#include <doctest/doctest.h>

#include <vector>

#include "packeteer/l7/tftp.hpp"

using namespace packeteer::net;

namespace {

std::vector<unsigned char> build_rrq(const std::string& filename, const std::string& mode) {
    std::vector<unsigned char> bytes = {0x00, 0x01};  // opcode RRQ
    bytes.insert(bytes.end(), filename.begin(), filename.end());
    bytes.push_back(0);
    bytes.insert(bytes.end(), mode.begin(), mode.end());
    bytes.push_back(0);
    return bytes;
}

}  // namespace

TEST_CASE("parse_tftp decodes an RRQ with filename and mode") {
    auto msg = parse_tftp(build_rrq("boot.img", "octet"));
    REQUIRE(msg.has_value());
    CHECK(msg->opcode == kTftpRrq);
    REQUIRE(msg->filename.has_value());
    CHECK(*msg->filename == "boot.img");
    REQUIRE(msg->mode.has_value());
    CHECK(*msg->mode == "octet");
}

TEST_CASE("parse_tftp decodes a DATA block number") {
    std::vector<unsigned char> bytes = {0x00, 0x03, 0x00, 0x07, 'h', 'i'};
    auto msg = parse_tftp(bytes);
    REQUIRE(msg.has_value());
    CHECK(msg->opcode == kTftpData);
    REQUIRE(msg->block.has_value());
    CHECK(*msg->block == 7);
}

TEST_CASE("parse_tftp decodes an ACK block number") {
    std::vector<unsigned char> bytes = {0x00, 0x04, 0x00, 0x07};
    auto msg = parse_tftp(bytes);
    REQUIRE(msg.has_value());
    CHECK(msg->opcode == kTftpAck);
    REQUIRE(msg->block.has_value());
    CHECK(*msg->block == 7);
}

TEST_CASE("parse_tftp decodes an ERROR code and message") {
    std::vector<unsigned char> bytes = {0x00, 0x05, 0x00, 0x01};
    std::string message = "File not found";
    bytes.insert(bytes.end(), message.begin(), message.end());
    bytes.push_back(0);

    auto msg = parse_tftp(bytes);
    REQUIRE(msg.has_value());
    CHECK(msg->opcode == kTftpError);
    REQUIRE(msg->error_code.has_value());
    CHECK(*msg->error_code == 1);
    REQUIRE(msg->error_message.has_value());
    CHECK(*msg->error_message == "File not found");
}

TEST_CASE("parse_tftp rejects an opcode outside the known range") {
    std::vector<unsigned char> bytes = {0x00, 0x99};
    CHECK_FALSE(parse_tftp(bytes).has_value());
}

TEST_CASE("parse_tftp handles an RRQ with a truncated filename gracefully") {
    std::vector<unsigned char> bytes = {0x00, 0x01, 'a', 'b'};  // no null terminator
    auto msg = parse_tftp(bytes);
    REQUIRE(msg.has_value());
    CHECK(msg->opcode == kTftpRrq);
    CHECK_FALSE(msg->filename.has_value());
}

TEST_CASE("TftpDissector claims port 69 and formats an RRQ") {
    TftpDissector dissector;
    CHECK(dissector.port() == kTftpPort);

    auto summary = dissector.summarize(build_rrq("boot.img", "octet"));
    REQUIRE(summary.has_value());
    CHECK(*summary == "TFTP RRQ boot.img (octet)");
}