""
	}
}

// **Who called is the caller the runtime proved** (hq issue 365): read from the call's runtime-written `_meta`,
// never from its arguments; Unproven where the runtime named none.
func TestTheCallerIsTheOneTheRuntimeProved(t *testing.T) {
	if got := whoCalled(t, map[string]any{"name": "who", "arguments": map[string]any{"caller": "novox.node-tools"},
		"_meta": map[string]any{stdio.MetaCaller: "shanks.node-tools"}}); got != "shanks.node-tools" {
		t.Errorf("callerOf answered %q, want the runtime's caller", got)
	}
	if got := whoCalled(t, map[string]any{"name": "who", "arguments": map[string]any{"caller": "novox.node-tools"}}); got != Unproven {
		t.Errorf("a call the runtime named no caller for answered %q, want %s", got, Unproven)
	}
}