/**
 * MCP Outline PostgreSQL - Attachments Tools
 * @author Descomplicar® | @link descomplicar.pt | @copyright 2026
 */

import { Pool } from 'pg';
import { BaseTool, ToolResponse, CreateAttachmentArgs, GetAttachmentArgs, PaginationArgs } from '../types/tools.js';
import { validatePagination, isValidUUID } from '../utils/security.js';

interface AttachmentListArgs extends PaginationArgs {
  document_id?: string;
  user_id?: string;
  team_id?: string;
}

/**
 * attachments.list - List attachments with optional filters
 */
const listAttachments: BaseTool<AttachmentListArgs> = {
  name: 'outline_attachments_list',
  description: 'List file attachments with optional filtering by document, user, or team. Supports pagination.',
  inputSchema: {
    type: 'object',
    properties: {
      document_id: {
        type: 'string',
        description: 'Filter by document ID (UUID)',
      },
      user_id: {
        type: 'string',
        description: 'Filter by user ID who uploaded (UUID)',
      },
      team_id: {
        type: 'string',
        description: 'Filter by team ID (UUID)',
      },
      limit: {
        type: 'number',
        description: 'Maximum number of results (default: 25, max: 100)',
      },
      offset: {
        type: 'number',
        description: 'Number of results to skip (default: 0)',
      },
    },
  },
  handler: async (args, pgClient): Promise<ToolResponse> => {
    const { limit, offset } = validatePagination(args.limit, args.offset);
    const conditions: string[] = [];
    const params: any[] = [];
    let paramIndex = 1;

    if (args.document_id) {
      if (!isValidUUID(args.document_id)) {
        throw new Error('Invalid document_id format');
      }
      conditions.push(`a."documentId" = $${paramIndex++}`);
      params.push(args.document_id);
    }

    if (args.user_id) {
      if (!isValidUUID(args.user_id)) {
        throw new Error('Invalid user_id format');
      }
      conditions.push(`a."userId" = $${paramIndex++}`);
      params.push(args.user_id);
    }

    if (args.team_id) {
      if (!isValidUUID(args.team_id)) {
        throw new Error('Invalid team_id format');
      }
      conditions.push(`a."teamId" = $${paramIndex++}`);
      params.push(args.team_id);
    }

    const whereClause = conditions.length > 0 ? `WHERE ${conditions.join(' AND ')}` : '';

    const query = `
      SELECT
        a.id,
        a.key,
        a."contentType",
        a.size,
        a.acl,
        a."documentId",
        a."userId",
        a."teamId",
        a."createdAt",
        a."updatedAt",
        a."lastAccessedAt",
        a."expiresAt",
        d.title as "documentTitle",
        u.name as "uploadedByName",
        u.email as "uploadedByEmail"
      FROM attachments a
      LEFT JOIN documents d ON a."documentId" = d.id
      LEFT JOIN users u ON a."userId" = u.id
      ${whereClause}
      ORDER BY a."createdAt" DESC
      LIMIT $${paramIndex++} OFFSET $${paramIndex}
    `;

    params.push(limit, offset);

    const result = await pgClient.query(query, params);

    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify(
            {
              data: result.rows,
              pagination: {
                limit,
                offset,
                total: result.rows.length,
              },
            },
            null,
            2
          ),
        },
      ],
    };
  },
};

/**
 * attachments.info - Get detailed information about a specific attachment
 */
const getAttachment: BaseTool<GetAttachmentArgs> = {
  name: 'outline_attachments_info',
  description: 'Get detailed information about a specific attachment by ID.',
  inputSchema: {
    type: 'object',
    properties: {
      id: {
        type: 'string',
        description: 'Attachment ID (UUID)',
      },
    },
    required: ['id'],
  },
  handler: async (args, pgClient): Promise<ToolResponse> => {
    if (!isValidUUID(args.id)) {
      throw new Error('Invalid attachment ID format');
    }

    const query = `
      SELECT
        a.id,
        a.key,
        a."contentType",
        a.size,
        a.acl,
        a."documentId",
        a."userId",
        a."teamId",
        a."createdAt",
        a."updatedAt",
        a."lastAccessedAt",
        a."expiresAt",
        d.title as "documentTitle",
        d."collectionId",
        u.name as "uploadedByName",
        u.email as "uploadedByEmail",
        t.name as "teamName"
      FROM attachments a
      LEFT JOIN documents d ON a."documentId" = d.id
      LEFT JOIN users u ON a."userId" = u.id
      LEFT JOIN teams t ON a."teamId" = t.id
      WHERE a.id = $1
    `;

    const result = await pgClient.query(query, [args.id]);

    if (result.rows.length === 0) {
      throw new Error('Attachment not found');
    }

    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify(
            {
              data: result.rows[0],
            },
            null,
            2
          ),
        },
      ],
    };
  },
};

/**
 * attachments.create - Create a new attachment record
 */
const createAttachment: BaseTool<CreateAttachmentArgs> = {
  name: 'outline_attachments_create',
  description: 'Create a new attachment record. Note: This creates the database record only, actual file upload is handled separately.',
  inputSchema: {
    type: 'object',
    properties: {
      name: {
        type: 'string',
        description: 'Attachment filename/key',
      },
      document_id: {
        type: 'string',
        description: 'Document ID to attach to (UUID, optional)',
      },
      content_type: {
        type: 'string',
        description: 'MIME type (e.g., "image/png", "application/pdf")',
      },
      size: {
        type: 'number',
        description: 'File size in bytes',
      },
    },
    required: ['name', 'content_type', 'size'],
  },
  handler: async (args, pgClient): Promise<ToolResponse> => {
    if (args.document_id && !isValidUUID(args.document_id)) {
      throw new Error('Invalid document_id format');
    }

    // Verify document exists if provided
    if (args.document_id) {
      const docCheck = await pgClient.query(
        'SELECT id, "teamId" FROM documents WHERE id = $1 AND "deletedAt" IS NULL',
        [args.document_id]
      );

      if (docCheck.rows.length === 0) {
        throw new Error('Document not found or deleted');
      }
    }

    // Get first admin user and team
    const userQuery = await pgClient.query(
      "SELECT u.id, u.\"teamId\" FROM users u WHERE u.role = 'admin' AND u.\"deletedAt\" IS NULL LIMIT 1"
    );

    if (userQuery.rows.length === 0) {
      throw new Error('No valid user found to create attachment');
    }

    const userId = userQuery.rows[0].id;
    const teamId = userQuery.rows[0].teamId;

    // Generate key (path in storage)
    const key = `attachments/${Date.now()}-${args.name}`;

    const query = `
      INSERT INTO attachments (
        id,
        key,
        "contentType",
        size,
        acl,
        "documentId",
        "userId",
        "teamId",
        "createdAt",
        "updatedAt"
      ) VALUES (gen_random_uuid(), $1, $2, $3, $4, $5, $6, $7, NOW(), NOW())
      RETURNING *
    `;

    const result = await pgClient.query(query, [
      key,
      args.content_type,
      args.size,
      'private', // Default ACL
      args.document_id || null,
      userId,
      teamId,
    ]);

    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify(
            {
              data: result.rows[0],
            },
            null,
            2
          ),
        },
      ],
    };
  },
};

/**
 * attachments.delete - Delete an attachment (soft delete)
 */
const deleteAttachment: BaseTool<GetAttachmentArgs> = {
  name: 'outline_attachments_delete',
  description: 'Delete an attachment permanently.',
  inputSchema: {
    type: 'object',
    properties: {
      id: {
        type: 'string',
        description: 'Attachment ID (UUID)',
      },
    },
    required: ['id'],
  },
  handler: async (args, pgClient): Promise<ToolResponse> => {
    if (!isValidUUID(args.id)) {
      throw new Error('Invalid attachment ID format');
    }

    const query = `
      DELETE FROM attachments
      WHERE id = $1
      RETURNING id, key, "documentId"
    `;

    const result = await pgClient.query(query, [args.id]);

    if (result.rows.length === 0) {
      throw new Error('Attachment not found');
    }

    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify(
            {
              success: true,
              message: 'Attachment deleted successfully',
              data: result.rows[0],
            },
            null,
            2
          ),
        },
      ],
    };
  },
};

/**
 * attachments.stats - Get attachment statistics
 */
const getAttachmentStats: BaseTool<{ team_id?: string; document_id?: string }> = {
  name: 'outline_attachments_stats',
  description: 'Get statistics about attachments including total count, size, and breakdown by content type.',
  inputSchema: {
    type: 'object',
    properties: {
      team_id: {
        type: 'string',
        description: 'Filter statistics by team ID (UUID)',
      },
      document_id: {
        type: 'string',
        description: 'Filter statistics by document ID (UUID)',
      },
    },
  },
  handler: async (args, pgClient): Promise<ToolResponse> => {
    const conditions: string[] = [];
    const params: any[] = [];
    let paramIndex = 1;

    if (args.team_id) {
      if (!isValidUUID(args.team_id)) {
        throw new Error('Invalid team_id format');
      }
      conditions.push(`a."teamId" = $${paramIndex++}`);
      params.push(args.team_id);
    }

    if (args.document_id) {
      if (!isValidUUID(args.document_id)) {
        throw new Error('Invalid document_id format');
      }
      conditions.push(`a."documentId" = $${paramIndex++}`);
      params.push(args.document_id);
    }

    const whereClause = conditions.length > 0 ? `WHERE ${conditions.join(' AND ')}` : '';

    // Overall statistics
    const overallStatsQuery = await pgClient.query(
      `SELECT
        COUNT(*) as "totalAttachments",
        SUM(size) as "totalSize",
        AVG(size) as "averageSize",
        COUNT(DISTINCT "documentId") as "documentsWithAttachments",
        COUNT(DISTINCT "userId") as "uniqueUploaders"
       FROM attachments a
       ${whereClause}`,
      params
    );

    // By content type
    const byContentTypeQuery = await pgClient.query(
      `SELECT
        a."contentType",
        COUNT(*) as count,
        SUM(size) as "totalSize"
       FROM attachments a
       ${whereClause}
       GROUP BY a."contentType"
       ORDER BY count DESC`,
      params
    );

    // Top uploaders
    const topUploadersQuery = await pgClient.query(
      `SELECT
        a."userId",
        u.name as "userName",
        u.email as "userEmail",
        COUNT(*) as "attachmentCount",
        SUM(a.size) as "totalSize"
       FROM attachments a
       LEFT JOIN users u ON a."userId" = u.id
       ${whereClause}
       GROUP BY a."userId", u.name, u.email
       ORDER BY "attachmentCount" DESC
       LIMIT 10`,
      params
    );

    // Recent uploads
    const recentUploadsQuery = await pgClient.query(
      `SELECT
        a.id,
        a.key,
        a."contentType",
        a.size,
        a."createdAt",
        u.name as "uploadedByName",
        d.title as "documentTitle"
       FROM attachments a
       LEFT JOIN users u ON a."userId" = u.id
       LEFT JOIN documents d ON a."documentId" = d.id
       ${whereClause}
       ORDER BY a."createdAt" DESC
       LIMIT 10`,
      params
    );

    return {
      content: [
        {
          type: 'text',
          text: JSON.stringify(
            {
              overall: overallStatsQuery.rows[0],
              byContentType: byContentTypeQuery.rows,
              topUploaders: topUploadersQuery.rows,
              recentUploads: recentUploadsQuery.rows,
            },
            null,
            2
          ),
        },
      ],
    };
  },
};

// Export all attachment tools
export const attachmentsTools: BaseTool<any>[] = [
  listAttachments,
  getAttachment,
  createAttachment,
  deleteAttachment,
  getAttachmentStats,
];