#!/usr/bin/env bash

# fzf_preview_mine

file="$1"

# cache for slow/big files, exr and hdr and ...
CACHE_DIR="${XDG_CACHE_HOME:-$HOME/.cache}/fzf_preview_mine"
mkdir -p "$CACHE_DIR"

# cache hash = hash + mtime
cache_key() {
    local f="$1"
    stat -c '%n-%Y' "$f" 2>/dev/null | md5sum | cut -d' ' -f1
}

# need command
need_cmd() {
    command -v "$1" >/dev/null 2>&1 || {
        echo "Error: missing dependency: $1" >&2
        return 1
    }
}

center() {
    local text="$1"
    local width="$FZF_PREVIEW_COLUMNS"
    local len=${#text}
    local pad=$(( (width - len) / 2 ))
    [[ $pad -lt 0 ]] && pad=0
    printf "%*s%s\n" "$pad" "" "$text"
}

# handle directories first
if [[ -d "$file" ]]; then
    center "[DIR] $file"
    # or better:
    tree -C -L 2 "$file"
    exit 0
fi

generic() {
    fold -s -w "$FZF_PREVIEW_COLUMNS" "$1" | head -n 2500
} 

# echo centered extension or filename (if there is no extension)
base="${file##*/}"
if [[ "$base" == *.* && "$base" != .* ]]; then
    ext="${base##*.}"
else
    ext="$base"
fi
center "$ext"


mime=$(file --mime-type -b "$file" 2>/dev/null)
encoding=$(file --mime-encoding -b "$file" 2>/dev/null)
debug="0"

tmp=$(mktemp -d)
cleanup() {
    pkill -P $$
    sleep 0.1
    rm -rf "$tmp"
}
trap cleanup EXIT


chafaView () {
    clear
    local file width_px height_px
    width_px="$((FZF_PREVIEW_COLUMNS))"
    height_px="$((FZF_PREVIEW_LINES))"
    file="$1"
    need_cmd chafa || exit 1
    chafa --dither=diffusion -f sixels -s "${width_px}x${height_px}" "$file" 2>/dev/null
    echo
}

if [[ $mime == image/* ]]; then
    (( debug )) && echo "image"

    if [[ "$file" == *.psd ]] || [[ "$file" = *.avif ]]; then
        need_cmd convert || exit 1
        convert "$file" -flatten "$tmp/tmp.png"
        file="$tmp/tmp.png"
    fi
    if [[ "$file" == *.svg ]]; then
        need_cmd inkscape || exit 1
        inkscape "$file" --actions="export-filename:$tmp/tmp.png; export-do" 2> /dev/null
        file="$tmp/tmp.png"
    fi

    # if [[ "$file" == *.exr ]] || [[ "$file" = *.hdr ]]; then
    #     #convert "$file" -colorspace sRGB -auto-gamma -auto-level "$tmp/tmp.png"
        
    #     # sudo apt install openimageio-tools  
    #     oiiotool "$file" --colorconvert linear sRGB -o "$tmp/tmp.png"
    #     file="$tmp/tmp.png"
    # fi

    # exr and hdr with cache
    if [[ "$file" == *.exr ]] || [[ "$file" == *.hdr ]]; then
        key=$(cache_key "$file")
        cached="$CACHE_DIR/${key}.png"

        if [[ -f "$cached" ]]; then
            file="$cached"
        else
            need_cmd oiiotool || exit 1
            oiiotool "$file" --resize 1200x0 --colorconvert linear sRGB -o "$cached" 2>/dev/null
            file="$cached"
        fi
    fi

    chafaView "$file" || generic "$file"

elif [[ $mime == audio/* ]] || [[ "${file,,}" == *.m4a ]] || [[ "${file,,}" == *.mp3 ]]; then
    need_cmd mediainfo || exit 1
    mediainfo "$file" 2> /dev/null
    need_cmd mpv || exit 1
    mpv --no-video --quiet "$file" 2> /dev/null

elif [[ $mime == video/* ]] || [[ "${file,,}" == *.mxf ]]; then
    (( debug )) && echo "video"
    dur=$(ffprobe -v panic -show_entries format=duration -of default=noprint_wrappers=1:nokey=1 "$file")
    [[ -z "$dur" || "$dur" == "N/A" ]] && dur=50
    halfdur=$(bc -l <<< "$dur / 2.00")

    need_cmd ffmpeg || exit 1
    ffmpeg -hide_banner -loglevel panic -ss "$halfdur" -i "$file" -frames:v 1 "$tmp/middle.png" -y

    chafaView "$tmp/middle.png"

elif [[ "$file" == *.blend ]] || [[ "$file" == *.blend1 ]]; then
    # need_cmd blender-thumbnailer || exit 1
    # blender-thumbnailer "$file" "$tmp/blend.png"
    # file="$tmp/blend.png"
    # chafaView "$file" || generic "$file"

    # need_cmd blender || exit 1

    blender="$HOME/blender_unpacked/blender-5.1.2-linux-x64/blender"

    if [[ ! -x "$blender" ]]; then
        blender="blender"
    fi
    
    info="$tmp/blend_info.txt"

    cat > "$tmp/blend_info.py" <<EOF
import bpy

scene = bpy.context.scene
cam_obj = scene.camera

with open(r"$info", "w") as f:

    # --- OBJECTS ---
    f.write("Objects:\n")

    for obj in sorted(bpy.data.objects, key=lambda o: o.type):
        f.write(f"{obj.type:<10} {obj.name}\n")

    # --- CAMERA ---
    f.write("\nCamera:\n")

    if cam_obj and cam_obj.data:
        cam = cam_obj.data

        cam_type_map = {
            'PERSP': 'Perspective',
            'ORTHO': 'Orthographic',
            'PANO': 'Panoramic'
        }

        f.write(f"Active camera: {cam_obj.name}\n")
        f.write(f"Type: {cam_type_map.get(cam.type, cam.type)}\n")
        f.write(f"Focal length: {cam.lens}mm\n")

        if cam.type == 'ORTHO':
            f.write(f"Ortho scale: {cam.ortho_scale}\n")

        dof = cam.dof
        f.write(f"DOF enabled: {dof.use_dof}\n")

        if dof.use_dof:
            f.write(f"Focus distance: {dof.focus_distance}\n")
            f.write(f"Aperture f-stop: {dof.aperture_fstop}\n")

    else:
        f.write("No active camera\n")
EOF
    $blender -b "$file" -P "$tmp/blend_info.py" >/dev/null 2>&1
    if [[ -f "$info" ]]; then
        cat "$info"
        echo
    else
        echo "No blend metadata"
        echo "or no blender found on path"
        echo "or blender is too old"
        echo
    fi
    
elif [[ "$file" == *.epub ]]; then
    {
        epub2txt -a -n "$file" 2>/dev/null ||
        pandoc "$file" -t plain 2>/dev/null
    } | fold -s -w "$FZF_PREVIEW_COLUMNS"

elif [[ "$file" == *.mobi ]]; then
    need_cmd ebook-convert || exit 1
    ebook-convert "$file" "$tmp/tmp.txt" 2>/dev/null
    clear
    fold -s -w "$FZF_PREVIEW_COLUMNS" "$tmp/tmp.txt"

elif [[ "$file" == *.html ]] || [[ "$file" == *.htm ]]; then
    need_cmd w3m || exit 1
    w3m -o display_link_number=1 -dump -cols "$FZF_PREVIEW_COLUMNS" "$file" || generic "$file"

elif [[ "$mime" == application/pdf ]]; then
    # graphical, show 1st page only
    need_cmd pdftocairo || exit 1
    pdftocairo -png -scale-to 1200 -singlefile "$file" "$tmp/out"
    chafaView "$tmp/out.png"  

    # textual, extract all text
    need_cmd pdftotext || exit 1
    pdftotext -layout "$file" - 2>/dev/null \
    | fold -s -w "$FZF_PREVIEW_COLUMNS"

    # use shift + up/down to switch between two previews

# atool for compressed stuff
elif [[ "$file" == *.zip || "$file" == *.tar || "$file" == *.tar.* || "$file" == *.7z || "$file" == *.rar || "$file" == *.gz || "$file" == *.bz2 || "$file" == *.xz ]]; then
    need_cmd als || exit 1
    als -l "$file" 2>/dev/null | head -n 500

elif [[ "$file" == *.deb ]]; then
    dpkg-deb --contents "$file"
    
elif [[ "$file" == *.docx ]]; then
    need_cmd pandoc || exit 1
    pandoc -s "$file" -t plain

# fonts
elif [[ "$file" == *.otf ]] || [[ "$file" == *.ttf ]] || [[ "$file" == *.woff ]]; then

    name="${file##*/}"      # fira.ttf
    name="${name%.*}"       # fira
    name="${name^^}"        # FIRA

    need_cmd convert || exit 1
    convert -size 1600x800 xc:black \
      -font "$file" \
      -fill white \
      -gravity northwest \
      \
      -pointsize 120 \
      -annotate +40+80 "${name}" \
      \
      -pointsize 60 \
      -annotate +40+320 "The quick brown čšž ČŠŽ\njumps over the lazy dog\n\nIN RHONCUS NULLA VEL ANTE,\nQUIS BLANDIT TURPIS SAGITTIS.\nSED SODALES, JUSTO AC PLACERAT." \
      \
      "$tmp/font.png"

    #open "$tmp/font.png"
    chafaView "$tmp/font.png"

elif [[ $encoding == binary ]]; then
    echo "[BINARY: $(basename "$file")]"
    need_cmd xxd || exit 1
    xxd "$file" | head -100 || strings "$file" | head -300

else

    generic "$file"

fi