Developing the simplest messaging system for extreme conditions with a web interface using a single AI prompt.
AI Request for Generating PHP, HTTP, and JavaScript Messenger Code

Write code using PHP, HTTP, and JavaScript to send messages to a web page.
The following steps are required:

1. A web page, send.php, with a text input field for sending to a PHP script: http://mysite.com/page.php
The text input limit is 120 characters.
Send button: "Send Message"
When the button is clicked, the entered data is sent, the number of characters sent is counted, and this number is written as characters to the file, count.txt, in the same folder.
The data in the file, count.txt, is completely overwritten each time the button is clicked.
If the file, count.txt, does not exist in the folder, it is created with read and write access.

2. The page.php PHP script that receives the data:
- writes it to the messages.txt file in the same folder. If the messages.txt file does not exist, it must be created, and the file must be readable and writable (attributes) must be enabled. If the write is successful, the message "Data saved" is written to the screen (web page). If the data is not written, "Data Not Saved" is written to the web page.
The data in the messages.txt file is completely overwritten each time.
- reads text data from the received.txt file into the $cnt variable.
If the received.txt file does not exist, it is created with read-write permissions, the text value 0 is written to it, and the $cnt variable is assigned the value 0.

If the received.txt file exists, its value is read into the $cnt variable.

When writing to the messages.txt file, the number of characters written is counted and this value is added to the $cnt variable. The new value of the $cnt variable is written to the received.txt file.

3. All .txt files used contain text data. All file I/O operations must begin with opening the file and end with closing the file.
4. Error handling must be written.

5. Write the HTML, PHP, and JavaScript code for the view.php web page in the style of the send.php web page (from step 1) to read the contents of the messages.txt file and display them on the screen in a data entry field, where they can be edited or copied.


Technical Specifications: Development of a Messaging System with a Web Interface

1. Project: A web system for sending, receiving, and managing text messages.
2. Objective: Create a three-page web application (PHP, JavaScript, HTML) with functionality for sending, server-side processing, and viewing text data through file system interaction.
3. Functional Requirements:
3.1. Send Page (send.php):
Interface Elements:
Text field (textarea) for entering a message.
Hard limit on the length of input text on the client side: 120 characters.
Real-time character counter (format: X/120).
Send button with the text "Send Message."
Client-side Logic (JavaScript):
Message length validation before sending.
Asynchronous data sending (POST request) to a remote script at http://mysite.com/page.php.
After sending, clear the input field and reset the counter.
Server-side logic (PHP in save_count.php):
Get the number of characters in the sent message.
Create (if it doesn't exist) or completely overwrite the file count.txt in the current directory.
Write a string representation of the number of characters sent to count.txt.
Set access rights for the created file: read and write (0666).
Return the operation status (JSON).

3.2. Server-side processing script (page.php):
Input data: Text message received via the POST method.
Output data: Text response "Data saved" (success) or "Data Not Saved" (error).
Main workflow:
Writing a message:
The received message is completely overwritten in the messages.txt file.
If the file doesn't exist, it is created with permissions 0666.
The number of characters written is counted.
Working with the aggregate counter:
Read the current value from the received.txt file into the $cnt variable.
If the file does not exist, create it with permissions 0666, write the value 0, and assign $cnt = 0.
Updating the counter:
The number of characters written in step 1 is added to the $cnt value.
The new $cnt value is completely overwritten in the received.txt file.
Error handling: If any input/output error occurs, the script should return the "Data Not Saved" status.

3.3. View and control page (view.php):
Style: Should match the design of the send.php page.
Interface elements:
Area (e.g., textarea) for displaying the contents of the messages.txt file.
File information panel (path, size, modification time, access rights).
View/Edit mode switch.
A set of control buttons: "Refresh," "Save," "Copy to Clipboard," "Clear," and "Download."
Character count indicator.

System message display area.

Navigation links to other system pages.

Functionality:

Data loading: Asynchronously reads and displays the current contents of messages.txt when the page loads.

Editing: In editing mode, the user can change the text in the input field. The "Save" button becomes active only when changes have been made.

Saving: Asynchronously sends the changed content to the server to completely overwrite the messages.txt file, updating the associated counter in received.txt.

Auxiliary functions: Copy content to the clipboard, download a file, clear the input field.

Validation: Visual warning when the 120-character limit is exceeded.

4. General Technical Requirements:

Security and Reliability:

All file read/write operations must explicitly open and close file descriptors.

Mandatory handling and logging of potential errors (missing files, access rights issues, I/O failures).

Input data validation on both the client and server sides.

Architecture:

Use asynchronous requests (Fetch API) for interaction between the client and server without page reloads.

Clear separation of concerns: HTML/PHP for markup and primary logic, JavaScript for interactivity.

File Handling:

All .txt files (count.txt, messages.txt, received.txt) contain only text data.

The access rights to created files must be explicitly set to read and write (0666).

5. Additional components (implemented):

get_messages.php — auxiliary API endpoint for securely reading the contents of messages.txt.

update_messages.php — auxiliary API endpoint for securely writing to messages.txt and updating received.txt.

index.php — the system's central index page with navigation and file status.





(c) by Valery Shmelev  https://oflameron.com

https://t.me/s/llmsource/