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 # csg
 
 csg is the "complicated (static) site generator".
-It's a decently simple static site generator, written in bash, with the capability to be extended via awk scripts.
+It's a somewhat simple static site generator, written in bash, with many "poweruser" features thanks to [awk](TODO).
 
-The overall design is heavily inspired by [Roman Zolotarev](TODO)'s [ssg](TODO), however the codebase is made from the ground up with the goal of adding more features.
-Mainly:
+The overall design is heavily inspired by [Roman Zolotarev](https://romanzolotarev.com/)'s [ssg](https://romanzolotarev.com/ssg.html), however the codebase is completely different, with the added bonus of:
 
-- csg supports arbitrary file modifications via awk, which will have access to:
-  - git-based "last edited" and "first created" timestamps, which are also cached for fast retrievals
-  - word count
+- arbitrary file modifications via awk
+- git-based "created" and "edited" timestamps
 - support for (multiple) description and title meta tags
 - support for custom title format
 
-## How it works
+## How to use
 
-You write your pages in Markdown, you'll also need to have a `_header.html` and `_footer.html` files in the source of your site.
-Every page gets converted to HTML, your awk scripts are ran and then `_header.html` is slapped on the top, `_footer.html` on the bottom.
-All other files are copied to the output repository as-is.
+Your content is inside a "source" folder, while the resulting website files will be put in a "destination" folder.
+Webpages are written in Markdown, which is then transformed into HTML with the proper edits, and finally `_header.html` and `_footer.html` are stitched on top and bottom.
+Everything else is taken as-is.
 
-## How to use
+Additional features are available with [awk](TODO).
+By default, the title, description and word count are taken from every Markdown file.
+The title and description will be put in place of `[TITLE]` and `[DESCRIPTION]` inside `_header.html`.
+You can also create/use your own awk scripts for further page modification (all three values will also be available inside those scripts).
+
+*Note:* if you don't want the additional features, just use [ssg](https://romanzolotarev.com/ssh.html)
+
+### Writing your own scripts
+
+There are some things you must consider while creating an awk script:
+
+1. It will be ran on the generated HTML pages
+2. It's name **must** start with a capital letter
+   - You can also create so-called "libraries", mainly awk scripts with only function definitions
+   - libraries **must** start with a `#` character in their name, and are included with every script
+3. The current line **mustn't** be printed (unless you want to add a line to the file)
+   - With awk we can modify only certain lines, but the easiest way to get the whole file with the modified lines, is to just print every line.
+     Such a rule is "appended" to the end of your script.
+   - Do modifications to `$0` instead of `print (fancy expression)`
+   - If you don't want to print a line, do `$0 = 0`
+4. Every script **must** begin with a `# regex` line
+   - For optimisation purposes, a script is ran only on the files which match the given regular expression
+   - The regex is on the whole path, so you could make changes (for example) to specific pages or all pages inside folders
+   - The regular expression is fed to `find -regex`, so for exact support view `find`'s documentation
+5. Script variables **mustn't** collide and you **mustn't** use `exit` or `nextfile`
+   - Also for optimisation purposes, scripts with the same regex are combined into one
+6. Inside your scripts you'll have the `title`, `description`, `words`, `created` and `edited` variables available
+   The last two will be dates in the format "%d %B %Y", and are only available if your website uses git.
+
+### Generate website with the script
+
+csg comes with a help message, which contains everything you might want to know for running the script:
+
+```
+Usage: csg [-h | -? | --help]
+       csg <source_dir> <destination_dir> <title_format> [<scripts_dir>]
 
-This repository comes with a small demo setup, so just run:
+Options:
+  -h, -?, --help    Print this help message (also available when given no
+                    arguments)
+
+Arguments:
+  <source_dir>         Folder which contains source files
+  <destination_dir>    Folder in which the generated site will be put
+  <title_format>       Format string for page title
+                       Accepts any text or HTML, & is replaced with contents
+                       title (first h1 header).
+  <scripts_dir>        Optional, folder which contains awk script for editing of
+                       generated webpages.
+
+Variables (you can predefine):
+  CSG_TIMESTAMP_FILE    File path for git-based timestamps (when git exists)
+                        Default: "./timestamps.txt"
+                        Disable: ""
+  CSG_TMP_DIR           Directory to put temporary files
+                        Default: "/tmp"
+  CSG_AWK               awk executable and flags
+                        Default: searches for gawk
+  CSG_MD_TO_HTML        Program to convert Markdown to HTML and it'\''s flags
+                        Default: searches for lowdown
+
+Dependencies (required):
+  bash, printf, find, cpio
+
+
+csg - complicated (static) site generator
+Created by Syndamia, https://gitlab.com/Syndamia/csg
+```
+
+### Demo
+
+This repository comes with a small demo setup.
+To test it out, run:
 
 ```bash
-csg "./demo/awk-edits" "./demo/src" "./demo/website" "& - Demo"
+./csg ./demo/src ./demo/website '& - Demo' ./demo/awk-edits
 ```
 
-The first argument is the folder in which you'll have your awk file modification scripts.
-The second is the folder with your website source.
-The third is the output folder.
-The fourth is the title format, where & is a special symbol, which will be replaced with the title of the page (the first h1 header).
+You will find your website, ready to be served, inside `./demo/website`.
+
+## Future features
+
+1. I would love to make it POSIX compatible, however this will require a good amount of work and will introduce inefficiencies, so for now it's left for the future
+2. Right now the whole website is regenerated every time, it's important to add a system for updating only the currently changed pages.
+   I'm not entirely sure how to do that, since we remove the source Markdown after it is converted to HTML, current thinking leads me to a file containing lines of "filepath hash", but we'll see.