#!/bin/sh
DOCUMENTATION=$(cat <<END_OF_DOCUMENTATION
build.sh 1.2

Compile the entire static site (located in the same directory as this
script) using format.sh to a specified directory where it can be
served (eg. by serve.sh) or uploaded to a web server.

By default the site will be generated in the build/ directory (it will
be created if it does not exist).  Additionally, by default, files
that have not changed since the last running of build.sh will not be
re-processed.

Non-HTML files are not transformed in any way by this script.  They
are just translated into an equivalent directory in the build
directory (eg. assets/style.css -> build/assets/style.css).

HTML files are translated in two ways:
  1. non-'index.html' files are translated into their
     basename/index.html (eg. a/index.html -> a/index.html, and
     a/cool.html -> a/cool/index.html).
  2. HTML files are passed through format.sh.

The program exits immediately upon a single file failing to be
transformed/translated.

USAGE: build.sh [OPTIONS]

Where the OPTIONS are:
  --directory DIR
    Builds the files into DIR instead of the default ./build folder.
    DIR should NOT contain a trailing '/'.

  --force
    Force the status of each operation to be either OK or FAIL.
    (Remove the SKIP option.)

  --help
    Outputs this manual-style help message and immediately exits.

  --no-colour
    Strips ANSI colour codes from the output.

  --show-skipped
    Show the skipped files explicitly with a SKIP status (instead of
    no output).

  --version
    Outputs the script name along with its version number.

Requirements: Except for a single use of -nt, which is not POSIX
compliant, but is implemented in most modern shells, this script is
POSIX compliant.

SPDX-FileCopyrightText: Copyright (c) 2022, Theodore Preduta.
SPDX-License-Identifier: BSD-2-Clause
END_OF_DOCUMENTATION
)

usage() {
  [ -n "$1" ] && echo "$1" && echo

  echo "Usage: build.sh [OPTIONS]"
  echo "Try running with --help for more information."

  exit 1
}

build_dir="./build"
force="false"
explicit_skip="false"

status_ok_string="\e[32mOK\e[0m\n"
status_skip_string="\e[36mSKIP\e[0m\n"
status_fail_string="\e[31mFAIL\e[0m\n"

while [ ! "$*" = "" ]; do
  case "$1" in
    --base-url)
      base_url="$2"
      shift 2;;
    --directory)
      build_dir="$2"
      shift 2;;
    --force)
      force="true"
      shift 1;;
    --help)
      echo "$DOCUMENTATION"
      exit 0;;
    --no-colour)
      status_ok_string="OK\n"
      status_skip_string="SKIP\n"
      status_fail_string="FAIL\n"
      shift 1;;
    --show-skipped)
      explicit_skip=true
      shift 1;;
    --version)
      echo "$DOCUMENTATION" | head -n 1
      exit 0;;
    *)
      usage "Unkown argument: $1";;
  esac
done

status_start() { printf "%s '%s' -> '%s'..." "$1" "$2" "$3"; }
status_ok()    { printf "$status_ok_string"; }
status_skip()  { printf "$status_skip_string"; }
status_fail()  { printf "$status_fail_string"; }

process_file() {
  from="$1"
  to_dir=""
  to_name=""
  action=""
  location=""

  case "$from" in
    index.html|*/index.html)
      action="Formatting"
      to_name="index.html"
      to_dir="$build_dir/${from%/index.html}";;
    *.html)
      action="Formatting"
      to_name="index.html"
      to_dir="$build_dir/${from%.html}";;
    *)
      action="Copying"
      to_name="$(basename "$from")"
      to_dir="$build_dir/${from%/$to_name}";;
  esac

  if [ "$to_dir/$to_name" -nt "$from" ] && [ "$force" != "true" ]; then
    if [ "$explicit_skip" != "false" ]; then
      status_start "$action" "$from" "$to_dir/$to_name"
      status_skip
    fi

    return 0
  fi

  status_start "$action" "$from" "$to_dir/$to_name"

  out="$(mkdir -p "$to_dir" 2>&1)"
  if [ ! "$out" = "" ]; then
    status_fail
    echo "ERROR in $out"
    exit 1
  fi

  case "$to_name" in
    *.html)
      ./format.sh --location "${to_dir#$build_dir/.}/" < "$from" > "$to_dir/$to_name"
      code="$?"
      case "$code" in
        0) status_ok;;
        1) status_fail; echo "ERROR in format.sh: catastrophic failure.";     exit 1;;
        2) status_ok;   echo "WARNING in format.sh: File just copied.";;
        3) status_fail; echo "ERROR in format.sh: Open meta block.";          exit 1;;
        4) status_fail; echo "ERROR in format.sh: Unkown meta block option."; exit 1;;
        *) status_fail; echo "ERROR in format.sh: Unknown error.";            exit 1;;
      esac;;
    *)
      out="$(cp "$from" "$to_dir/$to_name" 2>&1)"
      if [ ! "$out" = "" ]; then
        status_fail
        echo "ERROR in $out"
        exit 1
      else
        status_ok
      fi;;
  esac
}

find . \( -path "$build_dir" -prune \) \
     -o \( -type f -print \) | while read -r file
do
  process_file "$file"
done