#!/usr/bin/env bash

set -euo pipefail

shopt -s nullglob

fail() {
    echo "Failure: $@"
    exit 1
}

lint() {
    local spec=$1

    echo "Linting (luarocks)..."

    if ! luarocks lint "$spec"; then
        fail "luarocks lint returned error"
    fi

    echo "Linting (luacheck)..."

    # luacheck helps to point out some semantic issues (like duplicate
    # table keys)
    if ! luacheck \
        --quiet \
        --no-global \
        -- - \
        < "$spec";
    then
        fail "luacheck returned error"
    fi
}

read_modules() {
    local spec="$1"
    resty -e '
        local fn = loadstring(io.stdin:read("*a"))
        local rock = {}
        setfenv(fn, rock)
        fn()

        for mod, fname in pairs(rock.build.modules) do
            print(fname .. "|" .. mod)
        end
    ' < "$spec"
}

check_modules() {
    local spec=$1
    local -A files=()

    echo "Checking modules..."

    local failed=0

    for line in $(read_modules "$spec"); do
        fname=${line%|*}
        module=${line#*|}

        files[$fname]="$module"

        if [[ ! -f $fname ]]; then
            : $(( failed++ ))
            echo "Module ($module) file ($fname) is missing"
        fi
    done

    for fname in $(git ls-files 'kong/*.lua'); do
        if [[ -z ${files[$fname]:-} ]]; then
            : $(( failed++ ))
            echo "File ($fname) not found in rockspec ($spec)"
        fi
    done

    if (( failed > 0 )); then
        fail "rockspec build.modules is invalid"
    fi
}


main() {
    local files=(kong-*.rockspec)
    local spec

    if (( ${#files[@]} == 0 )); then
        fail "no rockspec file found"

    elif (( ${#files[@]} > 1 )); then
        fail "multiple rockspec files found: ${files[*]}"

    else
        spec=${files[0]}
    fi

    if [ "$spec" = "kong-latest.rockspec" ]; then
        version=$(grep -E '^\s*(major|minor|patch)\s*=' kong/meta.lua \
            | sed -E 's/[^0-9]*([0-9]+).*/\1/' \
            | paste -sd. -)
        cp "$spec" "kong-$version-0.rockspec"
        sed -i "s/^version *= *\".*\"/version = \"$version-0\"/" "kong-$version-0.rockspec"
        spec=kong-$version-0.rockspec
    fi

    echo "Found rockspec file to validate: $spec"

    lint "$spec"

    check_modules "$spec"

    echo "OK!"
}


main "$@"