#!/usr/bin/env bash
# OpenTripPlanner data setup script for Greater London
# Downloads OSM extract and TfL GTFS feeds for transit routing.
#
# Usage:
#   ./scripts/otp-setup.sh [DATA_DIR]
#
# DATA_DIR defaults to ./otp-data/
# The directory is suitable for mounting as /var/opentripplanner in OTP container.

set -euo pipefail

DATA_DIR="${1:-./otp-data}"
GEOFABRIK_URL="https://download.geofabrik.de/europe/great-britain/england/greater-london-latest.osm.pbf"
OSM_FILE="greater-london-latest.osm.pbf"

# TfL GTFS feeds (Bus Open Data Service + TfL open data)
# These URLs may need updating; check https://data.bus-data.dft.gov.uk/ and TfL API
TFL_GTFS_URLS=(
    "https://data.bus-data.dft.gov.uk/timetable/download/gtfs-file/london/"
)

echo "==> OTP Setup for Greater London"
echo "    Data directory: ${DATA_DIR}"

mkdir -p "${DATA_DIR}"

# Download OSM extract
if [ ! -f "${DATA_DIR}/${OSM_FILE}" ]; then
    echo "==> Downloading Greater London OSM extract..."
    curl -L -o "${DATA_DIR}/${OSM_FILE}" "${GEOFABRIK_URL}"
else
    echo "==> OSM extract already downloaded"
fi

# Download GTFS feeds
for i in "${!TFL_GTFS_URLS[@]}"; do
    GTFS_FILE="gtfs-london-${i}.zip"
    if [ ! -f "${DATA_DIR}/${GTFS_FILE}" ]; then
        echo "==> Downloading GTFS feed ${i}..."
        curl -L -o "${DATA_DIR}/${GTFS_FILE}" "${TFL_GTFS_URLS[$i]}" || {
            echo "    WARNING: Failed to download GTFS feed from ${TFL_GTFS_URLS[$i]}"
            echo "    You may need to manually download GTFS data."
            echo "    Check: https://data.bus-data.dft.gov.uk/"
            echo "    Place .zip files in ${DATA_DIR}/"
        }
    else
        echo "==> GTFS feed ${i} already downloaded"
    fi
done

# Create OTP build config if not present
if [ ! -f "${DATA_DIR}/build-config.json" ]; then
    echo "==> Creating OTP build config..."
    cat > "${DATA_DIR}/build-config.json" << 'EOF'
{
  "osm": [
    {
      "source": "greater-london-latest.osm.pbf"
    }
  ],
  "transitFeeds": [
    {
      "type": "gtfs",
      "source": "gtfs-london-0.zip"
    }
  ]
}
EOF
fi

# Create OTP router config if not present
if [ ! -f "${DATA_DIR}/router-config.json" ]; then
    echo "==> Creating OTP router config..."
    cat > "${DATA_DIR}/router-config.json" << 'EOF'
{
  "routingDefaults": {
    "walkSpeed": 1.3,
    "bikeSpeed": 5.0,
    "numItineraries": 3
  }
}
EOF
fi

echo ""
echo "==> OTP setup complete!"
echo "    Mount ${DATA_DIR} as /var/opentripplanner in OTP container."
echo ""
echo "    OTP will build the transit graph on first startup (~2 min for London)."
echo ""
echo "    Example:"
echo "      docker run -p 8080:8080 -v ${DATA_DIR}:/var/opentripplanner \\"
echo "        opentripplanner/opentripplanner:2.6.0 --load --serve"