#!/bin/bash
set -e
set -o pipefail

# Calculate yesterday's date in YYYY-MM-DD format
YESTERDAY=$(date -d "yesterday" +%Y-%m-%d)
echo "Starting price tracking for $YESTERDAY" >&2

# Helper function to perform HTTP requests with retries
# Usage: make_request <retries> <method> <url> [data] [header1] [header2] ...
make_request() {
    local retries=$1
    local method=$2
    local url=$3
    local data=$4
    shift 4
    local headers=("$@")

    local count=0
    local wait_time=3
    local response

    while [ "$count" -lt "$retries" ]; do
        local curl_opts=(-s -S -f -X "$method")

        if [ -n "$data" ]; then
            curl_opts+=(-d "$data")
        fi

        for h in "${headers[@]}"; do
            curl_opts+=(-H "$h")
        done

        if response=$(curl "${curl_opts[@]}" "$url"); then
            echo "$response"
            return 0
        fi

        echo "Request to $url failed (Attempt $((count+1))/$retries). Retrying in ${wait_time}s..." >&2
        sleep "$wait_time"
        count=$((count + 1))
    done

    echo "ERROR: Request to $url failed after $retries attempts" >&2
    return 1
}

# Fetch and process rates for a fiat currency
get_price_data() {
    local currency=$1
    local data avg open24 last

    if data=$(make_request 3 "GET" "https://www.bitstamp.net/api/v2/ticker/btc${currency,,}/" ""); then
        echo "Successfully retrieved ${currency} price data" >&2
        open24=$(echo "$data" | jq -r '.open_24')
        last=$(echo "$data" | jq -r '.last')
        avg=$(echo "$open24 $last" | awk '{printf "%.0f", ($1 + $2) / 2}')
        echo $avg
    else
        echo "ERROR: Failed to retrieve ${currency} price data" >&2
        return 1
    fi
}

# Get price data for each currency
usd_avg=$(get_price_data "USD") || exit 1
eur_avg=$(get_price_data "EUR") || exit 1
gbp_avg=$(get_price_data "GBP") || exit 1

# Create JSON
json=$(jq -n \
  --argjson eur "$eur_avg" \
  --argjson usd "$usd_avg" \
  --argjson gbp "$gbp_avg" \
  '{"EUR": $eur, "USD": $usd, "GBP": $gbp}')
echo "Rates: $json" >&2

# PUT in remote storage
if make_request 3 "PUT" "<%= @rs_base_url %>/$YESTERDAY" "$json" \
    "Authorization: Bearer $RS_AUTH" \
    "Content-Type: application/json" > /dev/null; then
   echo "Successfully uploaded price data" >&2
else
   echo "ERROR: Failed to upload price data" >&2
   exit 1
fi