#!/bin/sh
# Fails if a *.rs file under ROOT/crates names a docs/runbook.md#anchor that
# has no matching `## <anchor>` line in ROOT/docs/runbook.md.
# Files under any target/ directory are ignored. Test files count.
ROOT="${1:-.}"

if [ ! -d "$ROOT/crates" ]; then
    echo "check-runbook: $ROOT/crates is not a directory" >&2
    exit 1
fi
if [ ! -f "$ROOT/docs/runbook.md" ]; then
    echo "check-runbook: $ROOT/docs/runbook.md is not a file" >&2
    exit 1
fi

work=$(mktemp -d)
if [ $? -ne 0 ] || [ -z "$work" ]; then
    echo "check-runbook: mktemp failed" >&2
    exit 1
fi
trap 'rm -rf "$work"' EXIT

find "$ROOT/crates" -type d -name target -prune -o -type f -name '*.rs' -print \
    > "$work/files"
if [ $? -ne 0 ]; then
    echo "check-runbook: find failed" >&2
    exit 1
fi

: > "$work/pointers"
while IFS= read -r f; do
    if [ ! -r "$f" ]; then
        echo "check-runbook: cannot read $f" >&2
        exit 1
    fi
    awk '{
        s = $0
        while (match(s, /docs\/runbook\.md#[A-Za-z0-9_-]*/)) {
            printf "%s\t%s\n", substr(s, RSTART + 16, RLENGTH - 16), FILENAME
            s = substr(s, RSTART + RLENGTH)
        }
    }' "$f" >> "$work/pointers"
    if [ $? -ne 0 ]; then
        echo "check-runbook: awk failed on $f" >&2
        exit 1
    fi
done < "$work/files"

if [ ! -s "$work/pointers" ]; then
    echo "check-runbook: no pointer found" >&2
    exit 1
fi

sort "$work/pointers" > "$work/sorted"
if [ $? -ne 0 ]; then
    echo "check-runbook: sort failed" >&2
    exit 1
fi

awk -F '\t' '{ print $1 }' "$work/sorted" > "$work/col1"
if [ $? -ne 0 ]; then
    echo "check-runbook: awk failed" >&2
    exit 1
fi
sort -u "$work/col1" > "$work/anchors"
if [ $? -ne 0 ]; then
    echo "check-runbook: sort failed" >&2
    exit 1
fi

status=0
while IFS= read -r anchor; do
    awk -F '\t' -v a="$anchor" '$1 == a { print $2 }' "$work/sorted" > "$work/hits"
    if [ $? -ne 0 ]; then
        echo "check-runbook: awk failed" >&2
        exit 1
    fi
    sort -u "$work/hits" > "$work/hitfiles"
    if [ $? -ne 0 ]; then
        echo "check-runbook: sort failed" >&2
        exit 1
    fi
    files=""
    while IFS= read -r hf; do
        if [ -n "$files" ]; then
            files="$files $hf"
        else
            files="$hf"
        fi
    done < "$work/hitfiles"

    if [ -z "$anchor" ]; then
        echo "check-runbook: empty anchor in $files" >&2
        status=1
        continue
    fi

    grep -q -x -F -e "## $anchor" "$ROOT/docs/runbook.md"
    g=$?
    if [ "$g" -eq 0 ]; then
        continue
    fi
    if [ "$g" -eq 1 ]; then
        echo "check-runbook: no entry for $anchor (in $files)" >&2
        status=1
        continue
    fi
    echo "check-runbook: grep failed" >&2
    exit 1
done < "$work/anchors"

exit "$status"