package re3lib;

import java.io.File;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;

import ghidra.app.script.GhidraScript;
import ghidra.program.model.address.Address;
import ghidra.program.model.listing.Function;

public class FunctionDatabase {
  public enum Type {
    Auto,
    Fix,
    Stub
  }

  public class Dependency implements java.io.Serializable {
    private static final long serialVersionUID = 1L;
    public Address address;
    public String name;

    public Dependency(Address address, String name) {
      this.address = address;
      this.name = name;
    }

    private void writeObject(java.io.ObjectOutputStream out) throws java.io.IOException {
      out.writeObject(address != null ? address.toString() : null);
      out.writeObject(name);
    }

    private void readObject(java.io.ObjectInputStream in) throws java.io.IOException, ClassNotFoundException {
      String addressString = (String) in.readObject();
      if (addressString != null) {
        address = RecompileConfig.INSTANCE.script.getCurrentProgram().getAddressFactory().getAddress(addressString);
      }
      name = (String) in.readObject();
    }
  }

  public class Entry implements java.io.Serializable {
    private static final long serialVersionUID = 1L;
    public Address address;
    public String name;
    public File file;
    public Type type;
    public List<Dependency> dependencies = new ArrayList<>();

    private void writeObject(java.io.ObjectOutputStream out) throws java.io.IOException {
      out.writeObject(address != null ? address.toString() : null);
      out.writeObject(name);
      out.writeObject(file != null ? file.toString() : null);
      out.writeObject(type);
      out.writeObject(dependencies);
    }

    private void readObject(java.io.ObjectInputStream in) throws java.io.IOException, ClassNotFoundException {
      String addressString = (String) in.readObject();
      if (addressString != null) {
        address = RecompileConfig.INSTANCE.script.getCurrentProgram().getAddressFactory().getAddress(addressString);
      }
      name = (String) in.readObject();
      String fileString = (String) in.readObject();
      if (fileString != null) {
        file = new File(fileString);
      }
      type = (Type) in.readObject();
      dependencies = (List<Dependency>) in.readObject();
    }
  }

  public List<Entry> entries = new ArrayList<>();
  private File file;
  private transient GhidraScript script;

  public FunctionDatabase(GhidraScript script) {
    this.script = script;
    file = new File(RecompileConfig.INSTANCE.outputDir, "functions.dat");
  }

  public void load() throws Exception {
    if (!file.exists()) {
      return;
    }

    try (java.io.ObjectInputStream ois = new java.io.ObjectInputStream(new java.io.FileInputStream(file))) {
      entries = (List<Entry>) ois.readObject();
      script.println("Loaded " + entries.size() + " function entries from " + file);
    } catch (java.io.IOException | ClassNotFoundException e) {
      script.println("Error loading function database: " + e.getMessage());
    }
  }

  public void save() throws Exception {
    try (java.io.ObjectOutputStream oos = new java.io.ObjectOutputStream(new java.io.FileOutputStream(file))) {
      oos.writeObject(entries);
      script.println("Saved " + entries.size() + " function entries to " + file);
    } catch (java.io.IOException e) {
      script.println("Error saving function database: " + e.getMessage());
    }
  }

  public void add(Entry entry) {
    entries.add(entry);
  }

  public void applyDefaultFilters(boolean rebuildAllGlobals) throws Exception {
    GlobalDumper globalDumper = new GlobalDumper(script);
    FunctionDumper dumper = new FunctionDumper(script, globalDumper);

    if (rebuildAllGlobals) {
      globalDumper.removeGlobalManifest();
    }

    boolean madeAnyChanges = false;

    // Create a hash map to store symbol names
    Map<Address, String> symbolNames = new HashMap<>();
    Map<String, File> exportedFunctionNames = new HashMap<>();
    for (Entry entry : entries) {
      Function function = script.getFunctionAt(entry.address);
      if (function != null) {
        String dirComponent = entry.file.getParent().toString();
        boolean isAuto = entry.type == Type.Auto;
        boolean isFix = entry.type == Type.Fix;
        // Get the actual symbol name and store it in the hash map
        String symbolName = function.getName();
        symbolNames.put(entry.address, symbolName);

        if (isAuto && !exportedFunctionNames.containsKey(entry.name)) {
          exportedFunctionNames.put(entry.name, entry.file);
        } else if (isFix) {
          exportedFunctionNames.replace(entry.name, entry.file);
        }
      }
    }

    // Print the number of symbol names collected
    script.println("Collected " + symbolNames.size() + " symbol names");

    boolean dryMode = false;

    HashSet<Function> functionsToRegenerate = new HashSet<>();

    Iterator<Entry> iterator = entries.iterator();
    while (iterator.hasNext()) {
      Entry entry = iterator.next();
      Function function = script.getFunctionAt(entry.address);

      boolean pendingDelete = false;
      boolean pendingRegenerate = false;

      if (rebuildAllGlobals) {
        pendingRegenerate = true;
      }

      // Remove CRT and other blacklisted functions
      if (function == null || !dumper.isValidFunction(function)) {
        // Remove the file
        if (entry.file != null && entry.file.exists()) {
          script.println("Removed file: " + entry.file.getAbsolutePath());
          pendingDelete = true;
        }

        // Remove entry from the list
        script.println("Removed invalid function entry: " + entry.name + " at " + entry.address);
        function = null;
      }

      // Check if symbol name matches the symbol name parsed from the file
      if (function != null) {
        String actualSymbolName = symbolNames.get(entry.address);
        if (actualSymbolName == null) {
          throw new Exception(
              "Symbol name not found for function at " + entry.address + " in file " + entry.file.getAbsolutePath());
        }

        if (actualSymbolName != null && !actualSymbolName.equals(entry.name)) {
          File fnExportedFile = exportedFunctionNames.get(entry.name);
          if (fnExportedFile != null && fnExportedFile != entry.file) {
            // Already exists elsewhere, so remove this file
            script.println("Removing duplicate function: " + entry.name + " at " + entry.address + " overridden by "
                + fnExportedFile);
            pendingDelete = true;
          } else {
            // Regeneral this function
            script.println("Symbol name mismatch for function at " + entry.address + ": " +
                "File name: " + entry.name + ", Actual symbol: " + actualSymbolName);
            entry.name = actualSymbolName; // Update the entry name to match the actual symbol
            pendingRegenerate = true;
          }
        }

        // Check if dependencies are valid
        for (Dependency dependency : entry.dependencies) {
          Function depFunction = script.getFunctionAt(dependency.address);
          if (depFunction == null) {
            script.println(
                "Dependency not found: " + dependency.name + " at " + dependency.address + " in " + entry.file);
            pendingRegenerate = true;
          } else if (!dumper.isValidFunction(depFunction) || !depFunction.getName().equals(dependency.name)) {
            script
                .println("Invalid dependency: " + dependency.name + " at " + dependency.address + " in " + entry.file
                    + " should be " + dependency.name);
            pendingRegenerate = true;
          }
        }

        entry.name = actualSymbolName; // Update the entry name to match the actual symbol
        madeAnyChanges = true;
      }

      if (pendingDelete) {
        iterator.remove();
        if (!dryMode) {
          entry.file.delete();
          madeAnyChanges = true;
        }
      } else if (pendingRegenerate && entry.type != Type.Stub) {
        if (!dryMode) {
          functionsToRegenerate.add(function);
          madeAnyChanges = true;
        }
      }
    }

    for (Function function : functionsToRegenerate) {
      script.println("Regenerating function: " + function.getName() + " at " + function.getEntryPoint());
      dumper.dump(function);
    }

    if (madeAnyChanges) {
      // Update CMake timestamp
      RecompileConfig.INSTANCE.touchCMakeTimestamp();
      globalDumper.dumpGlobals();
      globalDumper.saveGlobalManifest();

      TypeDumper typeDumper = new TypeDumper(script);
      typeDumper.run();
    }
  }
}