import { NextRequest, NextResponse } from "next/server";
import { auth } from "@clerk/nextjs/server";
import { getDatabase } from "@/lib/database";
import log from "@/lib/logger";

// Helper to add CORS headers
function corsHeaders() {
  return {
    "Access-Control-Allow-Origin": "*",
    "Access-Control-Allow-Methods": "GET, POST, PUT, DELETE, OPTIONS",
    "Access-Control-Allow-Headers": "Content-Type, Authorization",
  };
}

// OPTIONS - Handle preflight requests
export async function OPTIONS() {
  return NextResponse.json({}, { headers: corsHeaders() });
}

// GET - Get specific goal
export async function GET(
  req: NextRequest,
  { params }: { params: Promise<{ id: string }> },
) {
  try {
    const { userId } = await auth();
    if (!userId) {
      return NextResponse.json(
        { error: "Unauthorized" },
        { status: 401, headers: corsHeaders() },
      );
    }

    const { id } = await params;
    const db = await getDatabase();

    const goal = await db.getFitnessGoalById(id);

    if (!goal) {
      return NextResponse.json(
        { error: "Goal not found" },
        { status: 404, headers: corsHeaders() },
      );
    }

    // Verify ownership
    if (goal.userId !== userId) {
      return NextResponse.json(
        { error: "Forbidden" },
        { status: 403, headers: corsHeaders() },
      );
    }

    return NextResponse.json(goal, { headers: corsHeaders() });
  } catch (error) {
    log.error("Failed to fetch fitness goal", error);
    return NextResponse.json(
      { error: "Internal server error" },
      { status: 500, headers: corsHeaders() },
    );
  }
}

// PUT - Update goal
export async function PUT(
  req: NextRequest,
  { params }: { params: Promise<{ id: string }> },
) {
  try {
    const { userId } = await auth();
    if (!userId) {
      return NextResponse.json(
        { error: "Unauthorized" },
        { status: 401, headers: corsHeaders() },
      );
    }

    const { id } = await params;
    const db = await getDatabase();

    // Verify goal exists and user owns it
    const existingGoal = await db.getFitnessGoalById(id);
    if (!existingGoal) {
      return NextResponse.json(
        { error: "Goal not found" },
        { status: 404, headers: corsHeaders() },
      );
    }
    if (existingGoal.userId !== userId) {
      return NextResponse.json(
        { error: "Forbidden" },
        { status: 403, headers: corsHeaders() },
      );
    }

    const updates = await req.json();

    // Don't allow changing userId or id
    delete updates.userId;
    delete updates.id;
    delete updates.createdAt;

    const updatedGoal = await db.updateFitnessGoal(id, updates);

    return NextResponse.json(updatedGoal, { headers: corsHeaders() });
  } catch (error) {
    log.error("Failed to update fitness goal", error);
    return NextResponse.json(
      { error: "Internal server error" },
      { status: 500, headers: corsHeaders() },
    );
  }
}

// DELETE - Delete goal
export async function DELETE(
  req: NextRequest,
  { params }: { params: Promise<{ id: string }> },
) {
  try {
    const { userId } = await auth();
    if (!userId) {
      return NextResponse.json(
        { error: "Unauthorized" },
        { status: 401, headers: corsHeaders() },
      );
    }

    const { id } = await params;
    const db = await getDatabase();

    // Verify goal exists and user owns it
    const existingGoal = await db.getFitnessGoalById(id);
    if (!existingGoal) {
      return NextResponse.json(
        { error: "Goal not found" },
        { status: 404, headers: corsHeaders() },
      );
    }
    if (existingGoal.userId !== userId) {
      return NextResponse.json(
        { error: "Forbidden" },
        { status: 403, headers: corsHeaders() },
      );
    }

    const deleted = await db.deleteFitnessGoal(id);

    if (deleted) {
      return NextResponse.json({ success: true }, { headers: corsHeaders() });
    } else {
      return NextResponse.json(
        { error: "Failed to delete goal" },
        { status: 500, headers: corsHeaders() },
      );
    }
  } catch (error) {
    log.error("Failed to delete fitness goal", error);
    return NextResponse.json(
      { error: "Internal server error" },
      { status: 500, headers: corsHeaders() },
    );
  }
}
