// Example 02 — Named Ports
//
// A three-stage text pipeline where port names carry semantic meaning:
//
//  [tokenise] --"words"--> [count_words] --"count"--> [report]
//                                         --"words"--> [report]
//
// Named ports let the connect() call read like documentation:
//   connect("tok", tok.output<"words">(), "cnt", cnt.input<"words">())
// A typo in the name is a compile-time error, not a runtime surprise.

#include <kpn/kpn.hpp>
#include <chrono>
#include <iostream>
#include <sstream>
#include <string>
#include <thread>
#include <tuple>
#include <vector>

// ── Node functions ────────────────────────────────────────────────────────────

static int sentence_index = 0;

static std::vector<std::string> tokenise() {
    static const char* sentences[] = {
        "the quick brown fox jumps over the lazy dog",
        "kahn process networks are a model of concurrent computation",
        "each node runs in its own thread communicating via channels",
        "named ports catch wiring mistakes at compile time",
    };
    std::istringstream ss(sentences[sentence_index++ % 4]);
    std::vector<std::string> words;
    std::string w;
    while (ss >> w) words.push_back(w);
    std::this_thread::sleep_for(std::chrono::milliseconds(50));
    return words;
}

// Returns (word_count, original_words) — two outputs via tuple
static std::tuple<int, std::vector<std::string>>
count_words(std::vector<std::string> words) {
    return {static_cast<int>(words.size()), std::move(words)};
}

static void report(int count, std::vector<std::string> words) {
    std::cout << "[" << count << " words] ";
    for (auto& w : words) std::cout << w << ' ';
    std::cout << '\n';
}

// ── main ──────────────────────────────────────────────────────────────────────

int main() {
    using namespace kpn;

    // --8<-- [start:named_port_creation]
    // tokenise: no inputs, one named output "words"
    auto tok = make_node<tokenise>(out<"words">{}, 4);

    // count_words: named input "words", named outputs "count" and "words"
    auto cnt = make_node<count_words>(in<"words">{}, out<"count", "words">{}, 4);

    // report: two named inputs
    auto snk = make_node<report>(in<"count", "words">{}, 4);
    // --8<-- [end:named_port_creation]

    // --8<-- [start:named_port_network]
    Network net;
    net.add("tok", tok)
       .add("cnt", cnt)
       .add("snk", snk)
       .connect("tok", tok.template output<"words">(), "cnt", cnt.template input<"words">())
       .connect("cnt", cnt.template output<"count">(), "snk", snk.template input<"count">())
       .connect("cnt", cnt.template output<"words">(), "snk", snk.template input<"words">())
       .build();

    net.start();
    std::this_thread::sleep_for(std::chrono::milliseconds(500));
    net.stop();
    // --8<-- [end:named_port_network]
}