#!/bin/bash

APP_DIR="$HOME/.db-middleware"
CODE_DIR="$APP_DIR/code"
CONFIG_DIR="$APP_DIR/configs"
CONFIG_FILE="$CONFIG_DIR/app.conf"
REPO_URL="ssh://git@gitea.abdulha.de:222/IntegrateGlobals/db-middleware"

LOADED_CONFIG=0

# Default values
APP_NAME="Database Middleware"
IMAGE_NAME="db-middleware"
CONTAINER_NAME="con-db-middleware"

EXECUTION_MESSAGE="NO-RETURN"

print_header() {
    local HEADER_TEXT="$1"
    local MAX_LENGTH=0

    # Split the header text into lines and find the maximum line length
    while IFS= read -r LINE; do
        local LINE_LENGTH=${#LINE}
        if (( LINE_LENGTH > MAX_LENGTH )); then
            MAX_LENGTH=$LINE_LENGTH
        fi
    done <<< "$HEADER_TEXT"

    local BORDER_LENGTH=$((MAX_LENGTH + 2))  # Add 4 for padding (2 spaces)

    echo
    # Print the top border
    printf '+%*s+\n' "$BORDER_LENGTH" "" | tr ' ' '-'

    # Print each line of the header text
    while IFS= read -r LINE; do
        printf "| %-*s |\n" "$MAX_LENGTH" "$LINE"
    done <<< "$HEADER_TEXT"

    # Print the bottom border
    printf '+%*s+\n' "$BORDER_LENGTH" "" | tr ' ' '-'
    echo
}

build_docker_image() {
    if ! cd "$CODE_DIR"; then
        print_header "Failed to navigate to $CODE_DIR."
        return 1
    fi
    echo "Building Docker image..."
    
    # Check if BuildKit is installed
    if docker buildx version &>/dev/null; then
        echo "BuildKit detected. Enabling BuildKit..."
        export DOCKER_BUILDKIT=1
    else
        echo "BuildKit not found. Using legacy builder..."
        export DOCKER_BUILDKIT=0
    fi

    echo
    echo
    echo

    if docker build -t "$IMAGE_NAME" .; then
        echo "Docker image built successfully."
        return 0
    else
        echo "Failed to build Docker image."
        return 1
    fi
}

set_up_middleware() {
    print_header "Rebuilding the Docker Container..."

    if ! build_docker_image; then
        print_header "Can't build the Docker image."
        return 1  # Error
    fi

    if ! set_up_scripts; then
        print_header "Failed to set up scripts."
        return 1  # Error
    fi

    print_header "Rebuilt the Docker Container."
    return 0
}

test() {
    echo "I am here"
    return 1
}

exec_in_container() {
    # Returns 0 if the command was successful
    local CONTAINER_NAME=$CONTAINER_NAME
    local COMMAND="$1"

    # Check if the container is running
    if ! docker ps --format '{{.Names}}' | grep -q "^$CONTAINER_NAME$"; then
        print_header "Error: Container '$CONTAINER_NAME' is not running.

We can't execute commands inside it, you can run it with:

>>> $0 start"

        return 1
    fi

    # Execute the command in the container
    OUTPUT=$(docker exec "$CONTAINER_NAME" bash -c "$COMMAND" 2>&1)
    local EXIT_CODE=$?
    
    # Check if the command succeeded
    if [[ $EXIT_CODE -eq 0 ]]; then
        EXECUTION_MESSAGE="$OUTPUT"  # Return the output
        return 0
    else
        print_header "Error: Command failed in container '$CONTAINER_NAME' with exit code $EXIT_CODE.
Output: $OUTPUT"
        return $EXIT_CODE
    fi
}

set_up_scripts() {
    echo "Setting up scripts..."

    # Copy scripts
    if ! cp "$CODE_DIR/scripts/"* "$APP_DIR/scripts/"; then
        print_header "Failed to copy scripts."
        return 1
    fi

    # Give execution permission
    if ! chmod +x "$APP_DIR/scripts/"*; then
        print_header "Failed to set execution permissions."
        return 1
    fi

    # Create ~/.local/bin if it doesn't exist
    mkdir -p "$HOME/.local/bin"

    # Create symlink
    if ! ln -sf "$APP_DIR/scripts/manager.sh" "$HOME/.local/bin/db-middleware"; then
        print_header "Failed to create symlink."
        # TODO Here we should handle the case of having the symlink created previously.
        return 1
    fi

    # Update PATH
    if ! grep -q "$HOME/.local/bin" ~/.bashrc; then
        echo 'export PATH="$HOME/.local/bin:$PATH"' >> ~/.bashrc
    fi

    # Reload bashrc
    if ! source ~/.bashrc; then
        print_header "Failed to reload ~/.bashrc."
        return 1
    fi

    echo "Scripts set up successfully."
    return 0
}

create_user(){
    read -p "Enter username: " USERNAME
    read -p "Enter role (admin/user): " ROLE_INPUT
    local COMMAND="python3 -c 'from utils.scripts import create_user_script_sync;create_user_script_sync(username=\"$USERNAME\", role_input=\"$ROLE_INPUT\")'"
    exec_in_container "$COMMAND"
    local RETURN_CODE=$?

    if [[ $RETURN_CODE -eq 0 ]]; then
        print_header "$EXECUTION_MESSAGE"
    else
        print_header "Couldn't create the user due to the above error."
    fi
}

update_config() {
    print_header "Update configs."

    echo "Key: API_PORT, Current value: \`$API_PORT\`"
    echo "This is the internal port on your server's localhost network, where the Middleware will be listening to."
    read -p "  > Enter new value (leave empty to pass): " NEW_API_PORT
    echo    
    if [[ $NEW_API_PORT == "" ]]; then
        NEW_API_PORT=$API_PORT
    fi

    echo "Key: CONTAINER_NAME, Current value: \`$CONTAINER_NAME\`"
    echo "This is the name of the Docker Container we will create for this middleware."
    read -p "  > Enter new value (leave empty to pass): " NEW_CONTAINER_NAME
    echo
    if [[ $NEW_CONTAINER_NAME == "" ]]; then
        NEW_CONTAINER_NAME=$CONTAINER_NAME
    fi

    echo "Key: HAS_LOCAL_DBS, Current value: \`$HAS_LOCAL_DBS\`"
    echo "This will change the type of the network of the docker container, between a bridge or a host network."
    echo "Enter [0] if all your database are on another server(s)"
    echo "Enter [1] If you have a database on this server"
    read -p "  > Enter new value (leave empty to pass): " NEW_HAS_LOCAL_DBS
    echo
    if [[ $NEW_HAS_LOCAL_DBS == "" ]]; then
        NEW_HAS_LOCAL_DBS=$HAS_LOCAL_DBS
    fi

    print_header "Here are the old and new values:

API_PORT: \`$API_PORT > $NEW_API_PORT\`
CONTAINER_NAME: \`$CONTAINER_NAME > $NEW_CONTAINER_NAME\`
HAS_LOCAL_DBS: \`$HAS_LOCAL_DBS > $NEW_HAS_LOCAL_DBS\`"

    read -p "  > To confirm these changes, enter (y) otherwise enter anything: " CONFIRM_CHANGES

    if [[ $CONFIRM_CHANGES == "y" ]]; then
        
        API_PORT=$NEW_API_PORT
        CONTAINER_NAME=$NEW_CONTAINER_NAME
        HAS_LOCAL_DBS=$NEW_HAS_LOCAL_DBS

        write_config
        print_header "Saved the new configs! You can now rebuild the docker container."
        return 0
    fi

    print_header "Discarded the changes."
}

write_config() {
    CONFIG_TEXT="

# Application settings
APP_NAME=\"$APP_NAME\"
API_PORT=\"$API_PORT\"

# Docker Container settings
IMAGE_NAME=\"$IMAGE_NAME\"
CONTAINER_NAME=\"$CONTAINER_NAME\"

# Databases settings
HAS_LOCAL_DBS=\"$HAS_LOCAL_DBS\"

"
    echo "$CONFIG_TEXT" > "$CONFIG_FILE"
}

load_config() {
    if [[ -f "$CONFIG_FILE" ]]; then
        if source "$CONFIG_FILE"; then
            LOADED_CONFIG=1
            echo "Config file loaded successfully."
            return 0
        else
            print_header "Failed to load config file."
            return 1
        fi
    else
        print_header "Config file not found: $CONFIG_FILE"
        return 1
    fi
}

get_run_command() {
    local RUN_COMMAND="docker run -d --name $CONTAINER_NAME"
    if [[ $HAS_LOCAL_DBS -eq 1 || $HAS_LOCAL_DBS == "1" ]]; then
        RUN_COMMAND+=" --env API_HOST=localhost --env API_PORT=${API_PORT:-8080} --network host"
    else
        RUN_COMMAND+=" --env API_HOST=0.0.0.0 --env API_PORT=${API_PORT:-8080} -p ${API_PORT:-8080}:8080"
    fi
    RUN_COMMAND+=" -v /home/$USER/.db-middleware/files:/app/files $IMAGE_NAME"
    echo $RUN_COMMAND
}

show_config() {
    if [[ $LOADED_CONFIG -eq 0 ]]; then
        print_header "Config not loaded. Please load the config file first."
        return 1
    fi

    
    local RUN_COMMAND=$(get_run_command)

    print_header "Current Config:

CONTAINER_NAME: ${CONTAINER_NAME:-Not set}
API_PORT: ${API_PORT:-Not set}
HAS_LOCAL_DBS: ${HAS_LOCAL_DBS:-Not set}

Run Command: $RUN_COMMAND"

    return 0
}

convert_ports_to_docker_args() {
    local ports="$1"
    local docker_args=""

    if [[ -z "$ports" ]]; then
        echo "No ports provided."
        return 1
    fi

    # Split the ports by comma and trim whitespace
    IFS=',' read -r -a port_array <<< "$ports"

    # Loop through the ports and format them as Docker arguments
    for port in "${port_array[@]}"; do
        port=$(echo "$port" | xargs)  # Trim whitespace
        if [[ ! "$port" =~ ^[0-9]+$ ]]; then
            echo "Invalid port: $port"
            return 1
        fi
        docker_args+=" -p $port:$port"
    done

    echo "$docker_args"
    return 0
}

install() {
    print_header "Installing the Middleware..."

    if ! cd "$CODE_DIR"; then
        print_header "Failed to navigate to $CODE_DIR."
        return 1
    fi

    update_config

    print_header "Building the Docker Image..."

    if ! build_docker_image; then
        print_header "Failed to build Docker image."
        return 1
    fi
    
    print_header "Installed the Middleware Successfully!
- You can run the middleware simply using the manager:
  >>> db-middleware start

- Or directly by running the docker container:
  >>> $(get_run_command)"

    return 0
}

pull_clone_repo() {
    local UP_TO_DATE=-1  # Default: No changes

    echo "Setting up repository..."

    # Create directories if they don't exist
    mkdir -p "$APP_DIR/{code,configs,scripts}"

    # Navigate to the code directory
    if ! cd "$CODE_DIR"; then
        echo "Failed to navigate to $CODE_DIR."
        return 1  # Error
    fi

    # Check if the directory is empty
    if [[ -z "$(ls -A $CODE_DIR)" ]]; then
        echo "Directory is empty. Cloning repository..."
        if ! git clone "$REPO_URL" .; then
            echo "Failed to clone repository."
            return 1  # Error
        fi
        echo "Repository cloned successfully."
        UP_TO_DATE=0  # Changes were applied
    else
        # Check if the directory contains a Git repository
        if [[ -d ".git" ]]; then
            echo "Directory contains a Git repository."

            # Fetch the latest changes
            if ! git fetch origin; then
                echo "Failed to fetch changes from remote."
                return 1  # Error
            fi

            # Get the local and remote HEAD commit hashes
            echo
            LOCAL_HEAD=$(git rev-parse HEAD)
            REMOTE_HEAD=$(git rev-parse origin/main)
            exec_in_container "git rev-parse HEAD"
            local RETURN_CODE=$?
            CONTAINER_HEAD=$EXECUTION_MESSAGE
            EXECUTION_MESSAGE="NO-RETURN"
            echo
            echo "- Commit hash in remote origin: $REMOTE_HEAD"
            echo "- Commit hash in local repo: $LOCAL_HEAD"

            if [[ $RETURN_CODE -eq 0 ]]; then
                echo "- Commit hash in container: $CONTAINER_HEAD"
            else
                echo "Failed to get commit hash from container."
            fi


            echo
            if [[ "$CONTAINER_HEAD" == "$LOCAL_HEAD" && "$LOCAL_HEAD" == "$REMOTE_HEAD" ]]; then
                echo "Repo is up to date."
                UP_TO_DATE=-1
            elif [[ "$LOCAL_HEAD" != "$REMOTE_HEAD" ]]; then
                echo "Remote repository has new changes. Pulling latest changes..."
                echo
                if ! git pull "$REPO_URL"; then
                    echo "Failed to pull changes."
                    return 1  # Error
                fi
                echo
                echo "Local Repository updated successfully."
                LOCAL_HEAD=$(git rev-parse HEAD)
                UP_TO_DATE=0  # Changes were applied
            else
                echo "Local Repository is already up to date."
                UP_TO_DATE=-1  # No changes
                # echo $UP_TO_DATE
            fi

            if [[ "$LOCAL_HEAD" != "$CONTAINER_HEAD" ]]; then
                echo "Container Repository is not up to date."
                UP_TO_DATE=0
            fi

        else
            echo "Directory is not empty and does not contain a Git repository."
            echo "Please ensure the directory is empty or contains a valid Git repository."
            return 1  # Error
        fi
    fi

    echo "Repository setup completed successfully."

    return $UP_TO_DATE  # -1 = No changes, 0 = Changes applied
}

update_code() {
    print_header "Checking for updates..."
    

    pull_clone_repo
    local UP_TO_DATE=$?

    case $UP_TO_DATE in

     # 255 is -1, because Bash return codes are unsigned 8-bit integer, limited to the range 0 to 255. 
    -1|255)
        print_header "No changes detected."
        return -1  # No changes
        ;;
    0)
        print_header "Changes were detected and applied to local repo, but not to the container.
Need to rebuild the container, run:

  >>> db-middleware upgrade
"
        return 0  # Changes applied
        ;;
    1)
        print_header "Failed to update or clone repository."
        return 1  # Error
        ;;
    *)
        print_header "Wrong return code: \`$UP_TO_DATE\` from pull_clone_repo."
        return 1
        ;;
    esac
}

upgrade() {

    print_header "Upgrading the Middleware..."

    update_code
    local UPDATE_RESULT=$?

    case $UPDATE_RESULT in
        # 255 is -1, because Bash return codes are unsigned 8-bit integer, limited to the range 0 to 255. 
        -1|255)
            print_header "No changes detected. Skipping upgrade..."
            return -1
            ;;

        0)
        if ! set_up_middleware; then
            print_header "Failed to rebuild Docker image."
            return 1  # Error
        fi
            ;;

        1)
            print_header "Failed to update code. Upgrade aborted."
            return 1  # Error
            ;;
    esac

    print_header "Upgraded the Docker image.

We will stop & delete the current container and start a new one..."

    stop
    docker remove $CONTAINER_NAME
    start

    print_header "Upgraded the Middleware Successfully!"
    return 0
}


status() {
    print_header "Checking container status..."

    # Check if the container exists
    if ! docker ps -a --format '{{.Names}}' | grep -q "^$CONTAINER_NAME$"; then
        print_header "Container '$CONTAINER_NAME' does not exist."
        return 1
    fi

    # Get container status
    local CONTAINER_STATUS
    CONTAINER_STATUS=$(docker ps --filter "name=$CONTAINER_NAME" --format "{{.Status}}")

    if [[ -z "$CONTAINER_STATUS" ]]; then
        print_header "Container '$CONTAINER_NAME' is not running."
        return 0
    fi

    # Get detailed container information using `docker inspect`
    local CONTAINER_INFO
    CONTAINER_INFO=$(docker inspect "$CONTAINER_NAME" 2>/dev/null)

    if [[ -z "$CONTAINER_INFO" ]]; then
        print_header "Failed to inspect container '$CONTAINER_NAME'."
        return 1
    fi

    # Extract useful information
    local CPU_PERCENT MEM_USAGE MEM_PERCENT NET_IO BLOCK_IO IP_ADDRESS PORTS RUN_COMMAND NETWORK_MODE

    # Resource usage (CPU, memory, storage)
STATS_OUTPUT=$(docker stats --no-stream --format "{{.CPUPerc}}\t{{.MemUsage}}\t{{.MemPerc}}\t{{.NetIO}}\t{{.BlockIO}}" "$CONTAINER_NAME")

# Split the output into individual variables
IFS=$'\t' read -r CPU_PERCENT MEM_USAGE MEM_PERCENT NET_IO BLOCK_IO <<< "$STATS_OUTPUT"
    # Network information
    NETWORK_MODE=$(echo "$CONTAINER_INFO" | grep -oP '"NetworkMode": "\K[^"]+')
    if [[ "$NETWORK_MODE" == "host" ]]; then
        IP_ADDRESS="Host Network (No separate IP)"
        PORTS="Host Network (Ports are directly bound to host)"
    else
        IP_ADDRESS=$(echo "$CONTAINER_INFO" | grep -oP '"IPAddress": "\K[^"]+')
        
        # Extract port mappings from docker ps --no-trunc
        PORTS=$(docker ps --filter "name=$CONTAINER_NAME" --no-trunc --format "{{.Ports}}")
        if [[ -z "$PORTS" ]]; then
            PORTS="No port mappings"
        fi
    fi

    # Run command (from docker ps --no-trunc)
    RUN_COMMAND=$(docker ps --filter "name=$CONTAINER_NAME" --no-trunc --format "{{.Command}}")

    # Build the output string
    local OUTPUT
    OUTPUT="Database Middleware Status:


[Container]

  Name: $CONTAINER_NAME
  Status: $CONTAINER_STATUS

[Performance]

  CPU Usage: $CPU_PERCENT
  Memory Usage: $MEM_USAGE ($MEM_PERCENT)
  Block I/O: $BLOCK_IO
  Network I/O: $NET_IO

[Network]

  Network Mode: $NETWORK_MODE
  IP Address: $IP_ADDRESS
  Ports: $PORTS

[App]

  Run Command: $RUN_COMMAND"

    print_header "$OUTPUT"

    return 0
}

start() {
    RUN_COMMAND=$(get_run_command)

    print_header "Starting the Container...

With run command:
  >>> $RUN_COMMAND"

    # Check if a container with the same name already exists
    if docker ps -a --format '{{.Names}}' | grep -q "^$CONTAINER_NAME$"; then
        # Check if the container is already running
        if docker ps --format '{{.Names}}' | grep -q "^$CONTAINER_NAME$"; then
            print_header "Container '$CONTAINER_NAME' is already running.

You can restart it with:
  >>> $0 restart"
            return 0
        else
            # Start the existing container
            if docker start "$CONTAINER_NAME"; then
                print_header "Started the existing container '$CONTAINER_NAME' successfully."
                return 0
            else
                print_header "Failed to start the existing container '$CONTAINER_NAME'."
                return 1
            fi
        fi
    else
        # Run a new container
        if eval "$RUN_COMMAND"; then
            print_header "Started the container '$CONTAINER_NAME' successfully."
            return 0
        else
            print_header "Failed to start the container '$CONTAINER_NAME'."
            return 1
        fi
    fi
}

restart() {
    print_header "Restarting the Container..."

    # Check if a container with the same name exists (running or stopped)
    if docker ps -a --format '{{.Names}}' | grep -q "^$CONTAINER_NAME$"; then
        # Restart the container
        if docker restart "$CONTAINER_NAME"; then
            print_header "Restarted the container '$CONTAINER_NAME' successfully."
            return 0
        else
            print_header "Failed to restart the container '$CONTAINER_NAME'."
            return 1
        fi
    else
        print_header "Container '$CONTAINER_NAME' does not exist. Cannot restart.

You can start it with:
  >>> $0 start"
        return 1
    fi
}

stop() {
    print_header "Stopping the Container..."

    # Check if the container exists (running or stopped)
    if docker ps -a --format '{{.Names}}' | grep -q "^$CONTAINER_NAME$"; then
        # Check if the container is running
        if docker ps --format '{{.Names}}' | grep -q "^$CONTAINER_NAME$"; then
            # Stop the container
            if docker stop "$CONTAINER_NAME"; then
                print_header "Stopped the container '$CONTAINER_NAME' successfully."
                return 0
            else
                print_header "Failed to stop the container '$CONTAINER_NAME'."
                return 1
            fi
        else
            print_header "Container '$CONTAINER_NAME' is not running."
            return 0
        fi
    else
        print_header "Container '$CONTAINER_NAME' does not exist. Cannot stop."
        return 1
    fi
}

test_setup(){
    # Check if the container exists (running or stopped)
    if docker ps -a --format '{{.Names}}' | grep -q "^$CONTAINER_NAME$"; then
        # Check if the container is running
        if docker ps --format '{{.Names}}' | grep -q "^$CONTAINER_NAME$"; then
            # Stop the container
            RESPONSE=$(wget -qO- "http://127.0.0.1:$API_PORT/ping" 2>/dev/null)

            if [ "$RESPONSE" = '"Ok"' ]; then
                print_header "Container '$CONTAINER_NAME' is Found.
Container '$CONTAINER_NAME' is running.
App returned Ok to ping request."
                return 0
            else
                print_header "Container Found.
Container Running.
Error with the return of the App, it is not working right.
Response: $RESPONSE"
                return 1
            fi

        else
            print_header "Container '$CONTAINER_NAME' is Found.
Container '$CONTAINER_NAME' is not running."
            return 0
        fi
    else
        print_header "Container '$CONTAINER_NAME' does not exist."
        return 1
    fi
}

help() {
    print_header "help:

Source Code Management:
  > install
  > update_code
  > upgrade
  > rebuild

App Running:
  > status
  > test_setup
  > start
  > restart
  > stop

Users Management:
  > create_user

Configurations:
  > show_config
  > update_config

Help:
  > help
"
    exit 1
}


main() {
    # Check if an argument is provided
    if [[ $# -eq 0 ]]; then
        help
    fi
    
    if ! load_config; then
        print_header "Failed to load config. Exiting."
        exit 1
    fi
    # Handle the argument
    case "$1" in
        install) install ;;
        update_code) update_code ;;
        create_user) create_user ;;
        upgrade) upgrade ;;
        rebuild) set_up_middleware;;
        start) start ;;
        restart) restart;;
        status) status ;;
        stop) stop ;;
        show_config) show_config ;;
        update_config) update_config ;;
        test_setup) test_setup ;;
        help) help ;;
        *) echo "Invalid argument: $1"; help ;;
    esac
}

# Run the script with the provided arguments
main "$@"