#!/usr/bin/env bash

set -euo pipefail

TOOL_NAME="cleanup_garmin_varia_media_folder.sh"

DEFAULT_MEDIA_ROOT="."

MAX_APPLEDOUBLE_BYTES=4096

DRY_RUN=false

VERBOSE=false

MEDIA_ROOT="$DEFAULT_MEDIA_ROOT"

TMP_MP4_LIST=""

TMP_ACTIONS=""

TMP_NONSTANDARD=""

TMP_ZERO=""

TMP_BLOCKED=""

TMP_APPLE=""

APPLE_ARTIFACTS_REMOVED=0

ZERO_SIZE_REMOVED=0

NONSTANDARD_REMOVED=0

RENAMES_DONE=0

BLOCKED_GROUPS=0

BLOCKED_FILES=0

usage() {

  cat <<'EOF'

Usage:

  cleanup_garmin_varia_media_folder.sh [options] [MEDIA_ROOT]

Purpose:

  Clean common Apple artifacts and zero-size MP4 files, then normalize

  duplicate MP4 names produced during copy/import retries.

Rules:

  - Delete AppleDouble sidecars matching ._* only when size <= 4096 bytes

  - Delete zero-size .mp4 files

  - For canonical timestamp names:

      YYYY-MM-DD_HH-MM-SS.mp4

      YYYY-MM-DD_HH-MM-SS_<n>.mp4

    if exactly one suffixed duplicate exists and the base file is missing,

    rename duplicate to base name

  - If base exists, or multiple suffixed duplicates exist, keep files unchanged

    and report them as blocked

Options:

  --dry-run         Print actions without changing files

  --verbose         Print per-file operations

  -h, --help        Show this help

Examples:

  ./cleanup_garmin_varia_media_folder.sh --dry-run ~/Autofs/xdev/autonas/ext01/@Camera/import

  ./cleanup_garmin_varia_media_folder.sh ~/Autofs/xdev/is-baobab/nvme0n1/@backup/Garmin

EOF

}

log_msg() {

  local level="$1"

  shift

  printf '[%s] [%s] %s\n' "$(date '+%Y-%m-%d %H:%M:%S')" "$level" "$*"

}

vlog_msg() {

  if [[ "$VERBOSE" == true ]]; then

    log_msg "INFO" "$*"

  fi

}

die() {

  log_msg "ERROR" "$*"

  exit 2

}

cleanup_tmp_files() {

  rm -f -- "$TMP_MP4_LIST" "$TMP_ACTIONS" "$TMP_NONSTANDARD" "$TMP_ZERO" "$TMP_BLOCKED" "$TMP_APPLE" "$TMP_ACTIONS.tmp" 2>/dev/null || true

}

parse_args() {

  while [[ $# -gt 0 ]]; do

    case "$1" in

      --dry-run)

        DRY_RUN=true

        shift

        ;;

      --verbose)

        VERBOSE=true

        shift

        ;;

      -h|--help)

        usage

        exit 0

        ;;

      -*)

        die "Unknown option: $1"

        ;;

      *)

        MEDIA_ROOT="$1"

        shift

        ;;

    esac

  done

}

init_tmp_files() {

  TMP_MP4_LIST="$(mktemp)"

  TMP_ACTIONS="$(mktemp)"

  TMP_NONSTANDARD="$(mktemp)"

  TMP_ZERO="$(mktemp)"

  TMP_BLOCKED="$(mktemp)"

  TMP_APPLE="$(mktemp)"

  trap cleanup_tmp_files EXIT

}

validate_media_root() {

  [[ -d "$MEDIA_ROOT" ]] || die "Media root not found: $MEDIA_ROOT"

}

rescan_mp4_files() {

  find "$MEDIA_ROOT" -type f -name '*.mp4' | sort > "$TMP_MP4_LIST"

}

safe_remove_file() {

  local path="$1"

  if [[ "$DRY_RUN" == true ]]; then

    return 0

  fi

  rm -f -- "$path"

}

remove_apple_artifacts() {

  local file size

  while IFS= read -r file; do

    [[ -n "$file" ]] || continue

    size="$(wc -c < "$file" | tr -d ' ')"

    if [[ "$size" =~ ^[0-9]+$ ]] && [[ "$size" -le "$MAX_APPLEDOUBLE_BYTES" ]]; then

      APPLE_ARTIFACTS_REMOVED=$((APPLE_ARTIFACTS_REMOVED + 1))

      printf '%s\n' "$file" >> "$TMP_APPLE"

      vlog_msg "Apple artifact: $file (${size} bytes)"

      safe_remove_file "$file"

    else

      vlog_msg "Skipped ._* larger than threshold: $file (${size} bytes)"

    fi

  done < <(find "$MEDIA_ROOT" -type f -name '._*' | sort)

  if [[ "$APPLE_ARTIFACTS_REMOVED" -gt 0 ]]; then

    if [[ "$DRY_RUN" == true ]]; then

      log_msg "INFO" "Would remove $APPLE_ARTIFACTS_REMOVED Apple artifact file(s)"

    else

      log_msg "INFO" "Removed $APPLE_ARTIFACTS_REMOVED Apple artifact file(s)"

    fi

    rescan_mp4_files

  fi

}

remove_zero_size_mp4() {

  local file

  while IFS= read -r file; do

    [[ -n "$file" ]] || continue

    if [[ ! -s "$file" ]]; then

      ZERO_SIZE_REMOVED=$((ZERO_SIZE_REMOVED + 1))

      printf '%s\n' "$file" >> "$TMP_ZERO"

      vlog_msg "Zero-size MP4: $file"

      safe_remove_file "$file"

    fi

  done < "$TMP_MP4_LIST"

  if [[ "$ZERO_SIZE_REMOVED" -gt 0 ]]; then

    if [[ "$DRY_RUN" == true ]]; then

      log_msg "INFO" "Would remove $ZERO_SIZE_REMOVED zero-size MP4 file(s)"

    else

      log_msg "INFO" "Removed $ZERO_SIZE_REMOVED zero-size MP4 file(s)"

    fi

    rescan_mp4_files

  fi

}

collect_duplicate_actions() {

  local file base dir timestamp suffix

  : > "$TMP_ACTIONS"

  : > "$TMP_NONSTANDARD"

  while IFS= read -r file; do

    [[ -n "$file" ]] || continue

    base="$(basename "$file")"

    if [[ "$base" =~ ^([0-9]{4}-[0-9]{2}-[0-9]{2}_[0-9]{2}-[0-9]{2}-[0-9]{2})(_[0-9]+)?\.mp4$ ]]; then

      dir="$(dirname "$file")"

      timestamp="${BASH_REMATCH[1]}"

      suffix="${BASH_REMATCH[2]:-}"

      if [[ -n "$suffix" ]]; then

        suffix="${suffix#_}"

      else

        suffix=0

      fi

      printf '%s\t%s\t%s\t%s\n' "$dir" "$timestamp" "$suffix" "$file" >> "$TMP_ACTIONS"

    elif [[ "$base" =~ _[0-9]+\.mp4$ ]]; then

      printf '%s\n' "$file" >> "$TMP_NONSTANDARD"

      NONSTANDARD_REMOVED=$((NONSTANDARD_REMOVED + 1))

      vlog_msg "Non-standard duplicate-like file: $file"

      safe_remove_file "$file"

    fi

  done < "$TMP_MP4_LIST"

}

build_rename_plan() {

  awk -F'\t' '

function flush() {

  if (dup_count == 1 && orig_seen == 0) {

    print "RENAME\t" dup_files[1] "\t" dir "\t" timestamp

  } else if (dup_count > 0) {

    print "GROUP\t" dir "\t" timestamp "\t" dup_count

    for (i = 1; i <= dup_count; i++) {

      print "BLOCK\t" dup_files[i]

    }

  }

}

BEGIN {

  OFS = "\t"

  dir = ""

  timestamp = ""

  orig_seen = 0

  dup_count = 0

}

{

  if ($1 != dir || $2 != timestamp) {

    if (NR > 1) {

      flush()

    }

    dir = $1

    timestamp = $2

    orig_seen = 0

    dup_count = 0

    delete dup_files

  }

  if ($3 == 0) {

    orig_seen = 1

  } else {

    dup_count++

    dup_files[dup_count] = $4

  }

}

END {

  if (NR > 0) {

    flush()

  }

}

' "$TMP_ACTIONS" > "$TMP_ACTIONS.tmp"

  mv "$TMP_ACTIONS.tmp" "$TMP_ACTIONS"

}

apply_rename_plan() {

  local action src dir timestamp dup_count dst

  while IFS=$'\t' read -r action src dir timestamp dup_count; do

    [[ -n "$action" ]] || continue

    case "$action" in

      RENAME)

        dst="$dir/$timestamp.mp4"

        RENAMES_DONE=$((RENAMES_DONE + 1))

        if [[ "$DRY_RUN" == true ]]; then

          log_msg "INFO" "DRY-RUN rename: $src -> $dst"

        else

          mv -- "$src" "$dst"

          vlog_msg "Renamed: $src -> $dst"

        fi

        ;;

      GROUP)

        BLOCKED_GROUPS=$((BLOCKED_GROUPS + 1))

        ;;

      BLOCK)

        BLOCKED_FILES=$((BLOCKED_FILES + 1))

        printf '%s\n' "$src" >> "$TMP_BLOCKED"

        ;;

    esac

  done < "$TMP_ACTIONS"

}

print_summary_lists() {

  if [[ -s "$TMP_APPLE" ]]; then

    if [[ "$DRY_RUN" == true ]]; then

      log_msg "INFO" "Apple artifacts that would be removed:"

    else

      log_msg "INFO" "Apple artifacts removed:"

    fi

    cat "$TMP_APPLE"

  fi

  if [[ -s "$TMP_ZERO" ]]; then

    if [[ "$DRY_RUN" == true ]]; then

      log_msg "INFO" "Zero-size MP4 files that would be removed:"

    else

      log_msg "INFO" "Zero-size MP4 files removed:"

    fi

    cat "$TMP_ZERO"

  fi

  if [[ -s "$TMP_NONSTANDARD" ]]; then

    if [[ "$DRY_RUN" == true ]]; then

      log_msg "INFO" "Non-standard duplicate-like MP4 files that would be removed:"

    else

      log_msg "INFO" "Non-standard duplicate-like MP4 files removed:"

    fi

    cat "$TMP_NONSTANDARD"

  fi

  if [[ -s "$TMP_BLOCKED" ]]; then

    log_msg "WARN" "Blocked duplicate files (manual review needed):"

    cat "$TMP_BLOCKED"

  fi

}

print_summary() {

  local mode_text

  mode_text="apply"

  if [[ "$DRY_RUN" == true ]]; then

    mode_text="dry-run"

  fi

  log_msg "INFO" "Summary ($mode_text): apple_removed=$APPLE_ARTIFACTS_REMOVED zero_removed=$ZERO_SIZE_REMOVED nonstandard_removed=$NONSTANDARD_REMOVED renamed=$RENAMES_DONE blocked_groups=$BLOCKED_GROUPS blocked_files=$BLOCKED_FILES"

}

main() {

  parse_args "$@"

  init_tmp_files

  validate_media_root

  log_msg "INFO" "Starting cleanup for media root: $MEDIA_ROOT"

  if [[ "$DRY_RUN" == true ]]; then

    log_msg "INFO" "Dry-run enabled; no files will be changed"

  fi

  rescan_mp4_files

  remove_apple_artifacts

  remove_zero_size_mp4

  collect_duplicate_actions

  build_rename_plan

  apply_rename_plan

  print_summary_lists

  print_summary

  if [[ "$BLOCKED_GROUPS" -gt 0 ]]; then

    log_msg "WARN" "Cleanup completed with blocked duplicate groups"

    exit 1

  fi

  log_msg "INFO" "Cleanup completed successfully"

}

main "$@"