#!/bin/bash

# Error handling
set -eo pipefail
trap 'echo "❌ Error occurred on line $LINENO. Exiting..."; exit 1' ERR

# Function to display error messages
error_msg() {
    echo "❌ Error: $1" >&2
    exit 1
}

# Check if input file is provided
if [ $# -ne 1 ]; then
    error_msg "Usage: $0 <csv_file>"
fi

INPUT_FILE="$1"

# Validate input file exists and is readable
[ ! -f "$INPUT_FILE" ] && error_msg "Input file '$INPUT_FILE' does not exist!"
[ ! -r "$INPUT_FILE" ] && error_msg "Input file '$INPUT_FILE' is not readable!"

# Create temporary file for processing
TEMP_FILE=$(mktemp)
trap 'rm -f "$TEMP_FILE"' EXIT

# Check if ollama is installed
command -v ollama >/dev/null 2>&1 || error_msg "ollama is not installed!"

# Process the CSV file
while IFS=, read -r chargeName remainder || [ -n "$chargeName" ]; do
    # Skip empty lines
    [ -z "$chargeName" ] && continue

    # Remove any trailing/leading whitespace
    chargeName=$(echo "$chargeName" | sed -e 's/^[[:space:]]*//' -e 's/[[:space:]]*$//')

    # Skip if first column is empty
    [ -z "$chargeName" ] && continue

    echo "🔄 Processing charge: $chargeName"

    # Call ollama and capture output, then remove commas
    aiDesc=$(printf '%s' "$chargeName" | ollama run granite3.1-dense:latest "interpret what this credit card charge description might be in simple, plain English. Use no more than three sentences: $chargeName" 2>/dev/null | tr -d ',' || echo "AI processing failed")

    # If AI processing failed, add error message
    if [ "$aiDesc" = "AI processing failed" ]; then
        echo "⚠️ Warning: Failed to process '$chargeName'"
    fi

    # Properly escape the AI description for sed
    aiDesc_escaped=$(printf '%s\n' "$aiDesc" | sed 's/[\/&]/\\&/g')

    # Write the processed line to temp file
    printf '%s,%s\n' "$chargeName" "$aiDesc" >> "$TEMP_FILE"

    echo "✅ Processed entry successfully"
done < "$INPUT_FILE"

# Move temp file to original file
mv "$TEMP_FILE" "$INPUT_FILE"

# **Apply regex fix to remove stray newline followed by a double quote**
# _Using perl for reliable multiline regex handling_
perl -i -0777 -pe 's/\n"/,\n/g' "$INPUT_FILE"

# Display success message with some flair
cat << "EOF"
✨✨✨✨✨✨✨✨✨✨✨✨✨✨✨✨✨
🎉 CSV Processing Complete! 🎉
✨ All entries have been processed
🔍 AI descriptions have been added
💾 File has been updated successfully
✨✨✨✨✨✨✨✨✨✨✨✨✨✨✨✨✨
EOF