From d01cf5790b6b114d61132cdcdce038788b12dc0a Mon Sep 17 00:00:00 2001
From: Lauchmelder <robert.trololo@gmail.com>
Date: Sat, 27 Nov 2021 20:54:04 +0100
Subject: [PATCH] started working on parser

---
 examples/test.gs          |  5 +--
 src/geometry.ts           | 29 +--------------
 src/parser/instruction.ts | 18 +++++++++
 src/parser/parameter.ts   | 35 ++++++++++++++++++
 src/parser/parser.ts      | 77 +++++++++++++++++++++++++++++++++++++++
 5 files changed, 134 insertions(+), 30 deletions(-)
 create mode 100644 src/parser/instruction.ts
 create mode 100644 src/parser/parameter.ts
 create mode 100644 src/parser/parser.ts

diff --git a/examples/test.gs b/examples/test.gs
index 7c0d49b..1b5f447 100644
--- a/examples/test.gs
+++ b/examples/test.gs
@@ -1,3 +1,2 @@
-point(3 | 4)
-
-point(6 | 7)
\ No newline at end of file
+point(3, 4) -> A
+line(A, point(7, 8))
\ No newline at end of file
diff --git a/src/geometry.ts b/src/geometry.ts
index 63f76b6..7443bb0 100644
--- a/src/geometry.ts
+++ b/src/geometry.ts
@@ -1,5 +1,6 @@
 /// <reference path="vector.ts" />
 /// <reference path="shapes.ts" />
+/// <reference path="parser/parser.ts" />
 
 function loadScript(filepath: string): string
 {
@@ -32,33 +33,7 @@ class Geometry extends HTMLElement
         let sourceFile = this.getAttribute("src");
         let content = loadScript(sourceFile);
 
-        let lines = content.split("\n");
-        for(let line of lines)
-        {
-            if(line === "\r")
-            {
-                console.log("empty");
-                continue;
-            }
-
-            let instruction = line.split("(")[0];
-
-            switch(instruction)
-            {
-                case instruction:
-                {
-                    let coords = line.split("(")[1].split("|");
-                    console.log(coords);
-                    break;
-                }
-
-                default:
-                {
-                    console.log("something else");
-                    break;
-                }
-            }
-        }
+        let parser = new Parser(content);
 
         this.attachShadow({mode: "open"});
         let canvas = document.createElement("canvas");
diff --git a/src/parser/instruction.ts b/src/parser/instruction.ts
new file mode 100644
index 0000000..1a381f6
--- /dev/null
+++ b/src/parser/instruction.ts
@@ -0,0 +1,18 @@
+enum InstructionType
+{
+    Point,
+    Line,
+    Circle
+}
+
+class Instruction 
+{
+    public fn: InstructionType;
+    public params :Parameter[];
+
+    constructor(type: InstructionType)
+    {
+        this.fn = type;
+        this.params = [];
+    }
+}
\ No newline at end of file
diff --git a/src/parser/parameter.ts b/src/parser/parameter.ts
new file mode 100644
index 0000000..ec2fd56
--- /dev/null
+++ b/src/parser/parameter.ts
@@ -0,0 +1,35 @@
+enum ParameterType 
+{
+    Instruction,
+    Identifier,
+    Number
+}
+
+abstract class Parameter 
+{
+    public type: ParameterType;
+
+    constructor(type: ParameterType)
+    {
+        this.type = type;
+    }
+
+    abstract eval();
+}
+
+class NumberParameter extends Parameter 
+{
+    public val: number;
+
+    constructor(val: number)
+    {
+        super(ParameterType.Number);
+
+        this.val = val;
+    }
+
+    eval()
+    {
+        return this.val;
+    }
+}
diff --git a/src/parser/parser.ts b/src/parser/parser.ts
new file mode 100644
index 0000000..9f10096
--- /dev/null
+++ b/src/parser/parser.ts
@@ -0,0 +1,77 @@
+/// <reference path="parameter.ts" />
+/// <reference path="instruction.ts" />
+
+class Parser
+{
+    private instructions: Instruction[];
+
+    constructor(source: string)
+    {
+        this.instructions = [];
+        let lines = source.split(/\r?\n/);
+        for(let line of lines)
+            this.parseInstruction(line);
+    }
+
+    private parseInstruction(instruction: string): boolean
+    {
+        // If the instruction is an empty line, do nothing for now
+        if(instruction === "")
+            return false;
+        
+        // match the pattern "text(text)"
+        let matches = instruction.match(/[A-Za-z]*\(.*\)/);
+        if(matches === null)    // no match found
+        {
+            console.error("Invalid syntax");
+            return false;
+        }
+
+        if(matches.length > 1)  // more than one match
+        {
+            console.error("Script may only contain one instruction per line");
+            return false;
+        }
+
+        let instr = matches[0]; // get the instruction
+        instr = instr.split(" ").join("");
+        let paranthesisPos = instr.search(/\(/);    // Find the position of the first opening paranthesis
+
+
+        let symbol = instr.substr(0, paranthesisPos);   // get function name
+        let paramlist = instr.substring(paranthesisPos + 1, instr.length - 1); // get parameter list
+        
+        let match;
+        let params = [];
+        while((match = paramlist.search(/,(?![^\(]*\))/)) !== -1)
+        {
+            params.push(paramlist.substring(0, match));
+            paramlist = paramlist.substring(match + 1, paramlist.length);
+        }
+        params.push(paramlist);
+
+        this.instructions.push(new Instruction(InstructionType.Point));
+        for(let param of params)
+        {
+            if(!this.parseParameter(param))
+            {
+                console.error("Error during parameter parsing");
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    private parseParameter(parameter: string): boolean
+    {
+        let match = parameter.search(/\d*\.?\d*$/);
+        if(match === 0)
+        {
+            this.instructions[this.instructions.length - 1].params.push(new NumberParameter(4));
+            return true;
+        }
+
+        return false;
+    }
+}