From 598865d216158b4f9c37a3836297081e07cea547 Mon Sep 17 00:00:00 2001
From: zanostro <zan.skvarca@gmail.com>
Date: Mon, 17 Nov 2025 13:45:03 +0100
Subject: [PATCH] added loading

---
 simulator_SIC_XE/include/file_reader.h |  1 +
 simulator_SIC_XE/include/loader.h      |  3 +
 simulator_SIC_XE/src/file_reader.cpp   |  1 +
 simulator_SIC_XE/src/loader.cpp        | 82 +++++++++++++++++++++++++-
 4 files changed, 86 insertions(+), 1 deletion(-)

diff --git a/simulator_SIC_XE/include/file_reader.h b/simulator_SIC_XE/include/file_reader.h
index e2da87a..87b8a17 100644
--- a/simulator_SIC_XE/include/file_reader.h
+++ b/simulator_SIC_XE/include/file_reader.h
@@ -11,6 +11,7 @@ public:
     ~FileReader() override;
 
     int readByte() override;
+
     bool readBytes(uint8_t* buf, size_t len) override;
     std::string readString(size_t len) override;
     std::string readLine() override;
diff --git a/simulator_SIC_XE/include/loader.h b/simulator_SIC_XE/include/loader.h
index c4d75e3..16ffa45 100644
--- a/simulator_SIC_XE/include/loader.h
+++ b/simulator_SIC_XE/include/loader.h
@@ -51,6 +51,9 @@ private :
     string _filename;
     shared_ptr<FileReader> _file_reader;
     HeaderMetadata readHeader();
+    TextRecord readTextRecord();
+    EndRecord readEndRecord();
+    bool load_into_memory(int start_address, const std::vector<uint8_t>& data);
 
 };
 
diff --git a/simulator_SIC_XE/src/file_reader.cpp b/simulator_SIC_XE/src/file_reader.cpp
index 0ace74b..2a800cc 100644
--- a/simulator_SIC_XE/src/file_reader.cpp
+++ b/simulator_SIC_XE/src/file_reader.cpp
@@ -12,6 +12,7 @@ int FileReader::readByte() {
     return static_cast<unsigned char>(c);
 }
 
+
 bool FileReader::readBytes(uint8_t* buf, size_t len) {
     in.read(reinterpret_cast<char*>(buf), static_cast<std::streamsize>(len));
     return static_cast<size_t>(in.gcount()) == len;
diff --git a/simulator_SIC_XE/src/loader.cpp b/simulator_SIC_XE/src/loader.cpp
index 0626ac6..df459fa 100644
--- a/simulator_SIC_XE/src/loader.cpp
+++ b/simulator_SIC_XE/src/loader.cpp
@@ -1,5 +1,7 @@
 #include "loader.h"
 #include "file_reader.h"
+#include "machine.h"
+#include "constants.h"
 
 Loader::~Loader()
 {
@@ -11,8 +13,28 @@ Loader::~Loader()
 
 void Loader::load()
 {
+    HeaderMetadata header = readHeader();
       
-
+    while(true) {
+        RecordType type = parseRecordType(static_cast<char>(_file_reader->readByte()));
+        switch (type) {
+            case RecordType::TEXT: {
+                TextRecord textRecord = readTextRecord();
+                if (!load_into_memory(textRecord.start_address, textRecord.data)) {
+                    throw std::runtime_error("Failed to load text record into memory");
+                }
+                break;
+            }
+            case RecordType::END: {
+                EndRecord endRecord = readEndRecord();
+                _machine->setPC(endRecord.execution_start_address);
+                return; // Loading complete
+            }
+            case RecordType::UNKNOWN:
+            default:
+                throw std::runtime_error("Unknown record type encountered");
+        }
+    }
 }
 
 Loader::RecordType Loader::parseRecordType(char c)
@@ -32,4 +54,62 @@ Loader::HeaderMetadata Loader::readHeader()
         throw std::runtime_error("Expected HEADER record");
     }
     HeaderMetadata header;
+    // Read program name (6 bytes)
+    header.program_name = _file_reader->readString(6);
+    // Read start address (6 hex digits)
+    header.start_address = std::stoi(_file_reader->readString(6), nullptr, 16);
+    // Read length (6 hex digits)
+    header.length = std::stoi(_file_reader->readString(6), nullptr, 16);
+    // consume newline
+    _file_reader->readLine();
+    return header;
+}
+
+Loader::TextRecord Loader::readTextRecord()
+{
+    TextRecord record;
+    // Assume 'T' has already been read
+    record.start_address = std::stoi(_file_reader->readString(6), nullptr, 16);
+    // Read length (1 byte, 2 hex digits)
+    int length = std::stoi(_file_reader->readString(2), nullptr, 16);
+
+    // Read data bytes
+    record.data.resize(length);
+    
+
+    for(int i = 0; i < length; ++i) {
+        unsigned char buffer[2];
+        _file_reader->readBytes(buffer, 2);
+        record.data[i] = static_cast<uint8_t>(std::stoi(std::string(reinterpret_cast<char*>(buffer), 2), nullptr, 16));
+    }
+    // consume newline
+    _file_reader->readLine();
+
+}
+
+Loader::EndRecord Loader::readEndRecord()
+{
+    EndRecord record;
+    // Assume 'E' has already been read
+    std::string addrStr = _file_reader->readString(6);
+    if (!addrStr.empty()) {
+        record.execution_start_address = std::stoi(addrStr, nullptr, 16);
+    } else {
+        record.execution_start_address = 0; // default start address
+    }
+    // consume newline
+    _file_reader->readLine();
+    return record;
+}
+
+bool Loader::load_into_memory(int start_address, const std::vector<uint8_t> &data)
+{
+    for(size_t i = 0; i < data.size(); ++i) {
+        int addr = start_address + static_cast<int>(i);
+        if (addr < 0 || addr >= MEMORY_SIZE) { // 24-bit address space
+            return false; // Address out of bounds
+        }
+        _machine->setByte(addr, data[i]);
+    }
+    return true;
 }