#!/bin/bash
set -euo pipefail

ARTIFACT_DIR="/opt/api-artifacts"
BUILDS_DIR="$ARTIFACT_DIR/builds"
SCRIPTS_DIR="$ARTIFACT_DIR/scripts"

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

log_info() { echo -e "${GREEN}[INFO]${NC} $1"; }
log_warn() { echo -e "${YELLOW}[WARN]${NC} $1"; }
log_error() { echo -e "${RED}[ERROR]${NC} $1"; }

if [ $# -ne 1 ]; then
    log_error "Usage: $0 <commit-hash>"
    exit 1
fi

COMMIT_HASH="$1"
BUILD_PATH="$BUILDS_DIR/$COMMIT_HASH"

if [ ! -d "$BUILD_PATH" ]; then
    log_error "Build not found: $BUILD_PATH"
    exit 1
fi

if [ ! -f "$BUILD_PATH/api-server" ]; then
    log_error "Binary not found in build: $BUILD_PATH/api-server"
    exit 1
fi

log_info "Starting deployment for commit: $COMMIT_HASH"

CURRENT_LINK="$ARTIFACT_DIR/current"
BLUE_LINK="$ARTIFACT_DIR/blue"
GREEN_LINK="$ARTIFACT_DIR/green"

if [ -L "$CURRENT_LINK" ]; then
    CURRENT_TARGET=$(readlink "$CURRENT_LINK")
    if [ "$CURRENT_TARGET" = "blue" ]; then
        TARGET_SLOT="green"
        INACTIVE_LINK="$GREEN_LINK"
    else
        TARGET_SLOT="blue"
        INACTIVE_LINK="$BLUE_LINK"
    fi
else
    TARGET_SLOT="blue"
    INACTIVE_LINK="$BLUE_LINK"
fi

log_info "Deploying to slot: $TARGET_SLOT"

ln -sfn "$BUILD_PATH" "$INACTIVE_LINK"

log_info "Symlink updated: $INACTIVE_LINK -> $BUILD_PATH"

log_info "Running database migrations..."
if ! "$SCRIPTS_DIR/migrate.sh" "$TARGET_SLOT"; then
    log_error "Migration failed, aborting deployment"
    exit 1
fi

log_info "Deployment staged to $TARGET_SLOT slot"
log_info "Build ready at: $BUILD_PATH"
log_info ""
log_info "To promote this deployment to production, run:"
log_info "  sudo $SCRIPTS_DIR/promote.sh"
log_info ""
log_info "To test before promoting:"
log_info "  Check $INACTIVE_LINK for manual verification"