#!/bin/bash

if [[ -z "${1}" ]]; then
  echo "Must give Bash filename..." >&2
  echo "Example:" >&2
  echo "  $0 bashscript.sh" >&2
  exit 1
fi

if [[ ${1: -3} != ".sh" ]]; then
  echo "Bash file ${1} does not have a .sh extension..." >&2
  exit 2
fi

if [[ -f "${1}" ]]; then
  bashscript="${1}"
else
  echo "Bash file ${1} does not exist..." >&2
  exit 3
fi

declaration="$(head -1 "${bashscript}")"

if [[ ${declaration: -5} != '/bash' ]]; then
  echo "Bash file ${bashscript} does not invoke Bash binary..." >&2
  exit 4
fi

pathtobash="${declaration:2}"

if [[ ! -f "${pathtobash}" ]]; then
  echo "Bash file ${bashscript} invokes Bash binary at invalid location ${pathtobash}..." >&2
  exit 5
fi

builddatetime="$(date "+%y%m%d%H%M")"
builddatestring="$(date)"

bashscriptfile="${bashscript##*/}"
bashscriptpath="${bashscript%/*}"
if [[ -z "${bashscriptpath}" || "${bashscriptpath}" == "${bashscriptfile}" ]]; then
  bashscriptpath="."
fi

if [[ ! -f "${bashscriptpath}/build.count" ]]; then
  buildcount=1
else
  buildcount=$(head -1 "${bashscriptpath}/build.count")
#######################################################
# Add Regex to check buildcount is an integer about 0 #
#######################################################
  ((buildcount++))
fi
echo ${buildcount} > "${bashscriptpath}/build.count"
buildfile="${bashscriptfile%.*}"
buildpath="./build-${builddatetime}-${buildcount}"

echo "Reading ${bashscriptfile}"
echo "Project path ${bashscriptpath}"
echo "Build number ${buildcount}"
echo "Build date and time ${builddatetime}"
echo "Build path ${buildpath}"
echo "Writing to ${buildfile}"

isstart=true

mkdir -p "${buildpath}"
while IFS= read -r line; do
  if [[ ${isstart} == true ]]; then
    echo "${line}" > "${buildpath}/${buildfile}"
    echo "## Built on ${builddatestring}" >> "${buildpath}/${buildfile}"
    echo "## Source script ${bashscriptfile}" >> "${buildpath}/${buildfile}"
    echo "## Project path ${bashscriptpath}" >> "${buildpath}/${buildfile}"
    echo "## Build number ${buildcount}" >> "${buildpath}/${buildfile}"
    echo "## Build path ${buildpath}" >> "${buildpath}/${buildfile}"
    echo "## Build file ${buildfile}" >> "${buildpath}/${buildfile}"
    echo >> "${buildpath}/${buildfile}"
    isstart=false
  else
    if [[ "$line" =~ ^[[:space:]]*source[[:space:]]+([^[:space:]]+\.lib\.sh)[[:space:]]*$ ]]; then
      library="${BASH_REMATCH[1]}"
    #if [[ ${line} =~ ^source && ${line} =~ \.lib\.sh$ ]]; then
    #  library="${line:7}"
      if [[ -f "${bashscriptpath}/${library}" ]]; then
        echo "Importing library ${library} from path ${bashscriptpath}"
        cat "${bashscriptpath}/${library}" >> "${buildpath}/${buildfile}"
        echo >> "${buildpath}/${buildfile}"
      else
        echo "Library ${library} not found at ${bashscriptpath}"
        echo "Build failed!"
        exit 6
      fi
    else
      echo "${line}" >> "${buildpath}/${buildfile}"
    fi
  fi
done < "${bashscript}"
chmod +x "${buildpath}/${buildfile}"
echo "Build complete!"