// clickup/create_task.ts
type TaskInput = {
  // REQUIRED FIELDS
  /** The ID of the list to put this task into */
  list_id: string;
  /** Name of the task (max 99840 chars) */
  name: string;

  // OPTIONAL CORE FIELDS  
  /** Detailed task description (supports markdown) */
  description?: string;
  /** Task status must match existing status in List */
  status?: string;
  /** Unix timestamp in milliseconds */
  due_date?: number;
  /** Unix timestamp in milliseconds */
  start_date?: number;
  /** Time estimate in milliseconds */
  time_estimate?: number;
  /** Markdown-formatted description */
  markdown_description?: string;
  /** Priority level (1-4) */
  priority?: 1 | 2 | 3 | 4;
  /** Parent task ID for subtasks */
  parent?: string;
  /** Custom task type ID */
  custom_item_id?: number;

  // PEOPLE MANAGEMENT  
  /** Array of user IDs */
  assignees?: number[];
  /** Notify all task members */
  notify_all?: boolean;

  // TAGS & RELATIONSHIPS
  /** Array of tag names */
  tags?: string[];
  /** Task dependencies */
  depends_on?: string[];
  /** Linked task IDs */
  links_to?: string;

  // CUSTOMIZATION
  /** Array of custom field objects */
  custom_fields?: {
    /** Custom field ID */
    id: string;
    /** Field value (type-specific) */
    value: string | number | boolean | string[];
  }[];

  // VALIDATION FLAGS
  /** Enforce required custom fields */
  check_required_custom_fields?: boolean;

  // ADVANCED OPTIONS
  /** Team ID for custom task IDs */
  team_id?: number;
  /** Custom task ID (requires team_id) */
  custom_task_id?: string;
  /** Task creation source (max 6 chars) */
  source?: string;
};

// All we need here is the access token.
type ClickupCredentials = {
  access_token: string;
};

export async function main(
  params: TaskInput,
  credentials: ClickupCredentials
) {
  // 1. Input Validation
  if (!params.list_id?.trim()) {
    throw new Error("Missing required field: list_id");
  }

  if (!params.name?.trim()) {
    throw new Error("Missing required field: name");
  }

  // 2. API Request Configuration
  const response = await fetch(`https://api.clickup.com/api/v2/list/${params.list_id}/task`, {
    method: "POST",
    headers: {
      "Content-Type": "application/json",
      "accept": 'application/json',
      "Authorization": "Bearer " + credentials.access_token
    },
    body: JSON.stringify({
      // Required
      name: params.name,

      // Core optional parameters
      description: params.description,
      status: params.status,
      due_date: params.due_date,
      start_date: params.start_date,
      time_estimate: params.time_estimate,
      markdown_description: params.markdown_description,
      priority: params.priority,
      parent: params.parent,
      custom_item_id: params.custom_item_id,

      // People management
      assignees: params.assignees,
      notify_all: params.notify_all,

      // Tags & relationships
      tags: params.tags,
      depends_on: params.depends_on,
      links_to: params.links_to,

      // Customization
      custom_fields: params.custom_fields?.map(field => ({
        id: field.id,
        value: field.value
      })),

      // Validation flags
      check_required_custom_fields: params.check_required_custom_fields,

      // Advanced configurations
      team_id: params.team_id,
      custom_task_id: params.custom_task_id,
      source: params.source
    })

  });

  // 3. Error Handling
  if (!response.ok) {
    const errorBody = await response.text();
    throw new Error(`ClickUp API Error (${response.status}): ${errorBody}`);
  }

  // 4. Response Processing
  const result = await response.json();

  // Validate successful task creation
  if (!result?.id) {
    throw new Error("Failed to create task: No ID returned");
  }

  return {
    task_id: result.id,
    url: result.url,
    status: result.status?.status || "created",
    _metadata: {
      clickup_space: result.space?.id,
      created_at: new Date().toISOString()
    }
  };
}