import { Request, Response } from 'express';
import { AuthenticatedRequest } from '../middleware/auth.middleware';
import * as projectService from '../services/project.service';
import { CreateProjectInput, UpdateProjectInput, ProjectStatusType } from '../validators/project.validator';

/**
 * GET /projects
 * List all projects with pagination and optional filtering
 * Query params: page, pageSize, status, area_name, search
 */
export async function getAll(req: Request, res: Response): Promise<void> {
  try {
    const page = parseInt(req.query.page as string, 10) || 1;
    const pageSize = Math.min(parseInt(req.query.pageSize as string, 10) || 10, 100);

    const filters: projectService.ProjectFilters = {};

    if (req.query.status) {
      filters.status = req.query.status as ProjectStatusType;
    }

    if (req.query.area_name) {
      filters.area_name = req.query.area_name as string;
    }

    if (req.query.search) {
      filters.search = req.query.search as string;
    }

    const result = await projectService.getAll(filters, { page, pageSize });

    res.status(200).json({
      success: true,
      data: result.data,
      pagination: result.pagination,
    });
  } catch (error) {
    console.error('Error fetching projects:', error);
    res.status(500).json({
      success: false,
      error: 'Failed to fetch projects',
    });
  }
}

/**
 * GET /projects/:id
 * Get a single project by ID
 */
export async function getById(req: Request, res: Response): Promise<void> {
  try {
    const { id } = req.params;

    const project = await projectService.getById(id);

    if (!project) {
      res.status(404).json({
        success: false,
        error: 'Project not found',
      });
      return;
    }

    res.status(200).json({
      success: true,
      data: project,
    });
  } catch (error) {
    console.error('Error fetching project:', error);
    res.status(500).json({
      success: false,
      error: 'Failed to fetch project',
    });
  }
}

/**
 * POST /projects
 * Create a new project
 * Requires authentication
 */
export async function create(req: AuthenticatedRequest, res: Response): Promise<void> {
  try {
    const userId = req.user?.id;

    if (!userId) {
      res.status(401).json({
        success: false,
        error: 'Authentication required',
      });
      return;
    }

    const data = req.body as CreateProjectInput;

    const project = await projectService.create(data, userId);

    res.status(201).json({
      success: true,
      data: project,
    });
  } catch (error) {
    console.error('Error creating project:', error);
    res.status(500).json({
      success: false,
      error: 'Failed to create project',
    });
  }
}

/**
 * PUT /projects/:id
 * Update an existing project
 * Requires authentication
 */
export async function update(req: AuthenticatedRequest, res: Response): Promise<void> {
  try {
    const { id } = req.params;
    const data = req.body as UpdateProjectInput;

    const project = await projectService.update(id, data);

    if (!project) {
      res.status(404).json({
        success: false,
        error: 'Project not found',
      });
      return;
    }

    res.status(200).json({
      success: true,
      data: project,
    });
  } catch (error) {
    console.error('Error updating project:', error);
    res.status(500).json({
      success: false,
      error: 'Failed to update project',
    });
  }
}

/**
 * DELETE /projects/:id
 * Delete a project
 * Requires admin role
 */
export async function deleteProject(req: AuthenticatedRequest, res: Response): Promise<void> {
  try {
    const { id } = req.params;

    // First check if project exists
    const project = await projectService.getById(id);

    if (!project) {
      res.status(404).json({
        success: false,
        error: 'Project not found',
      });
      return;
    }

    const deleted = await projectService.deleteProject(id);

    if (!deleted) {
      res.status(500).json({
        success: false,
        error: 'Failed to delete project',
      });
      return;
    }

    res.status(200).json({
      success: true,
      data: { message: 'Project deleted successfully' },
    });
  } catch (error) {
    const message = error instanceof Error ? error.message : 'Failed to delete project';

    // Handle dependency error
    if (message.includes('Cannot delete project')) {
      res.status(409).json({
        success: false,
        error: message,
      });
      return;
    }

    console.error('Error deleting project:', error);
    res.status(500).json({
      success: false,
      error: 'Failed to delete project',
    });
  }
}

/**
 * GET /projects/:id/stats
 * Get project statistics
 */
export async function getStats(req: Request, res: Response): Promise<void> {
  try {
    const { id } = req.params;

    const stats = await projectService.getStats(id);

    if (!stats) {
      res.status(404).json({
        success: false,
        error: 'Project not found',
      });
      return;
    }

    res.status(200).json({
      success: true,
      data: stats,
    });
  } catch (error) {
    console.error('Error fetching project stats:', error);
    res.status(500).json({
      success: false,
      error: 'Failed to fetch project statistics',
    });
  }
}