#!/bin/bash
set -e

# Build script for creating Debian package

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
PROJECT_DIR="$(dirname "$SCRIPT_DIR")"
BUILD_DIR="$PROJECT_DIR/build"
DEB_DIR="$PROJECT_DIR/debian"

# Colors for output
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
NC='\033[0m' # No Color

echo_info() {
    echo -e "${GREEN}[INFO]${NC} $1"
}

echo_warn() {
    echo -e "${YELLOW}[WARN]${NC} $1"
}

echo_error() {
    echo -e "${RED}[ERROR]${NC} $1"
}

# Clean previous builds
echo_info "Cleaning previous builds..."
rm -rf "$BUILD_DIR"
mkdir -p "$BUILD_DIR"

# Change to project directory
cd "$PROJECT_DIR"

# Build the applications
echo_info "Building SkyView applications..."
export CGO_ENABLED=0
export GOOS=linux
export GOARCH=amd64

VERSION=$(git describe --tags --always --dirty)
LDFLAGS="-w -s -X main.version=$VERSION"

# Build main skyview binary
echo_info "Building skyview..."
if ! go build -ldflags="$LDFLAGS" \
    -o "$DEB_DIR/usr/bin/skyview" \
    ./cmd/skyview; then
    echo_error "Failed to build skyview"
    exit 1
fi

# Build beast-dump utility
echo_info "Building beast-dump..."
if ! go build -ldflags="$LDFLAGS" \
    -o "$DEB_DIR/usr/bin/beast-dump" \
    ./cmd/beast-dump; then
    echo_error "Failed to build beast-dump"
    exit 1
fi

echo_info "Built binaries:"
echo_info "  skyview: $(file "$DEB_DIR/usr/bin/skyview")"
echo_info "  beast-dump: $(file "$DEB_DIR/usr/bin/beast-dump")"

# Set executable permissions
chmod +x "$DEB_DIR/usr/bin/skyview"
chmod +x "$DEB_DIR/usr/bin/beast-dump"

# Generate incremental changelog from git history
echo_info "Generating incremental changelog from git history..."
CHANGELOG_DIR="$DEB_DIR/usr/share/doc/skyview-adsb"
mkdir -p "$CHANGELOG_DIR"

# Function to generate incremental changelog
generate_incremental_changelog() {
    local changelog_file="$1"
    
    # Get all tags in reverse chronological order
    local tags
    tags=$(git tag -l --sort=-version:refname)
    
    # If no tags exist, create a single entry for current state
    if [ -z "$tags" ]; then
        local current_version
        current_version=$(git describe --tags --always)
        echo_info "No tags found, generating initial changelog for $current_version"
        {
            echo "skyview-adsb ($current_version) unstable; urgency=medium"
            echo ""
            echo "  * Initial release"
            echo "  * Multi-source ADS-B aircraft tracker with Beast format support"
            echo ""
            echo " -- $(git config user.name) <$(git config user.email)>  $(date -R)"
            echo ""
        } > "$changelog_file"
        return
    fi
    
    # Create empty changelog
    : > "$changelog_file"
    
    # Add entry for current development version if there are commits after the last tag
    local latest_tag
    latest_tag=$(echo "$tags" | head -n1)
    local commits_since_tag
    commits_since_tag=$(git rev-list "$latest_tag"..HEAD --count 2>/dev/null || echo 0)
    
    if [ "$commits_since_tag" -gt 0 ]; then
        local current_version
        current_version=$(git describe --tags --always)
        echo_info "Adding entry for current development version: $current_version"
        {
            echo "skyview-adsb ($current_version) unstable; urgency=medium"
            echo ""
            git log --pretty=format:"  * %s" "$latest_tag"..HEAD | head -20
            echo ""
            echo ""
            echo " -- $(git config user.name) <$(git config user.email)>  $(date -R)"
            echo ""
        } >> "$changelog_file"
    fi
    
    # Process all tags to create incremental changelog
    local prev_tag=""
    for tag in $tags; do
        echo_info "Processing version $tag"
        
        # Get tag date and author info
        local tag_date
        tag_date=$(git log -1 --format=%aD "$tag")
        local tag_author
        tag_author=$(git log -1 --format='%an <%ae>' "$tag")
        
        # Add version header
        {
            echo "skyview-adsb ($tag) unstable; urgency=medium"
            echo ""
        } >> "$changelog_file"
        
        # Add changes for this version
        if [ -n "$prev_tag" ]; then
            # Show changes between this tag and the previous one
            git log --pretty=format:"  * %s" "$tag..$prev_tag" | head -20 >> "$changelog_file"
        else
            # For the oldest tag, show changes from the beginning
            git log --pretty=format:"  * %s" "$tag" | head -20 >> "$changelog_file"
        fi
        
        # Add footer
        {
            echo ""
            echo ""
            echo " -- $tag_author  $tag_date"
            echo ""
        } >> "$changelog_file"
        
        prev_tag="$tag"
    done
}

# Generate the incremental changelog
generate_incremental_changelog "$CHANGELOG_DIR/changelog"
echo_info "Generated incremental changelog with $(grep -c '^skyview-adsb (' "$CHANGELOG_DIR/changelog") version entries"

# Compress changelog as per Debian standards (force overwrite if exists)
gzip -9f "$CHANGELOG_DIR/changelog"
echo_info "Generated changelog: $CHANGELOG_DIR/changelog.gz"

# Get package info
VERSION=$(grep "Version:" "$DEB_DIR/DEBIAN/control" | cut -d' ' -f2)
PACKAGE=$(grep "Package:" "$DEB_DIR/DEBIAN/control" | cut -d' ' -f2)
ARCH=$(grep "Architecture:" "$DEB_DIR/DEBIAN/control" | cut -d' ' -f2)

DEB_FILE="${PACKAGE}_${VERSION}_${ARCH}.deb"

echo_info "Creating Debian package: $DEB_FILE"

# Calculate installed size
INSTALLED_SIZE=$(du -sk "$DEB_DIR" | cut -f1)
sed -i "s/Installed-Size:.*/Installed-Size: $INSTALLED_SIZE/" "$DEB_DIR/DEBIAN/control" 2>/dev/null || \
    echo "Installed-Size: $INSTALLED_SIZE" >> "$DEB_DIR/DEBIAN/control"

# Build the package
if dpkg-deb --root-owner-group --build "$DEB_DIR" "$BUILD_DIR/$DEB_FILE"; then
    echo_info "Successfully created: $BUILD_DIR/$DEB_FILE"
    
    # Show package info
    echo_info "Package information:"
    dpkg-deb --info "$BUILD_DIR/$DEB_FILE"
    
    echo_info "Package contents:"
    dpkg-deb --contents "$BUILD_DIR/$DEB_FILE"
    
    # Test the package (requires root)
    if [ "$EUID" -eq 0 ]; then
        echo_info "Testing package installation (as root)..."
        dpkg --dry-run -i "$BUILD_DIR/$DEB_FILE"
    else
        echo_warn "Run as root to test package installation"
    fi
    
    echo_info "Debian package build complete!"
    echo_info "Install with: sudo dpkg -i $BUILD_DIR/$DEB_FILE"
    echo_info "Or upload to repository for apt installation"
else
    echo_error "Failed to create Debian package"
    exit 1
fi