#!/bin/bash

# change-root.sh - Gentoo Chroot Entry Script
# Purpose: Set up bind mounts and enter Gentoo chroot environment
# Usage: Run after init.sh

# --- Colors for Output ---
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[0;33m'
NC='\033[0m'

# --- Configuration ---
GENTOO_ROOT="/mnt/gentoo"

set -e

echo -e "${YELLOW}Gentoo Chroot Setup Script${NC}"
echo -e "${YELLOW}=========================${NC}"

# --- Verify Gentoo root is mounted ---
if ! mountpoint -q "$GENTOO_ROOT" 2>/dev/null; then
    echo -e "${RED}Error: $GENTOO_ROOT is not mounted.${NC}"
    echo -e "${RED}Please run init.sh first to set up the Gentoo installation.${NC}"
    exit 1
fi

# --- Verify essential files exist ---
if [ ! -f "$GENTOO_ROOT/etc/portage/make.conf" ]; then
    echo -e "${YELLOW}Warning: $GENTOO_ROOT/etc/portage/make.conf not found.${NC}"
    echo -e "${YELLOW}init.sh should have copied this automatically.${NC}"
    read -r -p "Continue anyway? (y/n): " continue_confirm
    if [[ "$continue_confirm" != "y" ]]; then
        echo -e "${RED}Aborting. Please check init.sh output.${NC}"
        exit 1
    fi
fi

if [ ! -f "$GENTOO_ROOT/etc/resolv.conf" ]; then
    echo -e "${YELLOW}Copying resolv.conf...${NC}"
    if ! cp --dereference /etc/resolv.conf "$GENTOO_ROOT/etc/"; then
        echo -e "${RED}Error: Could not copy resolv.conf${NC}"
        exit 1
    fi
    echo -e "${GREEN}Copied resolv.conf${NC}"
fi

# --- Set up bind mounts ---
echo -e "${YELLOW}Setting up bind mounts for chroot environment...${NC}"

# Mount /proc
if ! mountpoint -q "$GENTOO_ROOT/proc" 2>/dev/null; then
    echo -e "${YELLOW}Mounting /proc...${NC}"
    mount --rbind /proc "$GENTOO_ROOT/proc"
    mount --make-rslave "$GENTOO_ROOT/proc"
    echo -e "${GREEN}Mounted /proc${NC}"
else
    echo -e "${YELLOW}/proc already mounted${NC}"
fi

# Mount /sys
if ! mountpoint -q "$GENTOO_ROOT/sys" 2>/dev/null; then
    echo -e "${YELLOW}Mounting /sys...${NC}"
    mount --rbind /sys "$GENTOO_ROOT/sys"
    mount --make-rslave "$GENTOO_ROOT/sys"
    echo -e "${GREEN}Mounted /sys${NC}"
else
    echo -e "${YELLOW}/sys already mounted${NC}"
fi

# Mount /dev
if ! mountpoint -q "$GENTOO_ROOT/dev" 2>/dev/null; then
    echo -e "${YELLOW}Mounting /dev...${NC}"
    mount --rbind /dev "$GENTOO_ROOT/dev"
    mount --make-rslave "$GENTOO_ROOT/dev"
    echo -e "${GREEN}Mounted /dev${NC}"
else
    echo -e "${YELLOW}/dev already mounted${NC}"
fi

# Mount /run
if ! mountpoint -q "$GENTOO_ROOT/run" 2>/dev/null; then
    echo -e "${YELLOW}Mounting /run...${NC}"
    mount --rbind /run "$GENTOO_ROOT/run"
    mount --make-rslave "$GENTOO_ROOT/run"
    echo -e "${GREEN}Mounted /run${NC}"
else
    echo -e "${YELLOW}/run already mounted${NC}"
fi

# --- Show mount status ---
echo -e "${GREEN}Bind mounts ready:${NC}"
echo "  /proc: $(mountpoint -q "$GENTOO_ROOT/proc" && echo "mounted" || echo "not mounted")"
echo "  /sys:  $(mountpoint -q "$GENTOO_ROOT/sys" && echo "mounted" || echo "not mounted")"
echo "  /dev:  $(mountpoint -q "$GENTOO_ROOT/dev" && echo "mounted" || echo "not mounted")"
echo "  /run:  $(mountpoint -q "$GENTOO_ROOT/run" && echo "mounted" || echo "not mounted")"

# --- Enter chroot ---
echo ""
echo -e "${GREEN}Entering Gentoo chroot environment...${NC}"
echo -e "${YELLOW}Type 'exit' when done to return to the live environment.${NC}"
echo ""

exec chroot "$GENTOO_ROOT" /bin/bash -c "source /etc/profile && export PS1='(chroot) \$PS1' && exec /bin/bash"