From 93042e103e2fbcb9154e5e65791fe1bf76f57b63 Mon Sep 17 00:00:00 2001
From: Eugene Zolenko <ezolenko@smarttech.com>
Date: Tue, 7 Feb 2017 18:46:44 -0700
Subject: [PATCH] - cache for transpiled code and diagnostics

---
 package.json     |  9 ++++-
 rollup.config.js |  4 +-
 src/cache.ts     | 99 ++++++++++++++++++++++++++++++++++++++++++++++++
 3 files changed, 109 insertions(+), 3 deletions(-)
 create mode 100644 src/cache.ts

diff --git a/package.json b/package.json
index d3113ca..d90553b 100644
--- a/package.json
+++ b/package.json
@@ -23,19 +23,24 @@
     "lint": "tslint -c ./tslint.json src/*.ts",
     "postinstall": "typings install"
   },
-  "dependencies": {},
+  "dependencies": {
+    "graphlib": "^2.1.1",
+    "object-hash": "^1.1.5",
+    "rollup-pluginutils": "^2.0.1",
+  },
   "peerDependencies": {
     "typescript": "^2.1.5"
   },
   "devDependencies": {
     "@alexlur/rollup-plugin-typescript": "^0.8.1",
+    "@types/graphlib": "^2.1.3",
     "@types/node": "^6.0.53",
+    "@types/object-hash": "^0.5.28",
     "glob": "^7.1.1",
     "glob-fs": "^0.1.6",
     "lodash": "^4.17.4",
     "rimraf": "^2.5.4",
     "rollup": "^0.41.4",
-    "rollup-pluginutils": "^2.0.1",
     "tslib": "^1.5.0",
     "tslint": "^4.1.1",
     "typescript": "^2.1.5",
diff --git a/rollup.config.js b/rollup.config.js
index ff8c2c4..0264deb 100644
--- a/rollup.config.js
+++ b/rollup.config.js
@@ -10,7 +10,9 @@ export default {
 		'fs',
 		'object-assign',
 		'rollup-pluginutils',
-		'typescript'
+		'typescript',
+		'graphlib',
+		'object-hash'
 	],
 
 	plugins: [
diff --git a/src/cache.ts b/src/cache.ts
new file mode 100644
index 0000000..e13c792
--- /dev/null
+++ b/src/cache.ts
@@ -0,0 +1,99 @@
+import * as ts from "typescript";
+import * as graph from "graphlib";
+import * as hash from "object-hash";
+import * as fs from "fs";
+
+interface ICode
+{
+	code: string;
+	map: string;
+}
+
+interface INodeLabel
+{
+	dirty?: boolean;
+	hash?: string;
+}
+
+export class Cache
+{
+	private dependencyTree: graph.Graph;
+	private treeComplete: boolean = false;
+
+	constructor(private cacheRoot: string, private options: ts.CompilerOptions, rootFilenames: string[])
+	{
+		this.cacheRoot = `${this.cacheRoot}/${hash.sha1({ rootFilenames, options: this.options })}`;
+		fs.mkdirSync(this.cacheRoot);
+
+		let dependencyTreeFile = `${this.cacheRoot}/tree`;
+		if (fs.existsSync(dependencyTreeFile))
+		{
+			let data = fs.readFileSync(`${this.cacheRoot}/tree`, "utf8");
+
+			this.dependencyTree = graph.json.read(JSON.parse(data));
+		}
+		else
+			this.dependencyTree = new graph.Graph();
+	}
+
+	public setDependency(importee: string, importer: string): void
+	{
+		this.dependencyTree.setEdge(importer, importee);
+	}
+
+	public lastDependencySet()
+	{
+		this.treeComplete = true;
+	}
+
+	public markAsDirty(fileName: string, snapshot: ts.IScriptSnapshot)
+	{
+		this.dependencyTree.setNode(fileName, { dirty: true });
+	}
+
+	public isDirty(fileName: string, snapshot: ts.IScriptSnapshot): boolean
+	{
+		let label = this.dependencyTree.node(fileName) as INodeLabel;
+
+		// TODO: also if any dependencies are dirty
+
+		return label.dirty;
+	}
+
+	public getCompiled(fileName: string, snapshot: ts.IScriptSnapshot, transform: () =>  ICode | undefined): ICode | undefined
+	{
+		let path = this.makePath(fileName, snapshot);
+
+		if (!fs.existsSync(path) || this.isDirty(fileName, snapshot))
+		{
+			let data = transform();
+			this.setCompiled(path, fileName, snapshot, data);
+			return data;
+		}
+
+		return JSON.parse(fs.readFileSync(path, "utf8")) as ICode;
+	}
+
+	public getDiagnostics(fileName: string, snapshot: ts.IScriptSnapshot, check: () => ts.Diagnostic[]): ts.Diagnostic[]
+	{
+
+	}
+
+	private setDiagnostics(path: string, fileName: string, snapshot: ts.IScriptSnapshot, data: ts.Diagnostic[]): void
+	{
+
+	}
+
+	private setCompiled(path: string, fileName: string, snapshot: ts.IScriptSnapshot, data: ICode)
+	{
+		fs.writeFileSync(path, JSON.stringify(data));
+
+		this.markAsDirty(fileName, snapshot);
+	}
+
+	private makePath(fileName: string, snapshot: ts.IScriptSnapshot): string
+	{
+		let data = snapshot.getText(0, snapshot.getLength());
+		return `${this.cacheRoot}/${hash.sha1({ data, fileName })}`;
+	}
+}