#include <iostream>
#include <iomanip>
#include <memory>
#include <vector>
#include <cstddef>

#include "dbc_parser.h"
#include "dbc_tree_builder.h"
#include "dbc_decode_builder.h"
#include "dbc_decoder.h"

static void PrintTree (const TreeNode *node, int indent) {
  if (node == nullptr)
    return;

  for (int i = 0; i < indent; ++i)
    std::cout << "  ";

  switch (node->GetType()) {
    case NodeType::Root:
      std::cout << "[root] " << node->GetName() << "\n";
      break;

    case NodeType::Frame: {
      const FrameInfo *frame = node->GetFrame();
      std::cout << "[frame] " << node->GetName();

      if (frame != nullptr) {
        std::cout << " id=0x" << std::hex << frame->canId << std::dec
                  << " ext=" << (frame->isExtended ? "yes" : "no")
                  << " dlc=" << static_cast<unsigned int> (frame->dlc);

        if (frame->hasPgn)
          std::cout << " pgn=" << frame->pgn;
      }

      std::cout << "\n";
      break;
    }

    case NodeType::Signal: {
      const SignalInfo *signal = node->GetSignal();
      std::cout << "[signal] " << node->GetName();

      if (signal != nullptr) {
        std::cout << " start=" << signal->startBit
                  << " len=" << signal->length
                  << " unit=" << signal->unit;
      }

      std::cout << "\n";
      break;
    }

    default:
      std::cout << "[unknown]\n";
      break;
  }

  for (std::size_t i = 0U; i < node->GetChildCount(); ++i)
    PrintTree (node->GetChild (i), indent + 1);
}

static void PrintDecodedFrame (const DecodedFrameValue &decoded) {
  if (!decoded.valid || (decoded.definition == nullptr)) {
    std::cout << "No frame definition found.\n";
    return;
  }

  std::cout << "Decoded frame: " << decoded.definition->name << "\n";

  for (std::size_t index = 0U; index < decoded.signals.size(); ++index) {
    const DecodedSignalValue &signal = decoded.signals[index];

    if ((signal.definition == nullptr) || !signal.valid)
      continue;

    std::cout << "  " << signal.definition->name
              << " raw=" << signal.rawValue
              << " physical=" << signal.physicalValue
              << " " << signal.definition->unit
              << "\n";
  }
}

int main (int argc, char *argv[]) {
  if (argc < 2) {
    std::cerr << "Usage: dbc_demo <file.dbc>\n";
    return 1;
  }

  try {
    DbcParser parser;
    DbcDatabase database = parser.ParseFile (argv[1]);

    DbcTreeBuilder treeBuilder;
    std::unique_ptr<TreeNode> root = treeBuilder.Build (database);

    std::cout << "=== Parsed tree ===\n";
    PrintTree (root.get(), 0);

    DbcDecodeBuilder decodeBuilder;
    DecodeDatabase decodeDatabase = decodeBuilder.Build (database);

    /*
     * Example raw frame.
     * Replace with live CAN frame or trace record later.
     */
    RawCanFrame rawFrame;
    rawFrame.canId = decodeDatabase.frames.empty() ? 0U : decodeDatabase.frames[0].canId;
    rawFrame.isExtended = decodeDatabase.frames.empty() ? false : decodeDatabase.frames[0].isExtended;
    rawFrame.data.resize (8U, 0U);

    DbcDecoder decoder;
    DecodedFrameValue decoded = decoder.Decode (decodeDatabase, rawFrame);

    std::cout << "\n=== Decoded frame ===\n";
    PrintDecodedFrame (decoded);
  } catch (const std::exception &ex) {
    std::cerr << "Error: " << ex.what() << "\n";
    return 2;
  }

  return 0;
}