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

# pacdiff-merge - Merge .pacnew files using pacdiff and meld (or $MERGE_TOOL)
MERGE_TOOL="${MERGE_TOOL:-/usr/bin/meld}"
REQUIRED_CMDS=(pacdiff sudo snapper "$MERGE_TOOL")

for cmd in "${REQUIRED_CMDS[@]}"; do
    command -v "${cmd%% *}" >/dev/null 2>&1 || { echo "Missing required command: $cmd"; exit 1; }
done

export SUDO_EDITOR="$MERGE_TOOL"
mapfile -t pacfiles < <(/usr/bin/pacdiff --output)
if [[ ${#pacfiles[@]} -eq 0 ]]; then
    echo "No .pacnew files found. Nothing to merge."
    if [[ -t 0 ]]; then
        read -rp "Press enter to finish."
    fi
    exit 0
fi

echo "Creating pre-merge snapshot..."
snap=$(sudo snapper create -d "Before PacDiff merge" -p)
echo "Created snapshot ${snap}"

for i in "${pacfiles[@]}"; do
    echo -e "\nMerging ${i} ..."
    /usr/bin/sudo -e "${i}" "${i/.pacnew/}"

    while true; do
        read -erp 'Were the files successfully merged? (delete .pacnew) [y/N/q] ' answer
        case "$answer" in
            [Yy]*) echo "Deleting ${i}..."; sudo rm "${i}"; break ;;
            [Qq]*) echo "Aborting."; exit 1 ;;
            [Nn]*|"") break ;;
            *) echo "Invalid input. Please enter 'y', 'n', or 'q'." ;;
        esac
    done

done

echo -e "\nAll .pacnew files processed."
read -rp "Press enter to finish."
