# Project Specification: Territory Address Combiner

This document outlines the plan for developing a script to assign Territory IDs to addresses based on their geographic coordinates.

## 1. Project Setup & File I/O [x]

1.1. Read the `TerritoryExport.csv` file. [x]
1.2. Parse the CSV data into a list of objects, where each object represents a territory and contains its ID and boundary points. [x]
1.3. Read the `Addresses.csv` file. [x]
1.4. Parse the CSV data into a list of objects, where each object represents an address and its properties, including latitude and longitude. [x]

## 2. Data Processing and Structuring [x]

2.1. For each territory, parse the `Boundary` string into a numerical list of coordinate pairs. Each pair will represent a vertex of the polygon. [x]
2.2. For each address, ensure its `Latitude` and `Longitude` are stored as numerical data types. [x]

## 3. Core Logic: Point-in-Polygon (PIP) Implementation [x]

3.1. Create a function that implements the Ray Casting algorithm to determine if a point is inside a polygon. [x]
3.2. This function will accept two arguments: the coordinates of the address (the point) and the list of vertices for a territory boundary (the polygon). [x]
3.3. The function will return `true` if the point is inside the polygon and `false` otherwise. [x]

## 4. Territory Assignment [x]

4.1. Iterate through each address in the parsed list from `Addresses.csv`. [x]
4.2. For each address, iterate through each territory from the parsed list from `TerritoryExport.csv`. [x]
4.3. Use the PIP function (from step 3) to check if the address's coordinate is inside the current territory's boundary. [x]
4.4. If the PIP function returns `true`:
    4.4.1. Assign the territory's `TerritoryID` to the `TerritoryID` field of the address object. [x]
    4.4.2. Break the inner loop (territory iteration) and proceed to the next address. [x]

## 5. Output Generation [x]

5.1. Create a new file named `Addresses_Updated.csv`. [x]
5.2. Write the header row from the original `Addresses.csv` to the new file. [x]
5.3. Iterate through the updated list of address objects. [x]
5.4. For each address object, write a new row to `Addresses_Updated.csv` with all the original data plus the newly assigned `TerritoryID`. [x]

## 6. Finalization [x]

6.1. Close any open file streams. [x]
6.2. Report successful completion to the user. [x]