From 4e56134dd9b1774d0e97841d2b977599659e3da9 Mon Sep 17 00:00:00 2001
From: Torrie Fischer <torrie@ripple.com>
Date: Mon, 11 Dec 2023 07:57:22 +0100
Subject: [PATCH] inputs: serial: implement a CLI

---
 src/inputs/Serial.cpp | 182 +++++++++++++++++++++++++++++++++++++-----
 src/inputs/Serial.h   |  54 ++++++++++++-
 2 files changed, 210 insertions(+), 26 deletions(-)

diff --git a/src/inputs/Serial.cpp b/src/inputs/Serial.cpp
index 2358665..bc30a66 100644
--- a/src/inputs/Serial.cpp
+++ b/src/inputs/Serial.cpp
@@ -1,33 +1,171 @@
 #include "Serial.h"
+#include "../Static.h"
+#include <LittleFS.h>
+#include "../Config.h"
+#include "../Sequencer.h"
 
-InputEvent
-Serial::read()
+SerialInput::SerialInput() : InputSource("Serial"),
+  m_state(ParseState::Normal),
+  m_logPrinter(this)
 {
-  while (Serial.available() > 0) {
-    char nextChar = Serial.read();
-    if (nextChar == '\n') {
-      doCommand();
-      m_buf = "";
-    } else {
-      m_buf += nextChar;
-    }
-  }
 }
 
 void
-Serial::doCommand() {
-  if (command == "tasks") {
-    Serial.println("Tasks:");
-    auto sched = MainLoop::instance()->scheduler;
-    for(auto task : sched.tasks) {
-        bool isFigment = task->isFigment();
-        if (isFigment) {
-          Serial.println("F " + task->name);
-        } else {
-          Serial.println("T " + task->name);
-        }
+SerialInput::redrawPrompt()
+{
+  if (m_canRedraw) {
+    Serial.print((char)8);
+    Serial.print((char)27);
+    Serial.print("[2K");
+    Serial.print((char)8);
+    Serial.print((char)27);
+    Serial.print("[G");
+    Serial.print('\r');
+    Serial.print("> ");
+    Serial.print(m_buf);
+  }
+}
+
+InputEvent
+SerialInput::parseNormal(char nextChar)
+{
+  if (nextChar == 27) {
+    m_state = ParseState::EscapeSequence;
+    return InputEvent::None;
+  }
+
+  if (nextChar == 13) {
+    redrawPrompt();
+    Serial.println();
+    if (m_buf.length() > 0) {
+      m_canRedraw = false;
+      doCommand();
+      m_canRedraw = true;
+      m_history.insert(m_buf);
+      m_buf = "";
+    }
+    m_historyOffset = 0;
+    redrawPrompt();
+    return InputEvent{};
+  }
+  
+  if (nextChar == 8) {
+    if (m_buf.length() > 0) {
+      m_buf.remove(m_buf.length() - 1, 1);
+    }
+    Serial.print((char)8);
+    Serial.print((char)27);
+    Serial.print("[K");
+    redrawPrompt();
+    return InputEvent::None;
+  }
+  
+  if (nextChar >= 32 && nextChar <= 126) {
+    m_buf += nextChar;
+    Serial.print(nextChar);
+  }
+  return InputEvent::None;
+}
+
+InputEvent
+SerialInput::parseEscape(char nextChar)
+{
+  if (nextChar == '[') {
+    m_state = ParseState::CSI;
+  } else {
+    m_state = ParseState::Normal;
+  }
+  return InputEvent::None;
+}
+
+InputEvent
+SerialInput::parseCSI(char nextChar)
+{
+  if (nextChar == 'A') {
+    if (m_historyOffset < m_history.size()) {
+      m_historyOffset += 1;
+      m_buf = m_history.peek(m_historyOffset);
+      redrawPrompt();
+    } else {
+      Serial.print((char)7);
+    }
+  } else if (nextChar == 'B') {
+    if (m_historyOffset > 0) {
+      m_historyOffset -= 1;
+      m_buf = m_history.peek(m_historyOffset);
+      redrawPrompt();
+    } else {
+      Serial.print((char)7);
+    }
+  } else {
+    Serial.print((char)7);
+  }
+  m_state = ParseState::Normal;
+  return InputEvent::None;
+}
+
+InputEvent
+SerialInput::read()
+{
+  while (Serial.available() > 0) {
+    char nextChar = Serial.read();
+    InputEvent ret = InputEvent::None;
+    switch (m_state) {
+      case ParseState::Normal:
+        ret = parseNormal(nextChar);break;
+      case ParseState::EscapeSequence:
+        ret = parseEscape(nextChar);break;
+      case ParseState::CSI:
+        ret = parseCSI(nextChar);break;
+    }
+    if (ret != InputEvent::None) {
+        return ret;
     }
   }
+  return InputEvent::None;
+}
+
+void
+doHelp(Args& args, Print& out)
+{
+  out.println("Available commands:");
+  auto sched = MainLoop::instance()->scheduler;
+  for(auto task : sched.tasks) {
+    for(auto &command : task->commands()) {
+      out.print(command.name);
+      out.print(" ");
+    }
+  }
+  out.println();
+}
+
+const std::vector<Command> serialCommands = {
+  {"help", doHelp}
+};
+
+const std::vector<Command>&
+SerialInput::commands() const
+{
+    return serialCommands;
+}
+
+void
+SerialInput::doCommand() {
+  auto sched = MainLoop::instance()->scheduler;
+  Args args = Args(&m_buf);
+  const auto cmdName = args[0];
+
+  for(auto task : sched.tasks) {
+    for(auto &command : task->commands()) {
+      if (cmdName == command.name) {
+        command.func(args, m_logPrinter);
+        return;
+      }
+    }
+  }
+
+  m_logPrinter.println("Unknown command");
+  doHelp(args, m_logPrinter);
 }
 
 STATIC_ALLOC(SerialInput);
diff --git a/src/inputs/Serial.h b/src/inputs/Serial.h
index f6b7fee..6bbc286 100644
--- a/src/inputs/Serial.h
+++ b/src/inputs/Serial.h
@@ -3,14 +3,60 @@
 
 class SerialInput: public InputSource {
 public:
-    void onStart() override {
-        //Serial.begin();
+    SerialInput();
+    InputEvent read() override;
+
+    class LogPrinter : public Print {
+      private:
+        SerialInput* serial;
+        Ringbuf<char, 512> buf;
+      public:
+        LogPrinter(SerialInput* serial) : serial(serial) {};
+        size_t write(uint8_t byte) {
+          if (byte == '\n') {
+            char c;
+            Serial.print('\r');
+            while (buf.take(c)) {
+              Serial.write(c);
+            }
+            Serial.println();
+            serial->redrawPrompt();
+          } else {
+            buf.insert(byte);
+          }
+          return sizeof(byte);
+        }
+    };
+
+    void redrawPrompt();
+
+    Print* logPrinter() {
+        return &m_logPrinter;
     }
 
-    InputEvent read();
+    //static SerialInput::Command *s_root;
+    LogPrinter* printer() {
+      return &m_logPrinter;
+    }
+
+    const std::vector<Command> &commands() const override;
 
 private:
+    enum ParseState {
+      Normal,
+      EscapeSequence,
+      CSI
+    };
     String m_buf;
+    ParseState m_state;
+    char m_escapeSeq[3];
     void doCommand();
+    LogPrinter m_logPrinter;
+    bool m_canRedraw = true;
+    Ringbuf<String, 5> m_history;
+    int m_historyOffset = 0;
 
-}
+    InputEvent parseNormal(char nextChar);
+    InputEvent parseEscape(char nextChar);
+    InputEvent parseCSI(char nextChar);
+};