initial parser logic. still needs fixing for Text

src/api/index.ts

@@ -8,6 +8,7 @@ export const api = new Elysia({ prefix: '/api' })
     const releaseYear = movie.release_date.substring(0, 4);
     const voteAverage =  movie.vote_average.toFixed(2);
 
+    // return Gin.render("card", movie);
     return Yuck.renderMoviePage(
       movie.id,
       movie.title, 
@@ -22,6 +23,7 @@ export const api = new Elysia({ prefix: '/api' })
     const releaseYear = movie.release_date.substring(0, 4);
     const voteAverage =  movie.vote_average.toFixed(2);
 
+    // return Gin.render("movie", movie);
     return Yuck.renderMoviePage(
       movie.id,
       movie.title, 
@@ -33,5 +35,6 @@ export const api = new Elysia({ prefix: '/api' })
   })
   .get("providers/watch/:id", async ({ params: { id } }) => {
     const providers = await API.providers(parseInt(id));
+    // return Gin.render("providers", movie);
     return Yuck.renderProviderPage()
   });

src/util/gin.ts

@@ -1,39 +1,253 @@
-// TODO: Finish template engine and parse the data like god intended
+
-type GinNode = {
+const example =
+`Dear {{.Name}},
+{{if .Attended}}
+It was a pleasure to see you at the wedding.
+{{- else}}
+It is a shame you couldn't make it to the wedding.
+{{- end}}
+{{with .Gift -}}
+Thank you for the lovely {{.}}.
+{{end}}
+Best wishes,
+Josie`;
+
+type Node = {
+    type: 'Text' | 'Data' | 'Conditional' | 'Marker' | 'Container' | 'Empty'
     
-    path: string;
+    // Text
-    children: GinNode[];
+    startIndex?: number;
+    endIndex?: number;
+    text?: string;
+
+    // Data
+    key?: string;
+
+    // Conditional
+    conditionType?: 'if' | 'with';
+    condition?: Node;
+    consequent?: Node;
+    alternative?: Node;
+
+    // Marker
+    markerType?: 'else' | 'end';
+
+    // Container
+    placeholders?: Node[],
+
+    // Scoping
+    parent?: Node;
+};
+
+function parse(text: string): Node {
+     let root: Node = {
+        type: 'Container',
+        placeholders: []
+    };
+    return _parse(text, root);
 }
 
-class Gin {
+function _parse(text: string, root: Node): Node {
+     if (!text || text.length < 1) {
+        return root;
+    };
 
-    /**
+    let i = 0;
-     * Preprocess template files from a given path into some data structure that tags them and notes substitutable areas
+    const open = [];
-     * 
+    let prevScope = root;
-     * @param path
+    let scope = root;
-     */
-    setup(path: string) {}
 
-    /**
+    let textNode: Node = {
-     * Creates HTML string from named template and supplied data
+        type: 'Text',
-     * 
+        startIndex: 0,
-     * @param name 
+        endIndex: 0
-     * @param mappings 
-     */
-    render(name: string, data: Record<string, string | number>): string {
-        return '';
     }
 
-    /**
+
-     * Constructs actual dependency tree. Parsing is prob gonna be some recursive business
+    let altPath = false;
-     * 
+    while (i < text.length) {
-     * @param path 
+        textNode.endIndex = i;
-     */
+
-    private crawl(path: string): GinNode | undefined {
+        if (text.substring(i, i+2) == '{{') {
-        return;
+            open.push(i);
+        }
+
+        if (text.substring(i, i+2) == '}}') {
+            textNode.parent = scope;
+            textNode.text = text.substring(textNode.startIndex!, textNode.endIndex!)
+            switch (scope.type) {
+                case 'Container':
+                    scope.placeholders!.push(textNode)
+                    break;
+                case 'Conditional':
+                    const placeholders = (altPath) ? scope.alternative!.placeholders! : scope.consequent!.placeholders!;
+                    placeholders.push(textNode);
+            }
+
+            const j = open.pop()!;
+
+            textNode = {
+                type: 'Text',
+                startIndex: j+2,
+                endIndex: i
+            };
+
+            const command = parseCommand(text, j+2, i);
+            command.parent = scope;
+
+            if (command.type == 'Marker') {
+                switch (command.markerType) {
+                    case 'end':
+                        scope = prevScope;
+                        altPath = false;
+                        break;
+                    case 'else':
+                        altPath = true;
+                        break;
+                }
+            }
+            else if (command.type == 'Conditional') {
+                scope.placeholders!.push(command)
+                prevScope = scope;
+                scope = command!;
+            } else {
+                switch (scope.type) {
+                    case 'Container':
+                        scope.placeholders!.push(command)
+                        break;
+                    case 'Conditional':
+                        const placeholders = (altPath) ? scope.alternative!.placeholders! : scope.consequent!.placeholders!;
+                        placeholders.push(command);
+                        break;
+                }
+            }
+        }
+        i++;
+    }
+
+    if (textNode.startIndex! < textNode.endIndex!) {
+        textNode.parent = scope;
+        textNode.text = text.substring(textNode.startIndex!, textNode.endIndex!)
+        scope.placeholders!.push(textNode);
+    }
+
+    return root;
+}
+
+function parseCommand(text: string, i: number, j: number): Node {
+    let node: Node = {
+        type: 'Empty'
+    };
+
+    if (i >= j) {
+        return node;
+    };
+
+    let view = text.substring(i, j);
+
+
+    // not supported
+    if (view.startsWith("- ")) {
+        i += 2;
+        view = text.substring(i, j);
+    }
+    
+    // not supported
+    if (view.endsWith(" -")) {
+        j -= 2;
+        view = text.substring(i, j);
+    }
+    
+    if (view.startsWith('.')) {
+        node = parseDataText(view);
+    }
+    
+    if (view.startsWith('if') || view.trim().startsWith('with')) {
+        node = parseConditionalText(text, i, j);
+    }
+
+    if (view == 'else' || view == 'end') {
+        node.type = 'Marker';
+        node.markerType = view;
+    }
+    return node;
+};
+
+function parseConditionalText(text: string, i: number, j: number): Node {    
+    const view = text.substring(i, j);
+
+    let node: Node = {
+        type: 'Conditional',
+        conditionType: view.startsWith('if') ? 'if' : 'with',
+        consequent: {
+            type: 'Container',
+            placeholders: []
+        },
+        alternative: {
+            type: 'Container',
+            placeholders: []
+        },
+    };
+    node.consequent!.parent = node;
+    node.alternative!.parent = node;
+
+    const pipelineStart = i + view.indexOf(' ') + 1;
+    const pipelineView = text.substring(pipelineStart, j)
+
+    if (pipelineView.startsWith('.')) {
+        node.condition = {
+            type: 'Data',
+            key: pipelineView,
+            parent: node,
+        }
+    } else {
+        node.condition = {
+            type: 'Text',
+            startIndex: pipelineStart,
+            endIndex: j,
+            text: pipelineView,
+            parent: node,
+        }
+    }
+
+    return node;
+}
+
+function parseDataText(text: string): Node {
+    return {
+        type: 'Data',
+        key: text.trim()
+    };
+}
+
+function printNode(node: Node, offset='') {
+    switch (node.type) {
+        case 'Conditional':
+            console.log(`${offset}${node.conditionType}`);
+            console.log(`${offset}Condition:\n`)
+            printNode(node.condition!, offset + '\t')
+            console.log(`${offset}Then:\n`)
+            printNode(node.consequent!, offset + '\t')
+            console.log(offset + 'Else:\n')
+            printNode(node.alternative!, offset + '\t')
+            break;
+        case 'Container':
+            console.log(offset + node.type)
+            for (let p of node.placeholders ?? []) {
+                printNode(p, offset + '|__');
+            }
+            break;
+        case 'Data':
+            console.log(`${offset}${node.type} [key=${node.key}]`);
+            break;
+        case 'Text':
+            console.log(`${offset}${node.type} [text=${JSON.stringify(node.text)}]`);
+        default:
+            console.log(`${offset}${node.type}`);
     }
 }
 
+printNode(parse(example));
 /**
  * Stopgap :(
  */