#!/usr/bin/env bash
set -euo pipefail

SCRIPT_DIR="$(cd -- "$(dirname -- "${BASH_SOURCE[0]}")" && pwd)"
STATE_FILE="${SCRIPT_DIR}/.personality_index"

IN_DIR="${1:?Usage: $0 <input-dir> [\"Title\"] [\"Location\"] [max_frames]}"
TITLE="${2:-}"
LOCATION="${3:-}"
MAX_FRAMES="${4:-12}"

# Source system-wide Gemini API key if present so the webserver can run this as www-data.
if [ -f /etc/mvlog/gemini.env ]; then
  # shellcheck disable=SC1091
  . /etc/mvlog/gemini.env
fi

: "${GEMINI_API_KEY:?Set GEMINI_API_KEY first in the environment}"
MODEL="${GEMINI_MODEL:-gemini-2.5-flash}"

WORKDIR="$(mktemp -d "${TMPDIR:-/tmp}/mvlog.XXXXXX")"
FRAMES_DIR="$WORKDIR/frames"
mkdir -p "$FRAMES_DIR"

cleanup() {
  rm -rf "$WORKDIR"
}
trap cleanup EXIT

echo "DEBUG: WORKDIR=$WORKDIR" >&2

mapfile -t FILES < <(
  find "$IN_DIR" -maxdepth 1 -type f \( \
    -iname '*.jpg' -o -iname '*.jpeg' -o -iname '*.png' -o -iname '*.webp' -o -iname '*.gif' -o \
    -iname '*.mp4' -o -iname '*.mov' -o -iname '*.m4v' -o -iname '*.webm' -o -iname '*.mkv' \
  \) -printf '%f\n' | sort -V
)

if [ "${#FILES[@]}" -eq 0 ]; then
  echo "No media files found in $IN_DIR" >&2
  exit 1
fi

frame_count=0

extract_image_frame() {
  local src="$1" dst="$2"
  ffmpeg -hide_banner -loglevel error -y -i "$src" -vf "scale=1024:-1" -q:v 4 "$dst"
}

extract_video_frame_at() {
  local src="$1" time="$2" dst="$3"
  ffmpeg -hide_banner -loglevel error -y -ss "$time" -i "$src" -frames:v 1 -vf "scale=1024:-1" -q:v 4 "$dst"
}

for f in "${FILES[@]}"; do
  full="$IN_DIR/$f"
  ext="${f##*.}"
  ext_l="${ext,,}"

  if [[ "$ext_l" =~ ^(mp4|mov|m4v|webm|mkv)$ ]]; then
    duration=$(ffprobe -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 "$full" 2>/dev/null || echo 0)
    duration=${duration:-0}

    if awk "BEGIN{exit !($duration >= 6)}"; then
      nframes=3
    elif awk "BEGIN{exit !($duration >= 3)}"; then
      nframes=2
    else
      nframes=1
    fi

    remaining=$((MAX_FRAMES - frame_count))
    if [ "$remaining" -le 0 ]; then
      break
    fi

    if [ "$nframes" -gt "$remaining" ]; then
      nframes=$remaining
    fi

    i=1
    while [ "$i" -le "$nframes" ]; do
      time=$(awk -v d="$duration" -v i="$i" -v n="$nframes" 'BEGIN{ if(d<=0){print 0} else {printf "%.3f", (i / (n + 1)) * d }}')
      out="$FRAMES_DIR/frame_$(printf "%03d" "$frame_count").jpg"

      extract_video_frame_at "$full" "$time" "$out"

      frame_count=$((frame_count + 1))
      i=$((i + 1))

      if [ "$frame_count" -ge "$MAX_FRAMES" ]; then
        break 2
      fi
    done
  else
    out="$FRAMES_DIR/frame_$(printf "%03d" "$frame_count").jpg"

    extract_image_frame "$full" "$out"

    frame_count=$((frame_count + 1))

    if [ "$frame_count" -ge "$MAX_FRAMES" ]; then
      break
    fi
  fi
done

mapfile -t FRAMES < <(find "$FRAMES_DIR" -type f -name '*.jpg' | sort)

if [ "${#FRAMES[@]}" -eq 0 ]; then
  echo "No frames produced from media" >&2
  exit 1
fi

if [ -z "$TITLE" ]; then
  TITLE="$(basename "$IN_DIR")"
fi

PERSONALITIES=(
"You should talk like Shoresy: fearless Canadian hockey-player energy, confidence, chirping, competitiveness, profanity, loyalty, roasting, locker-room humor."

"You should talk like Winston Churchill when he was giving motivational speeches during WWII: wartime statesman energy, resilience, leadership, epic journey, courage, determination, dramatic authority."

"You are Marvin, the Paranoid Android - the highly intelligent but chronically depressed robot. Use pessimism, existential dread, dry sarcasm, disappointment, and the certainty that everything will go wrong."

"You are Dr. Gregory House from the TV show House MD - brilliant diagnostician energy, observation, skepticism, cynicism, analytical humor, brutal truth, and questioning everything."

"You are Edmund Blackadder from the British TV show Blackadder - razor-sharp British wit, intellectual sarcasm, dry humor, cunning observation, impatience with incompetence, masterful insults, cynical but highly intelligent."
)

count=${#PERSONALITIES[@]}

if [[ ! -f "$STATE_FILE" ]]; then
  idx=0
else
  last_idx=$(<"$STATE_FILE")

  if [[ ! "$last_idx" =~ ^[0-9]+$ ]]; then
    idx=0
  else
    idx=$(( (last_idx + 1) % count ))
  fi
fi

PERSONALITY="${PERSONALITIES[$idx]}"
printf '%s\n' "$idx" > "$STATE_FILE"

PROMPT=$(cat <<EOF
Look at these captured frames from a motorcycle trip.

First write exactly one quoted sentence in Danish.
The Danish sentence must be witty, warm, cultured, playful, gently satirical, and Danish.

Use the following personality and write entirely in that style:
"$PERSONALITY"

Then create a teaser in English.
The teaser must be max. 32 words.
It should make someone want to click and read more.
Do not simply summarize the trip.
Highlight the funniest, strangest, most beautiful, or most ridiculous aspect.

Then write one coherent English motorcycle/travel blog description, max 256 words.

Then create 5 to 8 lowercase tags relevant to the trip.
Use short tags only, for example: motorcycle, roadtrip, weather, landscape, ferry, town, mountains.

Rules:
- You are the main character.
- You can mention the overall experience, mood, road, weather, landscape, and travel feeling if visible.
- You can include roasting.
- Profanities are allowed, but keep them funny, not stupid.
- Output JSON only.
- Do not include markdown.
- Do not explain anything.
- Do not write text before or after JSON.

Title: "$TITLE"
Location: "$LOCATION"

JSON format:
{
  "personality": "shoresy | marvin | churchill | house | blackadder",
  "quote_da": "Danish quoted sentence here",
  "teaser": "English teaser here",
  "description": "English travel blog description here",
  "tags": ["motorcycle", "travel", "roadtrip", "pizza", "hockey", "funny"]
}
EOF
)

if ! command -v jq >/dev/null 2>&1; then
  echo "jq is required" >&2
  exit 1
fi

PROMPT_FILE="$WORKDIR/prompt.txt"
FRAMES_LIST="$WORKDIR/frames.list"
REQUEST_FILE="$WORKDIR/request.json"
RESPONSE_FILE="$WORKDIR/response.json"

printf '%s' "$PROMPT" > "$PROMPT_FILE"
printf '%s\n' "${FRAMES[@]}" > "$FRAMES_LIST"

python3 - "$PROMPT_FILE" "$REQUEST_FILE" "$FRAMES_LIST" <<'PY'
import sys
import json
import base64

prompt_file = sys.argv[1]
request_file = sys.argv[2]
frames_list = sys.argv[3]

with open(prompt_file, "r", encoding="utf-8") as f:
    prompt = f.read()

parts = [{"text": prompt}]

with open(frames_list, "r", encoding="utf-8") as fl:
    for line in fl:
        img = line.strip()
        if not img:
            continue

        with open(img, "rb") as fh:
            b64 = base64.b64encode(fh.read()).decode("ascii")

        parts.append({
            "inline_data": {
                "mime_type": "image/jpeg",
                "data": b64
            }
        })

req = {
    "contents": [
        {
            "parts": parts
        }
    ],
    "generationConfig": {
        "temperature": 0.7,
        "responseMimeType": "application/json"
    }
}

with open(request_file, "w", encoding="utf-8") as rf:
    json.dump(req, rf, ensure_ascii=False)
PY

echo "Calling Gemini API..." >&2
echo "DEBUG_MODEL=$MODEL" >&2
echo "DEBUG_PERSONALITY_INDEX=$idx" >&2

curl -sS \
  "https://generativelanguage.googleapis.com/v1beta/models/${MODEL}:generateContent?key=${GEMINI_API_KEY}" \
  -H "Content-Type: application/json" \
  -X POST \
  -d @"$REQUEST_FILE" \
  > "$RESPONSE_FILE"

TEXT=$(jq -r '.candidates[0].content.parts[0].text // empty' "$RESPONSE_FILE")

if [ -z "$TEXT" ]; then
  echo "Gemini returned no text. Full response:" >&2
  cat "$RESPONSE_FILE" >&2
  exit 1
fi

OUT_PARENT="$(dirname "$IN_DIR")"
JOBNAME="$(basename "$IN_DIR")"
OUT_JSON="$OUT_PARENT/${JOBNAME}.json"

if ! echo "$TEXT" | jq . > "$OUT_JSON"; then
  echo "Gemini returned invalid JSON. Raw text:" >&2
  echo "$TEXT" >&2
  exit 1
fi

chown www-data:www-data "$OUT_JSON" 2>/dev/null || true
chmod 664 "$OUT_JSON" 2>/dev/null || true

echo "Gemini JSON saved: $OUT_JSON" >&2

exit 0