#!/bin/bash

# big-latex-blob.sh — concatenate \input files from a LaTeX master into a single blob

if [ $# -ne 1 ]; then
    echo "Usage: $0 <master.tex>" >&2
    exit 1
fi

MASTER="$1"

if [ ! -f "$MASTER" ]; then
    echo "Error: '$MASTER' not found." >&2
    exit 1
fi

# Derive output filename: Longing.tex -> Longing-Blob.tex
BASENAME="${MASTER%.tex}"
OUTPUT="${BASENAME}-Blob.tex"

# Check that at least one \input line exists
if ! grep -q '\\input' "$MASTER"; then
    echo "Error: no \\input lines found in '$MASTER'." >&2
    exit 1
fi

grep '\\input' "$MASTER" | \
    sed 's/.*\\input{\(.*\)}/\1/' | \
    xargs -I{} sh -c '
        if [ ! -f "$1" ]; then
            echo "Warning: input file not found: $1" >&2
        else
            printf "\n%% --- %s ---\n\n" "$1"
            cat "$1"
        fi
    ' _ {} > "$OUTPUT"

echo "Written to: $OUTPUT"