Part-2b.-Organise-my-first-service.md

@@ -64,6 +64,37 @@ But no one wants to inline HTML into code, and since we just installed a templat
 
 Now refactoring code using an unfamiliar editor is a daunting task, so depending on how long it takes, we might have to skip ahead after this. Keep calm and don't panic, it'll be fine.
 
+New vim commands which might be useful.
+
+In NORMAL-mode (not insert).
+
+* `gg` goes to top of file
+* `GG` goes to bottom
+* `/`  searches a file, using regex. (<Enter> to search, `n` to next, `:noh` to clear search results)
+* `yy` on a line, copies it
+* `dd` on a line, cuts it
+* `p`  pastes below current line
+
+A lot of vim commands can be composed, so typing `10G` will move the cursor to line 10 in the file.
+`d5d` will cut from current line, and 5 down, there are more, a lot more.
+But this isn't actually workshop on vim, but remember this...
+
+The designers of vim believe that people _edit_ files more than they _create_ them,
+so vim is optimised towards modifying existing files, as appose to creating them.
+
+Pressing `v` puts vim into VISUAL-mode, as appose to `i` for INSERT-mode.
+In _visual-mode_ you can use the cursors to select in the buffer.
+
+As an example, if we are on line 10, press `v` and pres the down key a couple of times,
+and then press `d` - We'll cut those lines.
+
+And that brings us to the most import key, the one to rule them all.
+
+`u` will undo ;)
+
+Last one before we start, in _visual-mode_ select a few lines, and press `>`
+you just indented right.
+
 Lets take a look at the final result for _main.py_
 
 ```python
@@ -114,9 +145,58 @@ We've introduced to new features, namely support for _templates_ and _static fil
 The index function has gotten a new annotation, that "links" it to a template file.
 And we've removed the items route.
 
-As always, press `Esc` to ext insert-mode, and :w to save.
+As always, press `Esc` to exit insert-mode, and :w to save.
+
+Now come the hard part, the need to work with multiple files.
+The easy way, is to simply exit vim, and start vim on a new file, that could be `:q` and `vim api_router.py` 
+
+But for the brave, working with multiple files or buffers as vim calls them is a powerful skill.
+
+Here are the most useful commands...
+
+- To open a file (buffer) type `:e {filepath}` you can use tab-completion.
+- To list open buffers type `:ls`, note the number (n) to the left of each.
+- To switch buffers type `:b<n>`
+- To go to next buffer type `:bn`, and `:bp` for previous
+- To delete a buffer (~close it), type `:bd`
+  (this does not delete the file)
+
+It is also possible to go to an open buffer, by knowing its name, or part of it.
+Typing `:b <filename>` jumps to the buffer with that file, and of course, tab-completion is your friend.
+
+And finally, typing `:e .` will allow you to navigate the file system to open a file! ( _Now he tells me!_ )
+
+So, lets try...
+
+Navigate to the bottom of main.py, down to where the `@router.get("/items/{item_id}")` line is.
+Press `v` and arrow down to until the whole code block is selected.
+Press `d` to cut it, and `:w` to save the change.
+
+Type `:e api+<tab>` or `:e .` and navigate to open the api_router.py file we created earlier.
+Since this file is empty, simply press `p`to paste the cut-content from before.
+
+Press `gg` or arrow back up to the top of the file, and type in the remaining bits.
+
+Press `i` to enter _insert-mode_, and change the `@app` part to `@router`
+
+When the file looks like this, the free coffee is on me.
+
+```python
+from fastapi import APIRouter
+from typing import Optional
+
+router = APIRouter()
+
+@router.get("/items/{item_id}")
+def read_item(item_id: int, q: Optional[str] = None):
+    return {"item_id": item_id, "q": q}
+
+```
+
+`Esc`to return to _normal-mode_ and type `:w`to save, and delete that buffer `:bd`
+
+You are back in main.py, well done!! - I'll take it from here!
+
+Proceed to Part 3.
 
-Now come the hard part, the need to changes files.
-The easy way, is to simply exit vim, and start it on a new file, that is `:q` and `vim api_router.py` 
 
-But for the brave, working with multiple files, or buffers as vim calls them, is bordering on the advanced.
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