PriceCalc — Greek e-Shop Price Comparison & Markup Calculator

A desktop application that searches prices from Greek e-shops and calculates a recommended selling price based on configurable markup rules, reducing the time spent searching for and comparing retail prices, in an e-shop or physical store, by 98%

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Requirements

• Node.js v18 or later → https://nodejs.org
• Windows 10/11 x64 (or macOS 12+)
• Active internet connection (required for scraping)

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Installation & Setup

Option A — Run setup.bat (Windows)

1. Extract the ZIP file
2. Open the electron-pricer folder
3. Open a Command Prompt inside that folder (Shift + Right-click → "Open command window here")
4. Run:

setup.bat

Option B — Manual setup

# 1. Install dependencies
npm install

# 2. Install Playwright Chromium browser (~150MB)
npx playwright install chromium

# 3. Start in development mode
npm run dev

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Build Windows Installer (.exe)

npm run build:win

The installer will be created in the dist-electron/ folder.

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How It Works

Search Pipeline

1. Cache check (TTL: 60 minutes)
   → If we have recent results for this query, return them immediately

2. Skroutz (runs in parallel with Tier A shops)
   → 1 price only: the lowest price shown on the product page

3. Tier A shops (Plaisio, Public, Kotsovolos, e-shop, Germanos...)
   → 2 shops if Skroutz found the product
   → 3 shops if Skroutz did not find the product

4. Fallback: Tier B → Tier C shops if Tier A shops fail

5. Total: always 3 prices for the average (fewer = warning shown)

Recommended Price Logic (Priority Order)

1. Just above Skroutz (+2%) — if result is above minimum markup
2. Close to market average — if it improves on option 1
3. Markup minimum — fallback, always profitable

Final rounding: to .90 (e.g. €91.90)

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Markup Scale (default, fully editable in Settings tab)

Purchase cost (excl. VAT)	Markup
up to €3	100%
€3 – €7	70%
€7 – €15	45%
€15 – €30	30%
€30 – €60	22%
€60 – €120	16%
€120 – €200	12%
€200 and above	10%

VAT rate applied: 24%

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Project Structure

src/
├── main/                        # Electron Main Process (Node.js)
│   ├── index.js                 # App entry point
│   ├── ipc-handlers.js          # IPC bridge (main <-> renderer)
│   ├── db/
│   │   ├── database.js          # SQLite via sql.js (no compilation needed)
│   │   └── schema.sql           # Tables & default markup data
│   ├── scraper/
│   │   ├── engine.js            # Search orchestrator
│   │   ├── stealth.js           # Playwright stealth browser setup
│   │   ├── skroutz.js           # Skroutz scraper (primary source)
│   │   ├── priceUtils.js        # Shared price parsing & validation
│   │   └── shops/
│   │       ├── registry.js      # 50+ shops with CSS selectors & tiers
│   │       └── shopScraper.js   # Generic scraper for any registered shop
│   └── pricing/
│       └── calculator.js        # Markup & recommended price logic
└── renderer/                    # React UI (Vite + Tailwind)
    ├── App.jsx                  # Main layout & tab navigation
    ├── store/useStore.js        # Zustand global state
    └── components/
        ├── SearchBar.jsx        # Query + purchase price input
        ├── PriceTable.jsx       # Scraped prices table
        ├── MarkupPanel.jsx      # Active markup tier display
        ├── RecommendedPrice.jsx # Hero price + profit breakdown
        ├── Warnings.jsx         # Shipping & scraping warnings
        └── MarkupSettings.jsx   # Editable markup rules

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Anti-Scraping Measures

• Playwright Stealth plugin — hides all browser automation flags
• User-Agent rotation — pool of 5 realistic Chrome/Firefox UAs
• Human-like delays — 600–1800ms random delay between requests
• Block images/fonts/media — faster page load, less detectable
• Greek locale — el-GR language, Athens timezone & geolocation
• 60-minute cache — avoids repeat requests for the same product
• Max 1 request per site per search — respectful scraping

Price Validation

The scraper rejects values that are clearly not product prices:

• Values below €2 (star ratings, weights, dimensions)
• Whole numbers below €30 without decimals (review counts, percentages)
• Pages returning HTTP 404 or "no results" responses

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Warnings Displayed

Icon	Meaning
⚠	Shop did not include shipping cost information
✓	Free shipping detected for this shop
i	Prices loaded from cache (less than 60 minutes old)
✖	Too few prices found — try a different search query

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Supported Shops (50+)

Tier A (searched first): Plaisio, Public, Kotsovolos, e-shop.gr, You.gr, Germanos

Tier B (fallback): Electronet, Shopflix, iStorm, iSquare, PC1, MrBig, Gadget Market, HellasDigital, Techstores, TowerShop, IT Store, Cosmodata, Msystems, VisionStudio, Websupplies, Cosmote eShop, Vodafone eShop, Nova

Tier C (last resort): FixShop, data-media, batteries.gr, dot-media, MGManager, Toner Hellas, printking, G for Gadget, Oktabit, ACI Hellas, papaxaralabous, dexter, Gadgetistas, easytechnology, BatteryPro, gerasis.net, Thikishop, ITsys, Tonerworld, e-Gate, techbox, Teleparts, papirosbook