Add write-up

Author: jasonhtpham

README.md

@@ -1,64 +1,11 @@
-# svelte app
+This Dapp is written as part of my intern with Flex Dapps Pty Ltd.
 
-This is a project template for [Svelte](https://svelte.dev) apps. It lives at https://github.com/sveltejs/template-webpack.
+The front-end is written in <a href="https://svelte.dev/"> Svelte </a>
 
-To create a new project based on this template using [degit](https://github.com/Rich-Harris/degit):
+The app uses `IPFS` as a decentralized file storage and `webpack` to facilitate the web functionalities.
 
-```bash
-npx degit sveltejs/template-webpack svelte-app
-cd svelte-app
-```
+<a href="https://github.com/ipfs/js-ipfs"> JS-IPFS </a> is used to interact with IPFS.
 
-*Note that you will need to have [Node.js](https://nodejs.org) installed.*
+And, of course, this cannot be a Dapp without using `web3`, find out more <a href="https://web3js.readthedocs.io/en/v1.2.0/index.html"> here </a>.
 
-
-## Get started
-
-Install the dependencies...
-
-```bash
-cd svelte-app
-npm install
-```
-
-...then start webpack:
-
-```bash
-npm run dev
-```
-
-Navigate to [localhost:8080](http://localhost:8080). You should see your app running. Edit a component file in `src`, save it, and the page should reload with your changes.
-
-
-## Deploying to the web
-
-### With [now](https://zeit.co/now)
-
-Install `now` if you haven't already:
-
-```bash
-npm install -g now
-```
-
-Then, from within your project folder:
-
-```bash
-now
-```
-
-As an alternative, use the [Now desktop client](https://zeit.co/download) and simply drag the unzipped project folder to the taskbar icon.
-
-### With [surge](https://surge.sh/)
-
-Install `surge` if you haven't already:
-
-```bash
-npm install -g surge
-```
-
-Then, from within your project folder:
-
-```bash
-npm run build
-surge public
-```
+Run this app by installing aforementioned dependencies and `npm run dev`

contracts/ethergram.sol

@@ -0,0 +1,64 @@
+pragma solidity >=0.4.0;
+
+import "./etherpostinterface.sol";
+
+contract EtherGram is EtherPostInterface {
+    
+    mapping (address => bytes32[]) posts;
+    
+    mapping (bytes32 => address) posterOf;
+    
+    mapping (bytes32 => uint) clapCount;
+    
+    mapping (bytes32 => bytes32[]) comments;
+    
+    bytes32[] allPosts;
+    
+    //Chech if the post exists
+    modifier postExist(bytes32 _ipfsHash) {
+        require(posterOf[_ipfsHash] != address(0));
+        _;
+    }
+    
+    //Check if the post is new (not exists)
+    modifier newPost(bytes32 _ipfsHash) {
+        require(posterOf[_ipfsHash] == address(0));
+        _;
+    }
+    
+    function upload(bytes32 _ipfsHash) public newPost(_ipfsHash) {
+        
+        posts[msg.sender].push(_ipfsHash);
+        posterOf[_ipfsHash] = msg.sender;
+        allPosts.push(_ipfsHash);
+        
+        emit LogUpload(msg.sender, _ipfsHash);
+    }
+    
+    function getAllPosts() public view returns(bytes32[] memory){
+        return allPosts;
+    }
+    
+    function getPostsByUploader(address _uploader) public view returns(bytes32[] memory){
+        return posts[_uploader];
+    }
+    
+    function clap(bytes32 _ipfsHash) public postExist(_ipfsHash) {
+        clapCount[_ipfsHash]++;
+        emit LogClap(msg.sender, _ipfsHash);
+    }
+    
+    function getClapCount(bytes32 _imageHash) public postExist(_imageHash) returns(uint) {
+        return clapCount[_imageHash];
+    }
+    
+    function comment(bytes32 _imageHash, bytes32 _commentHash) public postExist(_imageHash) {
+        comments[_imageHash].push(_commentHash);
+        emit LogComment(msg.sender, _imageHash, _commentHash, now);
+    }
+    
+    function getComments(bytes32 _imageHash) public postExist(_imageHash) returns(bytes32[] memory) {
+        return comments[_imageHash];
+    }
+      
+}

contracts/etherpostinterface.sol

@@ -0,0 +1,21 @@
+pragma solidity 0.4.24;
+
+/**
+ * @title EtherPostInterface
+ * @author RMIT Online (Flex Dapps)
+ * @dev EtherPostInterface for storing image uploads, comments and claps.
+ * IPFS hashes are encoded to bytes32 with Qm removed.
+ */
+contract EtherPostInterface {
+
+  event LogUpload(address uploader, bytes32 ipfsHash);
+  event LogClap(address clapper, bytes32 ipfsHash);
+  event LogComment(address commenter, bytes32 imageHash, bytes32 commentHash, uint timestamp);
+
+  function upload(bytes32 ipfsHash) public;
+//   function getUploads(address uploader) public returns(bytes32[] memory);
+  function clap(bytes32 ipfsHash) public;
+  function getClapCount(bytes32 ipfsHash) public returns(uint);
+  function comment(bytes32 imageHash, bytes32 commentHash) public;
+  function getComments(bytes32 ipfsHash) public returns(bytes32[] memory);
+}