#!/bin/sh

# Replace the local `dotfiles` repository with a fresh install
# by downloading and re-running the latest `install-dotfiles`
#
# Refuses to run if there are uncommitted or unpushed changes,
# unless called with `--force`

set -eu


XDG_DATA_HOME="${XDG_DATA_HOME:-$HOME/.local/share}"  # also set in ~/.config/shell/env

DOTFILES_DIR="$XDG_DATA_HOME/dotfiles"  # also set in ~/.config/shell/env

INSTALLER_URL="https://code.webartifex.de/alexander/dotfiles/raw/branch/main/.local/bin/install-dotfiles"


force=0
[ "${1:-}" = "--force" ] && force=1


_git() {
    git --git-dir="$DOTFILES_DIR" --work-tree="$HOME" "$@"
}


branch="main"


if [ -d "$DOTFILES_DIR" ]; then

    # Keep the machine on its current branch (e.g., "desktop")
    branch=$(_git symbolic-ref --short HEAD)

    if [ "$force" -ne 1 ]; then

        if [ -n "$(_git status --porcelain)" ]; then
            echo ""
            echo "There are uncommitted changes!" >&2
            echo "" >&2
            _git --no-pager diff HEAD --stat >&2
            echo "" >&2
            echo "=> Commit and push them, or re-run with --force" >&2
            echo ""
            exit 1
        fi

        if _git rev-parse --verify --quiet "origin/$branch" >/dev/null \
            && [ -n "$(_git log --oneline "origin/$branch..$branch")" ]; then
            echo ""
            echo "There are unpushed commits!" >&2
            echo "" >&2
            _git --no-pager log --oneline "origin/$branch..$branch" >&2
            echo "" >&2
            echo "=> Push them, or re-run with --force" >&2
            echo ""
            exit 1
        fi

    fi

fi


installer=$(mktemp)
trap 'rm -f "$installer"' EXIT


if command -v curl >/dev/null 2>&1; then
    curl -fsSL "$INSTALLER_URL" -o "$installer"
elif command -v wget >/dev/null 2>&1; then
    wget -q "$INSTALLER_URL" -O "$installer"
else
    echo ""
    echo "Neither curl nor wget are installed!" >&2
    echo "=> Install one of them" >&2
    echo ""
    exit 1
fi


DOTFILES_BRANCH="$branch" FORCE_INSTALL=1 sh "$installer"