#!/bin/bash

set -x

# Get yesterday's date
yesterday=$(date --date="yesterday" +%Y-%m-%d)
current_year=$(date +%Y)
day_of_year=$(date --date="$yesterday" +%j)  # Day of the year (1 to 366)

# Define base directory and music directory
base_dir="/home/motion/drives/local-2tb"
music_base_dir="/home/motion/drives/local-2tb/music/4 Seasons"

# Determine the season based on the day of the year
if [ "$day_of_year" -ge 80 ] && [ "$day_of_year" -le 172 ]; then
    season="Spring"
    season_start_date=80
    season_end_date=172
    days_in_season=92
elif [ "$day_of_year" -ge 173 ] && [ "$day_of_year" -le 264 ]; then
    season="Summer"
    season_start_date=173
    season_end_date=264
    days_in_season=92
elif [ "$day_of_year" -ge 265 ] && [ "$day_of_year" -le 355 ]; then
    season="Autumn"
    season_start_date=265
    season_end_date=355
    days_in_season=91
else
    season="Winter"
    season_start_date=356
    season_end_date=79
    days_in_season=90
fi

# Calculate the day of the season (from 1 to days_in_season)
if [ "$season" == "Winter" ]; then
    if [ "$day_of_year" -ge 355 ]; then
        # Winter season starts at day 1 on Dec 21st
        day_of_season=$(($day_of_year - 354))  # Day 1 of Winter starts on Dec 21st
    else
        # Before Dec 21st, Winter starts on Dec 21st in the previous year
        day_of_season=$((365 - 354 + $day_of_year))  # Adjust for the 365th day (Dec 20th) in the previous year
    fi
else
    day_of_season=$(($day_of_year - $season_start_date + 1))
fi

# Determine the movement based on the day of the season
if [ "$season" == "Winter" ]; then
    # Winter typically has three movements, so we calculate the movement number
    if [ "$day_of_season" -le 30 ]; then
        movement_num=1
    elif [ "$day_of_season" -le 60 ]; then
        movement_num=2
    else
        movement_num=3
    fi
else
    # Other seasons follow the same calculation for movement
    if [ "$day_of_season" -le 30 ]; then
        movement_num=1
    elif [ "$day_of_season" -le 60 ]; then
        movement_num=2
    else
        movement_num=3
    fi
fi

# Determine the music file based on the season and movement
music_file=$(find "$music_base_dir" -type f -iname "*$season Mvt $movement_num*" | head -n 1)

# Check if the music file exists
if [ ! -f "$music_file" ]; then
    echo "Music file for $season, Movement $movement_num not found!"
    exit 1
fi

# Get the duration of the music file in seconds
music_duration=$(ffprobe -v error -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 "$music_file")
echo "Music duration: $music_duration seconds"  # Printing the music duration for verification

# Define the directory where images are stored (using yesterday's date)
first_word_of_script_folder=$(basename "$(dirname "$(realpath "$0")")" | cut -d'-' -f1)
image_dir="$base_dir/$first_word_of_script_folder/$yesterday"

# Check if the image directory exists
if [ ! -d "$image_dir" ]; then
    echo "Error: Image directory $image_dir not found for $yesterday!"
    echo "Skipping this day's video generation."
    # Log the missing day
    echo "No images for $yesterday" >> /path/to/missing_days.log
    # Skip to the next day
    exit 0
fi

# Get today's date in yyyy-mm format for output directory
output_date=$(date +"%Y-%m")  # yyyy-mm format

# Dynamically generate the output directory based on season and movement
output_dir="$base_dir/movies/$first_word_of_script_folder/$season/Mvt$movement_num"
mkdir -p "$output_dir"

# Count the total number of images (JPEG files)
total_images=$(find "$image_dir" -type f -name "*.jpg" | wc -l)

# If there are no images, log it and move to the next day
if [ "$total_images" -lt 1 ]; then
    echo "Error: No images found in $image_dir for $yesterday."
    echo "Skipping this day's video generation."
    # Log the missing day
    echo "No images for $yesterday" >> /path/to/missing_days.log
    # Skip to the next day
    exit 0
fi

# Create a temporary text file with the sorted list of image paths
temp_file=$(mktemp)
find "$image_dir" -type f -name "*.jpg" | sort -n | while read image; do
  echo "file '$image'" >> "$temp_file"
done

# Calculate the number of images
num_images=$(wc -l < "$temp_file")
echo "Total images found for the video: $num_images"

# Calculate the target total duration (music duration + 3 seconds for transitions)
target_total_duration=$(echo "$music_duration + 3" | bc)
echo "Target total video duration (music + 3 seconds): $target_total_duration seconds"

# Calculate the target duration per video (based on number of days in the season)
target_duration_per_video=$(echo "$target_total_duration / $days_in_season" | bc -l)
echo "Each day's target video length: $target_duration_per_video seconds"

# Check if the daily video length is too short (less than 1.67 seconds)
if (( $(echo "$target_duration_per_video < 1.67" | bc -l) )); then
    echo "Daily video length is less than 1.67 seconds. Doubling the music duration."
    music_duration=$(echo "$music_duration * 2" | bc)
    target_total_duration=$(echo "$music_duration + 3" | bc)
    target_duration_per_video=$(echo "$target_total_duration / $days_in_season" | bc -l)
    echo "New target total video duration (after doubling music): $target_total_duration seconds"
    echo "New target duration per video: $target_duration_per_video seconds"
fi

# First, create the video using default frame rate (no speed-up or slow-down yet)
temp_video="$output_dir/${yesterday}_Mvt${movement_num}-temp.mp4"
echo "Creating video at default frame rate..."
ffmpeg -f concat -safe 0 -i "$temp_file" -c:v libx264 -pix_fmt yuv420p -crf 28 -vsync 2 -y "$temp_video"

# Check the duration of the created video
video_duration=$(ffmpeg -i "$temp_video" 2>&1 | grep "Duration" | cut -d ' ' -f 4 | sed s/,//)
echo "Initial video duration: $video_duration"

# Get the video duration in seconds (from HH:MM:SS format)
IFS=':' read -r hours minutes seconds <<< $(echo $video_duration | cut -d '.' -f1)  # Extract time
total_seconds=$(($hours * 3600 + $minutes * 60 + $seconds))  # Convert to total seconds

# Calculate the speed-up factor to make the video fit into the target duration
speed_up_factor=$(echo "scale=3; $total_seconds / $target_duration_per_video" | bc)
echo "Calculated speed-up factor: $speed_up_factor"

# Adjust the playback speed using the setpts filter to make the video fit into the target duration
final_file_name="${yesterday}_Mvt${movement_num}-Day${day_of_season}of${days_in_season}-final.mp4"
final_video="$output_dir/$final_file_name"
ffmpeg -i "$temp_video" -filter:v "setpts=PTS/$speed_up_factor" -y "$final_video"

# Check the duration of the adjusted video
adjusted_duration=$(ffmpeg -i "$final_video" 2>&1 | grep "Duration" | cut -d ' ' -f 4 | sed s/,//)
echo "Adjusted video duration: $adjusted_duration"

# Check for ffmpeg success
if [ $? -ne 0 ]; then
  echo "Error: ffmpeg failed to create the final video."
  exit 1
fi

# Inform user the video has been created
echo "Video created at $final_video"

# Clean up the temporary file
rm "$temp_file"