#!/usr/bin/env bash
# Export all Immich assets for given accounts within a date range.
# Usage: immich-export
# Accounts and API keys are hardcoded below; output goes to DEST_DIR.
#
# Works in two phases per account:
#   1. Discovery — paginate through all search results and collect asset IDs
#   2. Download  — fetch each asset with real [X/total] progress

set -euo pipefail

IMMICH_URL="http://immich.f3s.lan.buetow.org"
DEST_DIR="/home/paul/Pictures/Pictures.Processing"
DATE_AFTER="2026-01-01T00:00:00.000Z"
DATE_BEFORE="2026-03-31T23:59:59.000Z"
PAGE_SIZE=100

# Load keys explicitly — declare -A with inline $() substitutions can silently
# drop entries in some bash versions, so we assign after the declaration.
declare -A ACCOUNTS
ACCOUNTS["paul"]="$(cat ~/.immich_paul_key)"
ACCOUNTS["albena"]="$(cat ~/.immich_albena_key)"

mkdir -p "$DEST_DIR"

# Phase 1: paginate through all search results and print "id\tfilename" lines.
# The API's 'total' field only reflects the current page size, not the grand
# total, so we must walk all pages to know how many assets there are.
discover_assets() {
  local api_key="$1"
  local page=1

  while true; do
    local response
    response=$(curl -sf -X POST "$IMMICH_URL/api/search/metadata" \
      -H "x-api-key: $api_key" \
      -H "Content-Type: application/json" \
      -d "{\"takenAfter\":\"$DATE_AFTER\",\"takenBefore\":\"$DATE_BEFORE\",\"type\":\"IMAGE\",\"size\":$PAGE_SIZE,\"page\":$page}")

    # Print id<TAB>filename for each asset on this page
    echo "$response" | python3 -c "
import json, sys
d = json.load(sys.stdin)
for item in d['assets']['items']:
    print(item['id'] + '\t' + item['originalFileName'])
"
    # Use 'or ""' to handle null nextPage — .get() returns None when the key
    # exists with a JSON null value, and print(None) would yield "None" (non-empty).
    local next_page
    next_page=$(echo "$response" | python3 -c "import json,sys; d=json.load(sys.stdin); print(d['assets'].get('nextPage') or '')")

    echo "    Discovery: page $page done..." >&2
    [[ -z "$next_page" ]] && break
    page="$next_page"
  done
}

# Phase 2: download each asset by ID, showing real [X/total] progress.
download_assets() {
  local api_key="$1"
  local account_dir="$2"
  local asset_list="$3"   # path to temp file with "id\tfilename" lines
  local total
  total=$(wc -l < "$asset_list")
  local downloaded=0
  local skipped=0
  local n=0

  while IFS=$'\t' read -r asset_id filename; do
    ((n++)) || true
    local dest="$account_dir/$filename"

    if [[ -f "$dest" ]]; then
      ((skipped++)) || true
      echo "    [$n/$total] skip (exists): $filename"
      continue
    fi

    # Download to a temp file first; rename to final dest only on success.
    # This prevents half-downloaded files from being mistaken as complete.
    local tmp="$dest.tmp"
    if curl -sf -o "$tmp" \
      -H "x-api-key: $api_key" \
      "$IMMICH_URL/api/assets/$asset_id/original"; then
      mv "$tmp" "$dest"
      ((downloaded++)) || true
      echo "    [$n/$total] downloaded: $filename"
    else
      echo "    [$n/$total] ERROR: failed to download $asset_id ($filename)" >&2
      rm -f "$tmp"    # Remove partial temp file on failure
    fi
  done < "$asset_list"

  echo "    Done: $downloaded downloaded, $skipped skipped (already exist)"
}

download_assets_for_account() {
  local account="$1"
  local api_key="$2"
  local account_dir="$DEST_DIR/$account"
  mkdir -p "$account_dir"

  echo "==> Account: $account"

  # Collect full asset list into a temp file so we know the total upfront
  local asset_list
  asset_list=$(mktemp)
  trap "rm -f $asset_list" EXIT

  echo "    Phase 1: discovering assets..."
  discover_assets "$api_key" > "$asset_list"
  echo "    Found $(wc -l < "$asset_list") images total"

  # Clean up any leftover .tmp files from a previously aborted run
  local stale_tmp
  stale_tmp=$(find "$account_dir" -name "*.tmp" 2>/dev/null | wc -l)
  if [[ "$stale_tmp" -gt 0 ]]; then
    echo "    Cleaning up $stale_tmp leftover .tmp file(s) from previous run..."
    find "$account_dir" -name "*.tmp" -delete
  fi

  echo "    Phase 2: downloading..."
  download_assets "$api_key" "$account_dir" "$asset_list"

  rm -f "$asset_list"
  trap - EXIT
}

for account in "${!ACCOUNTS[@]}"; do
  download_assets_for_account "$account" "${ACCOUNTS[$account]}"
done

echo ""
echo "Export complete -> $DEST_DIR"