added date prompt

README.md

@@ -1,2 +1,2 @@
 in console, run:
-`deno task scrape`
+`deno task scraper`

deno.json

@@ -1,5 +1,5 @@
 {
   "tasks": {
-    "scrape": "deno run -A scraper.ts"
+    "scraper": "deno run -A scraper.ts"
   }
 }

scraper.ts

@@ -62,10 +62,103 @@ async function fetchSP500Tickers(): Promise<string[]> {
 // ------------------------------------------------------------
 // Yahoo Finance fetch
 // ------------------------------------------------------------
-const now = Math.floor(Date.now() / 1000);
-const thirtyDaysAgo = now - 30 * 24 * 60 * 60;
-const args = `?period1=${thirtyDaysAgo}&period2=${now}&interval=1d`;
-const closingEndpoint =(ticker:string)=>`https://query1.finance.yahoo.com/v8/finance/chart/${ticker}${args}`;
+function parseDate(dateStr: string): number {
+  const date = new Date(dateStr);
+  if (isNaN(date.getTime())) {
+    throw new Error(`Invalid date format: ${dateStr}. Use YYYY-MM-DD`);
+  }
+  return Math.floor(date.getTime() / 1000);
+}
+
+async function getDateRange(): Promise<{ period1: number; period2: number }> {
+  const args = Deno.args;
+  
+  // If command line args provided, use them
+  if (args.length === 1) {
+    const days = parseInt(args[0], 10);
+    if (isNaN(days) || days <= 0) {
+      throw new Error(`Invalid number of days: ${args[0]}`);
+    }
+    const now = Math.floor(Date.now() / 1000);
+    const daysAgo = now - days * 24 * 60 * 60;
+    console.log(`Using last ${days} days.`);
+    return { period1: daysAgo, period2: now };
+  }
+  
+  if (args.length >= 2) {
+    const startDate = parseDate(args[0]);
+    const endDate = parseDate(args[1]);
+    
+    if (startDate > endDate) {
+      throw new Error("Start date must be before end date");
+    }
+    
+    console.log(`Using date range from ${args[0]} to ${args[1]}.`);
+    return { period1: startDate, period2: endDate };
+  }
+  
+  // Interactive mode
+  console.log("\n=== Date Range Selection ===");
+  console.log("1. Last 30 days (default)");
+  console.log("2. Last N days (custom)");
+  console.log("3. Custom date range (YYYY-MM-DD)");
+  
+  const choice = prompt("Choose an option (1-3):", "1");
+  
+  if (choice === "1" || choice === null) {
+    // Default: last 30 days
+    const now = Math.floor(Date.now() / 1000);
+    const thirtyDaysAgo = now - 30 * 24 * 60 * 60;
+    console.log("Using last 30 days.");
+    return { period1: thirtyDaysAgo, period2: now };
+  }
+  
+  if (choice === "2") {
+    const daysStr = prompt("Enter number of days:", "30");
+    if (!daysStr) {
+      throw new Error("No days specified");
+    }
+    const days = parseInt(daysStr, 10);
+    if (isNaN(days) || days <= 0) {
+      throw new Error(`Invalid number of days: ${daysStr}`);
+    }
+    const now = Math.floor(Date.now() / 1000);
+    const daysAgo = now - days * 24 * 60 * 60;
+    console.log(`Using last ${days} days.`);
+    return { period1: daysAgo, period2: now };
+  }
+  
+  if (choice === "3") {
+    const dateRangeStr = prompt("Enter date range (YYYY-MM-DD YYYY-MM-DD):", "2025-12-18 2026-01-17");
+    if (!dateRangeStr) {
+      throw new Error("No date range specified");
+    }
+    
+    const dates = dateRangeStr.trim().split(/\s+/);
+    if (dates.length !== 2) {
+      throw new Error("Please provide two dates in format: YYYY-MM-DD YYYY-MM-DD");
+    }
+    
+    const startStr = dates[0];
+    const endStr = dates[1];
+    
+    const startDate = parseDate(startStr);
+    const endDate = parseDate(endStr);
+    
+    if (startDate > endDate) {
+      throw new Error("Start date must be before end date");
+    }
+    
+    console.log(`Using date range from ${startStr} to ${endStr}.`);
+    return { period1: startDate, period2: endDate };
+  }
+  
+  throw new Error("Invalid option selected");
+}
+
+let dateRange: { period1: number; period2: number };
+let args: string;
+let closingEndpoint: (ticker: string) => string;
 
 async function fetchLast30Closes(ticker: string): Promise<number[]> {
 
@@ -122,6 +215,7 @@ async function throttle<T>(
 
 function buildHtmlTable(
   results: { ticker: string; model: ReturnType<typeof linearRegression> }[],
+  dateRangeLabel: string,
 ): string {
   const rows = results.map(({ ticker, model }) => {
     const link = `<a href="https://www.tradingview.com/symbols/NASDAQ-${ticker}/?timeframe=6M" target="_blank">${ticker}</a>`;
@@ -153,6 +247,7 @@ function buildHtmlTable(
 </head>
 <body>
   <h1>S&P 500 Regression Results</h1>
+  <p><em>Date Range: ${dateRangeLabel}</em></p>
   <table>
     <thead>
       <tr>
@@ -160,7 +255,7 @@ function buildHtmlTable(
         <th class="extra">Slope</th>
         <th class="extra">Intercept</th>
         <th class="extra">R²</th>
-        <th>Growth (30d)</th>
+        <th>Growth</th>
       </tr>
     </thead>
     <tbody>
@@ -177,7 +272,31 @@ function buildHtmlTable(
 // ------------------------------------------------------------
 // Main Dump
 // ------------------------------------------------------------
+function getDateRangeLabel(): string {
+  const args = Deno.args;
+  
+  if (args.length === 0) {
+    return "Last 30 days";
+  }
+  
+  if (args.length === 1) {
+    const days = parseInt(args[0], 10);
+    return `Last ${days} days`;
+  }
+  
+  if (args.length >= 2) {
+    return `${args[0]} to ${args[1]}`;
+  }
+  
+  return "Unknown range";
+}
+
 async function Dump() {
+  // Initialize date range interactively
+  dateRange = await getDateRange();
+  args = `?period1=${dateRange.period1}&period2=${dateRange.period2}&interval=1d`;
+  closingEndpoint = (ticker: string) => `https://query1.finance.yahoo.com/v8/finance/chart/${ticker}${args}`;
+
   const spx = await ComputeTicker("^GSPC");
   if (!spx) {
     console.error("Could not get S&P Index data");
@@ -215,11 +334,11 @@ async function Dump() {
   results.sort((a, b) => b.model.growth - a.model.growth);
 
   // Build HTML
-  const html = buildHtmlTable(results);
+  const dateRangeLabel = getDateRangeLabel();
+  const html = buildHtmlTable(results, dateRangeLabel);
 
   await Deno.writeTextFile("sp500_regression.html", html);
   console.log("Dumped output to sp500_regression.html");
 }
 
 Dump();
-//console.log(closingEndpoint("^GSPC"))