#!/bin/bash

set -e

parser_dir="$(pwd)"

. $parser_dir/scripts/common.sh

if [ -z "$1" ]; then
  repos=$(cat $top_repositories)
  echo "Running on all top repositories."
else
  repos=$(sed "$1q;d" $top_repositories)
  echo "Running on single repository $repos."
fi

# Function to validate that a passed-in git repository can be parsed using this parser.
#
# If the passed-in repository fails to parse in ways that do not match the `known_failures` script
# data, this prints info about the failure and exits the script with a nonzero status code.
function validate() {
  repo=$1; url=$2; tag=$3; part=$4; total=$5

  if [ -z "$part" ] || [ -z "$total" ]; then
    part=0
    total=1
  fi

  data_dir=$tmpdir/.$repo-data-$part
  mkdir -p $data_dir || true

  # Find the start and end of this section based on the passed-in `part` and `total`.
  all_files=$data_dir/all_files.txt
  swift_files_under "$tmpdir/$repo" > $all_files
  file_count=$(wc -l < $all_files | tr -d ' ')

  one_past_the_end=$((file_count + 1))
  start=$(($((one_past_the_end * part)) / total))
  next_part=$((part + 1))
  next_start=$(($((one_past_the_end * next_part)) / total))
  end=$((next_start - 1))
  len=$((end - start))

  failed_files=$(
    IFS=$'\n'
    for file in $(head -$end < $all_files | tail -$len); do
       npx tree-sitter parse -q "$file" 2>/dev/null
    done | { grep -v -f "$known_failures" || true; }
    unset IFS
  )

  if [[ "$failed_files" = *[![:space:]]* ]]; then
    echo -en "Unexpected parse failure found in $repo "
    if [ -z $4 ]; then
        echo ":"
    else
        echo "block $start-$end:"
    fi

    cat <<<"$failed_files"

    exit 1
  elif [ -z $4 ]; then
    echo "Parsed $repo successfully!"
  else
    echo "Parsed $repo files $start-$end of $file_count successfully!"
  fi
}

# It's really easy to add a blank line to `known_failures.txt`, which will make everything pass.
# This echoes some string from random.org to prove that the grp isn't excluding everything. If we
# added a blank line, this would have zero items, which results in a nonzero exit code from grep.
if ! echo "vkDSrg8n" | grep -v -f "$known_failures" > /dev/null; then
  echo "You added a blank line to known_failures!"
  exit 1
fi

# Run `validate` on every repository in `top-repositories` sequentially.
while read line ; do
    cd $tmpdir
    checkout $line

    cd $parser_dir
    if [ -z "$1" ]; then
        validate $line &
        pids+=($!)
    else
        validate $line
    fi
done <<<"$repos"

if [ -z "$1" ]; then
    for pid in "${pids[@]}" ; do
        wait $pid
    done
fi