#!/usr/bin/env bash

set -e
set -u

# This script compares the table of supported tools in both the README file
# and the doc/ale.txt file, so we can complain if they don't match up.

# Find the start and end lines for the help section.
ale_help_start_line="$( \
    grep -m1 -n '^[0-9][0-9]*\. *Supported Languages' doc/ale.txt \
    | sed 's/\([0-9]*\).*/\1/' \
)"
ale_help_section_size="$( \
    tail -n +"$ale_help_start_line" doc/ale.txt \
    | grep -m1 -n '================' \
    | sed 's/\([0-9]*\).*/\1/' \
)"
# -- shellcheck complains about expr, but it works better.
# shellcheck disable=SC2003
ale_help_end_line="$(expr "$ale_help_start_line" + "$ale_help_section_size")"

# Find the start and end lines for the same section in the README.
readme_start_line="$( \
    grep -m1 -n '^.*[0-9][0-9]*\. *Supported Languages' .github/README.md \
    | sed 's/\([0-9]*\).*/\1/' \
)"
readme_section_size="$( \
    tail -n +"$readme_start_line" .github/README.md \
    | grep -m1 -n '^##.*Usage' \
    | sed 's/\([0-9]*\).*/\1/' \
)"
# shellcheck disable=SC2003
readme_end_line="$(expr "$readme_start_line" + "$readme_section_size")"

doc_file="$(mktemp -t doc.XXXXXXXX)"
readme_file="$(mktemp -t readme.XXXXXXXX)"

sed -n "$ale_help_start_line,$ale_help_end_line"p doc/ale.txt \
    | grep '\* .*: ' \
    | sed 's/^*//' \
    | sed 's/[`!^]//g;s/([^)]*)//g' \
    | sed 's/ *\([,:]\)/\1/g' \
    | sed 's/  */ /g' \
    | sed 's/^ *//;s/ *$//' \
    | sed 's/^/ /' \
    > "$doc_file"

sed -n "$readme_start_line,$readme_end_line"p .github/README.md \
    | grep '| .* |' \
    | sed '/^| Language/d;/^| ---/d' \
    | sed 's/^|//' \
    | sed 's/ \{0,1\}|/:/' \
    | sed 's/[`!^|]//g;s/([^)]*)//g' \
    | sed 's/\[//g;s/\]//g' \
    | sed 's/see[^,]*//g' \
    | sed 's/ *\([,:]\)/\1/g' \
    | sed 's/  */ /g' \
    | sed 's/^ *//;s/ *$//' \
    | sed 's/^/ /' \
    | sed 's/ *-n flag//g' \
    > "$readme_file"

exit_code=0

diff -U0 "$readme_file" "$doc_file" || exit_code=$?

rm "$doc_file"
rm "$readme_file"

exit "$exit_code"