#!/bin/bash

# Gitea Backup and Update Script with Notifications

set -e

# Configuration
GITEA_HOME="/var/lib/gitea"
GITEA_USER="git"
GITEA_BIN="/usr/local/bin/gitea"
BACKUP_DIR="/var/backups/gitea"
LOG_FILE="/var/log/gitea-backup-update.log"

TIMESTAMP=$(date +"%Y%m%d_%H%M%S")
BACKUP_NAME="gitea_backup_${TIMESTAMP}"
HOSTNAME=$(hostname)

# Notification Settings

# Email notifications
ENABLE_EMAIL="false"
EMAIL_FROM="noreply@example.com"
EMAIL_TO="admin@example.com"

# Discord webhook
ENABLE_DISCORD="false"
DISCORD_WEBHOOK_URL="https://discordapp.com/api/webhooks/YOUR_WEBHOOK_ID/YOUR_WEBHOOK_TOKEN"

# Slack webhook
ENABLE_SLACK="false"
SLACK_WEBHOOK_URL="https://hooks.slack.com/services/YOUR/WEBHOOK/URL"

# Colors
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'

# Status tracking
STATUS="RUNNING"
STATUS_MESSAGE=""
START_TIME=$(date +%s)

# ------------------------------------------------------------
# Logging
# ------------------------------------------------------------

log() {
    echo "[$(date +'%Y-%m-%d %H:%M:%S')] $1" | tee -a "$LOG_FILE"
}

# ------------------------------------------------------------
# Notifications
# ------------------------------------------------------------

send_email() {
    local subject="$1"
    local body="$2"

    if [ "$ENABLE_EMAIL" != "true" ]; then
        return
    fi

    log "Sending email notification..."

    if command -v msmtp >/dev/null 2>&1; then
        {
            echo "To: $EMAIL_TO"
            echo "From: $EMAIL_FROM"
            echo "Subject: $subject"
            echo ""
            echo "$body"
        } | msmtp "$EMAIL_TO"

        log "${GREEN}Email sent successfully${NC}"
        return
    fi

    if command -v ssmtp >/dev/null 2>&1; then
        {
            echo "To: $EMAIL_TO"
            echo "From: $EMAIL_FROM"
            echo "Subject: $subject"
            echo ""
            echo "$body"
        } | ssmtp "$EMAIL_TO"

        log "${GREEN}Email sent successfully${NC}"
        return
    fi

    if command -v mail >/dev/null 2>&1; then
        echo "$body" | mail -s "$subject" "$EMAIL_TO"
        log "${GREEN}Email sent successfully${NC}"
        return
    fi

    log "${YELLOW}Warning: No mail client found${NC}"
}

send_discord() {
    if [ "$ENABLE_DISCORD" != "true" ] || [ -z "$DISCORD_WEBHOOK_URL" ]; then
        return
    fi

    local status_color
    local status_emoji

    case "$STATUS" in
        RUNNING)
            status_color="3447525"
            status_emoji="⏳"
            ;;
        SUCCESS)
            status_color="3066993"
            status_emoji="✅"
            ;;
        FAILED)
            status_color="15158332"
            status_emoji="❌"
            ;;
    esac

    local duration
    local duration_formatted

    duration=$(($(date +%s) - START_TIME))
    duration_formatted="$((duration / 60))m $((duration % 60))s"

    local payload
    payload=$(cat <<EOF
{
  "embeds": [{
    "title": "$status_emoji Gitea Backup & Update - $STATUS",
    "color": $status_color,
    "fields": [
      {
        "name": "Server",
        "value": "$HOSTNAME",
        "inline": true
      },
      {
        "name": "Duration",
        "value": "$duration_formatted",
        "inline": true
      },
      {
        "name": "Timestamp",
        "value": "$(date +'%Y-%m-%d %H:%M:%S')",
        "inline": false
      },
      {
        "name": "Status Message",
        "value": "${STATUS_MESSAGE:-Operation completed}",
        "inline": false
      },
      {
        "name": "Backup Location",
        "value": "$BACKUP_DIR",
        "inline": false
      }
    ],
    "footer": {
      "text": "Gitea Automation"
    }
  }]
}
EOF
)

    curl --silent --show-error \
        --request POST "$DISCORD_WEBHOOK_URL" \
        --header "Content-Type: application/json" \
        --data "$payload" \
        >/dev/null 2>&1 \
        || log "${YELLOW}Warning: Discord notification failed${NC}"
}

send_slack() {
    if [ "$ENABLE_SLACK" != "true" ] || [ -z "$SLACK_WEBHOOK_URL" ]; then
        return
    fi

    local status_color
    local status_emoji

    case "$STATUS" in
        RUNNING)
            status_color="warning"
            status_emoji="⏳"
            ;;
        SUCCESS)
            status_color="good"
            status_emoji="✅"
            ;;
        FAILED)
            status_color="danger"
            status_emoji="❌"
            ;;
    esac

    local duration
    local duration_formatted

    duration=$(($(date +%s) - START_TIME))
    duration_formatted="$((duration / 60))m $((duration % 60))s"

    local payload
    payload=$(cat <<EOF
{
  "attachments": [{
    "color": "$status_color",
    "title": "$status_emoji Gitea Backup & Update - $STATUS",
    "fields": [
      {
        "title": "Server",
        "value": "$HOSTNAME",
        "short": true
      },
      {
        "title": "Duration",
        "value": "$duration_formatted",
        "short": true
      },
      {
        "title": "Timestamp",
        "value": "$(date +'%Y-%m-%d %H:%M:%S')",
        "short": false
      },
      {
        "title": "Status Message",
        "value": "${STATUS_MESSAGE:-Operation completed}",
        "short": false
      },
      {
        "title": "Backup Location",
        "value": "$BACKUP_DIR",
        "short": false
      }
    ]
  }]
}
EOF
)

    curl --silent --show-error \
        --request POST "$SLACK_WEBHOOK_URL" \
        --header "Content-Type: application/json" \
        --data "$payload" \
        >/dev/null 2>&1 \
        || log "${YELLOW}Warning: Slack notification failed${NC}"
}

send_notifications() {
    log "Sending notifications..."

    local subject
    local body

    subject="Gitea Backup & Update - $STATUS"

    body="Gitea Backup and Update Script Results

Server: $HOSTNAME
Status: $STATUS
Duration: $(($(date +%s) - START_TIME)) seconds
Timestamp: $(date +'%Y-%m-%d %H:%M:%S')
Log File: $LOG_FILE

Details:
$STATUS_MESSAGE

Backup Location: $BACKUP_DIR"

    send_email "$subject" "$body"
    send_discord
    send_slack
}

error_exit() {
    log "${RED}ERROR: $1${NC}"

    STATUS="FAILED"
    STATUS_MESSAGE="$1"

    send_notifications
    exit 1
}

# ------------------------------------------------------------
# Initial checks
# ------------------------------------------------------------

if [[ $EUID -ne 0 ]]; then
    STATUS="FAILED"
    STATUS_MESSAGE="This script must be run as root"
    echo "$STATUS_MESSAGE"
    exit 1
fi

if [ ! -x "$GITEA_BIN" ]; then
    error_exit "Gitea binary not found or is not executable: $GITEA_BIN"
fi

if ! command -v curl >/dev/null 2>&1; then
    error_exit "curl is required but was not found"
fi

mkdir -p "$(dirname "$LOG_FILE")"

log "${GREEN}=== Gitea Backup and Update Started ===${NC}"

STATUS="RUNNING"
send_discord

# ------------------------------------------------------------
# Check installed and latest versions
# ------------------------------------------------------------

log "Checking installed Gitea version..."

INSTALLED_VERSION=$(
    "$GITEA_BIN" --version 2>/dev/null |
        grep -oE 'version [0-9]+\.[0-9]+\.[0-9]+' |
        awk '{print $2}' |
        head -n 1
)

if [ -z "$INSTALLED_VERSION" ]; then
    error_exit "Could not determine installed Gitea version"
fi

log "Checking latest Gitea release..."

LATEST_VERSION=$(
    curl --fail --silent --show-error \
        https://api.github.com/repos/go-gitea/gitea/releases/latest |
        grep -oP '"tag_name":\s*"\K[^"]+' |
        head -n 1
)

if [ -z "$LATEST_VERSION" ]; then
    error_exit "Failed to fetch latest Gitea version"
fi

LATEST_VERSION_NUMBER="${LATEST_VERSION#v}"

log "Installed version: $INSTALLED_VERSION"
log "Latest version:    $LATEST_VERSION_NUMBER"

# Exit before stopping Gitea or creating a backup if already current
if [ "$INSTALLED_VERSION" = "$LATEST_VERSION_NUMBER" ]; then
    STATUS="SUCCESS"
    STATUS_MESSAGE="Gitea is already up to date at version $INSTALLED_VERSION"

    log "${GREEN}$STATUS_MESSAGE${NC}"
    send_notifications
    exit 0
fi

log "${YELLOW}Update available: $INSTALLED_VERSION -> $LATEST_VERSION_NUMBER${NC}"

STATUS_MESSAGE="Update available: $INSTALLED_VERSION -> $LATEST_VERSION_NUMBER"
send_discord

# ------------------------------------------------------------
# Determine architecture
# ------------------------------------------------------------

ARCH=$(uname -m)

case "$ARCH" in
    x86_64)
        DOWNLOAD_ARCH="amd64"
        ;;
    aarch64)
        DOWNLOAD_ARCH="arm64"
        ;;
    armv7l)
        DOWNLOAD_ARCH="armv7"
        ;;
    *)
        error_exit "Unsupported architecture: $ARCH"
        ;;
esac

DOWNLOAD_URL="https://github.com/go-gitea/gitea/releases/download/${LATEST_VERSION}/gitea-${LATEST_VERSION_NUMBER}-linux-${DOWNLOAD_ARCH}"

# ------------------------------------------------------------
# Stop Gitea
# ------------------------------------------------------------

log "Stopping Gitea service..."

systemctl stop gitea ||
    error_exit "Failed to stop Gitea service"

sleep 2

# ------------------------------------------------------------
# Create backup
# ------------------------------------------------------------

log "Creating backup of Gitea data..."

mkdir -p "$BACKUP_DIR/$BACKUP_NAME"

cp -r "$GITEA_HOME" "$BACKUP_DIR/$BACKUP_NAME/gitea_home" ||
    error_exit "Failed to backup Gitea home directory"

cp "$GITEA_BIN" "$BACKUP_DIR/$BACKUP_NAME/gitea_bin_backup" ||
    error_exit "Failed to backup Gitea binary"

log "${GREEN}Backup created at: $BACKUP_DIR/$BACKUP_NAME${NC}"

STATUS_MESSAGE="Backup created successfully"
send_discord

# ------------------------------------------------------------
# Compress backup
# ------------------------------------------------------------

log "Compressing backup..."

cd "$BACKUP_DIR"

tar -czf "${BACKUP_NAME}.tar.gz" "$BACKUP_NAME" ||
    error_exit "Failed to compress backup"

rm -rf "$BACKUP_DIR/$BACKUP_NAME"

log "${GREEN}Backup compressed: $BACKUP_DIR/${BACKUP_NAME}.tar.gz${NC}"

# ------------------------------------------------------------
# Download and install Gitea
# ------------------------------------------------------------

log "Downloading Gitea $LATEST_VERSION_NUMBER..."
log "Download URL: $DOWNLOAD_URL"

TMP_BINARY=$(mktemp /tmp/gitea_new.XXXXXX)

curl --fail --location --silent --show-error \
    --output "$TMP_BINARY" \
    "$DOWNLOAD_URL" || {
        rm -f "$TMP_BINARY"
        error_exit "Failed to download Gitea"
    }

if [ ! -s "$TMP_BINARY" ]; then
    rm -f "$TMP_BINARY"
    error_exit "Downloaded Gitea binary is empty"
fi

log "Installing new Gitea binary..."

chmod 755 "$TMP_BINARY"
chown "$GITEA_USER:$GITEA_USER" "$TMP_BINARY"

mv "$TMP_BINARY" "$GITEA_BIN" ||
    error_exit "Failed to install new Gitea binary"

log "${GREEN}Gitea binary updated to $LATEST_VERSION_NUMBER${NC}"

STATUS_MESSAGE="Gitea updated from $INSTALLED_VERSION to $LATEST_VERSION_NUMBER"
send_discord

# ------------------------------------------------------------
# Start and verify Gitea
# ------------------------------------------------------------

log "Starting Gitea service..."

systemctl start gitea ||
    error_exit "Failed to start Gitea service"

sleep 3

if systemctl is-active --quiet gitea; then
    log "${GREEN}Gitea service is running${NC}"
else
    error_exit "Gitea service failed to start. Check the service logs."
fi

# ------------------------------------------------------------
# Clean up old backups
# ------------------------------------------------------------

log "Cleaning up old backups; keeping the last five..."

cd "$BACKUP_DIR"

ls -t *.tar.gz 2>/dev/null |
    tail -n +6 |
    xargs -r rm --

log "${GREEN}Backup cleanup completed${NC}"

# ------------------------------------------------------------
# Finish
# ------------------------------------------------------------

log "${GREEN}=== Gitea Backup and Update Completed Successfully ===${NC}"

STATUS="SUCCESS"
STATUS_MESSAGE="Backup completed and Gitea updated from $INSTALLED_VERSION to $LATEST_VERSION_NUMBER successfully"

send_notifications