#! /bin/bash

HUGO_POSTS="${HUGO_POSTS:-"./posts"}"
RCLONE_ALIAS="${RCLONE_ALIAS:-"hugo"}"
RCLONE_CONFIG="${RCLONE_CONFIG:-./rclone.conf}"
RCLONE_FOLDER="${RCLONE_FOLDER:-"shared_from_bbarl64"}"
RCLONE_FOLDER_POSTS="${RCLONE_FOLDER_POSTS:-"posts"}"
RCLONE_FOLDER_META="${RCLONE_FOLDER_META:-"meta"}"
RCLONE_OPTS="${RCLONE_OPTS:-"--drive-shared-with-me"}"
TMPDIR="${TMPDIR:-"/tmp"}"

main() {
   flags "$@"
   #posts
   meta
}

flags() {
   set -e
   set -o pipefail
   cd "$(dirname "$BASH_SOURCE")"
}

posts() {
   local want=()
   for b64_json in $(list_posts); do
      local json="$(echo "$b64_json" | base64 --decode)"
      local filename="$(echo "$json" | jq -r .Name)"
      want+=("$(imported "$json")")
      if up_to_date "$json"; then
         log "$filename: up to date"
         continue
      fi
      log "$filename: pull"
      pull "$json"
      log "$filename: extract"
      extract "$json"
      log "$filename: import"
      import "$json"
      log "$filename: metadata"
      metadata "$json"
      rm "$(pulled "$json")"
   done
   for d in "$HUGO_POSTS"/*; do
      if  [[ ! " ${want[*]} " =~ " $d " ]]; then
         log "$d: stale, pruning"
         rm -rf "$d"
      fi
   done
}

meta() {
   for b64_json in $(list_meta); do
      echo "$b64_json" | base64 --decode | jq .
   done
   false
}

fatal() {
   log "$@"
   exit 2
}

log() {
   echo "$(date +%H:%M:%S) > $*" >&2
}

list_posts() {
   RCLONE_OPTS="$RCLONE_OPTS --drive-export-formats zip" gd list_posts
}

list_meta() {
   RCLONE_OPTS="$RCLONE_OPTS --drive-export-formats txt" gd list_meta
}

up_to_date() {
   local metadatad="$(metadatad "$1")"
   if [ -f "$metadatad" ]; then
      if [ "$1" == "$(cat "$metadatad")" ]; then
         return 0
      fi
   fi
   return 1
}

pulled() {
   echo "$TMPDIR/$(echo "$1" | jq -r .Name)"
}

pull() {
   local filename="$(echo "$json" | jq -r .Name)"
   gd pull_posts "$filename"
}

extracted() {
   local pulled_file="$(pulled "$1")"
   local date="$(echo "$1" | jq -r .ModTime)"
   date="${date%%T*}"
   local pulled_file_safe_basename="$(basename "$pulled_file" | sed 's/.zip$//' | sed 's/[^a-zA-Z0-9]/_/g')"
   echo "$TMPDIR/${date}_${pulled_file_safe_basename}"
}

extract() {
   local extracted_dir="$(extracted "$1")"
   local index_html="$extracted_dir/.index.html"
   local index_md="$extracted_dir/index.md"
   local pulled_file="$(pulled "$1")"
   local u_date_iso="$(echo "$1" | jq -r .ModTime)"

   if [ -d "$extracted_dir" ]; then
      rm -rf "$extracted_dir"
   fi
   mkdir -p "$extracted_dir"
   7z x -o"$extracted_dir" "$pulled_file"

   cat "$extracted_dir"/*.html \
      | sed 's/.*<body/<body/' \
      | sed 's/<\/body>.*/<\/body>/' \
      > "$index_html"
   local tags=($(cat "$index_html" | sed '/^$/!{s/<[^>]*>//g;p;}' | grep -o '#[a-zA-Z0-9]*' | grep '[a-zA-Z]' | sed 's/^#//' | sort -u))
   local tags_csv="$(first=false; for tag in "${tags[@]}"; do true; if $first; then echo -n ", "; fi; first=true; echo -n "$tag"; done)"

   printf '
      ---
      title: "%s"
      date: %s
      draft: false
      tags: [%s]
      ---
      ' \
      "$(basename "$pulled_file" | sed 's/.zip$//' | sed 's/"/\\"/g')" \
      "$u_date_iso" \
      "$tags_csv" \
      | sed 's/^[ ]*//' \
      | grep . \
      > "$index_md"

   cat "$index_html" >> "$index_md"
   echo "" >> "$index_md"
   rm "$index_html" "$extracted_dir"/*.html

   for ext in png jpg jpeg gif JPG; do find "$extracted_dir" -name "*.$ext"; done | while read -r line; do
      convert "$line" -ordered-dither o8x8,8,8,4 "$line.2"
      mv "$line.2" "$line"
   done
}

imported() {
   local extracted_dir="$(extracted "$1")"
   echo "$HUGO_POSTS/$(basename "$extracted_dir")"
}

import() {
   local extracted_dir="$(extracted "$1")"
   local target_dir="$(imported "$1")"
   if [ -d "$target_dir" ]; then
      rm -rf "$target_dir"
   fi
   mv "$extracted_dir" "$target_dir"
}

metadatad() {
   local imported="$(imported "$1")"
   echo "$imported"/.metadata.json
}

metadata() {
   local metadatad="$(metadatad "$1")"
   echo "$1" > "$metadatad"
}

gd() (
   list() {
      rc lsjson "$RCLONE_ALIAS:$RCLONE_FOLDER/$1" \
         | jq -c .[] \
         | grep -E '(zip|txt)"' \
         | while read -r line; do
         echo "$line" | base64
      done
   }
   list_posts() {
      gd list "$RCLONE_FOLDER_POSTS"
   }
   list_meta() {
      gd list "$RCLONE_FOLDER_META"
   }
   pull_posts() {
      rc copy "$RCLONE_ALIAS:$RCLONE_FOLDER/$RCLONE_FOLDER_POSTS/$1" "$TMPDIR"/
   }
   rc() {
      rclone \
         --config "$RCLONE_CONFIG" \
         --fast-list \
         $RCLONE_OPTS \
         "$@"
   }

   "$@"
)

if [ "$0" == "$BASH_SOURCE" ]; then
   main "$@"
fi