/**
 * Template utility functions.
 *
 * Pure functions for parsing and formatting template data.
 * These functions have no React dependencies and can be used
 * in both TUI and CLI contexts.
 */

import type { XOTemplate, XOTemplateAction } from "@xo-cash/types";

/**
 * Formatted template list item data.
 */
export interface FormattedTemplateItem {
  /** The display label for the template */
  label: string;
  /** The template description */
  description?: string;
  /** Whether the template data is valid */
  isValid: boolean;
}

/**
 * Formatted action list item data.
 */
export interface FormattedActionItem {
  /** The display label for the action */
  label: string;
  /** The action description */
  description?: string;
  /** Number of roles that can start this action */
  roleCount: number;
  /** Whether the action data is valid */
  isValid: boolean;
}

/**
 * A unique starting action (deduplicated by action identifier).
 * Multiple roles that can start the same action are counted
 * but not shown as separate entries.
 */
export interface UniqueStartingAction {
  actionIdentifier: string;
  name: string;
  description?: string;
  roleCount: number;
}

/**
 * Role information from a template.
 */
export interface TemplateRole {
  roleId: string;
  name: string;
  description?: string;
}

/**
 * Format a template for display in a list.
 *
 * @param template - The template to format
 * @param index - Optional index for numbered display
 * @returns Formatted item data for display
 */
export function formatTemplateListItem(
  template: XOTemplate | null | undefined,
  index?: number,
): FormattedTemplateItem {
  if (!template) {
    return {
      label: "",
      description: undefined,
      isValid: false,
    };
  }

  const name = template.name || "Unnamed Template";
  const prefix = index !== undefined ? `${index + 1}. ` : "";

  return {
    label: `${prefix}${name}`,
    description: template.description,
    isValid: true,
  };
}

/**
 * Format an action for display in a list.
 *
 * @param actionId - The action identifier
 * @param action - The action definition from the template
 * @param roleCount - Number of roles that can start this action
 * @param index - Optional index for numbered display
 * @returns Formatted item data for display
 */
export function formatActionListItem(
  actionId: string,
  action: XOTemplateAction | null | undefined,
  roleCount: number = 1,
  index?: number,
): FormattedActionItem {
  if (!actionId) {
    return {
      label: "",
      description: undefined,
      roleCount: 0,
      isValid: false,
    };
  }

  const name = action?.name || actionId;
  const prefix = index !== undefined ? `${index + 1}. ` : "";
  const roleSuffix = roleCount > 1 ? ` (${roleCount} roles)` : "";

  return {
    label: `${prefix}${name}${roleSuffix}`,
    description: action?.description,
    roleCount,
    isValid: true,
  };
}

/**
 * Deduplicate starting actions from a template.
 * Multiple roles that can start the same action are counted
 * but returned as a single entry.
 *
 * @param template - The template to process
 * @param startingActions - Array of { action, role } pairs
 * @returns Array of unique starting actions with role counts
 */
export function deduplicateStartingActions(
  template: XOTemplate,
  startingActions: Array<{ action: string; role: string }>,
): UniqueStartingAction[] {
  const actionMap = new Map<string, UniqueStartingAction>();

  for (const sa of startingActions) {
    if (actionMap.has(sa.action)) {
      actionMap.get(sa.action)!.roleCount++;
    } else {
      const actionDef = template.actions?.[sa.action];
      actionMap.set(sa.action, {
        actionIdentifier: sa.action,
        name: actionDef?.name || sa.action,
        description: actionDef?.description,
        roleCount: 1,
      });
    }
  }

  return Array.from(actionMap.values());
}

/**
 * Get all roles from a template.
 *
 * @param template - The template to process
 * @returns Array of role information
 */
export function getTemplateRoles(template: XOTemplate): TemplateRole[] {
  if (!template.roles) return [];

  return Object.entries(template.roles).map(([roleId, role]) => {
    // Handle case where role might be a string instead of object
    const roleObj = typeof role === "object" ? role : null;
    return {
      roleId,
      name: roleObj?.name || roleId,
      description: roleObj?.description,
    };
  });
}

/**
 * Get roles that can start a specific action.
 *
 * @param template - The template to check
 * @param actionIdentifier - The action to check
 * @returns Array of role information for roles that can start this action
 */
export function getRolesForAction(
  template: XOTemplate,
  actionIdentifier: string,
): TemplateRole[] {
  const startEntries = (template.start ?? []).filter(
    (s) => s.action === actionIdentifier,
  );

  return startEntries.map((entry) => {
    const roleDef = template.roles?.[entry.role || ''];
    const roleObj = typeof roleDef === "object" ? roleDef : null;

    // TODO: This is ugly. Lot of conditionals. Need to take a much closer look at this.
    return {
      roleId: entry.role || '',
      name: roleObj?.name || entry.role || '',
      description: roleObj?.description,
    };
  });
}

/**
 * Get template name safely.
 *
 * @param template - The template
 * @returns The template name or a default
 */
export function getTemplateName(
  template: XOTemplate | null | undefined,
): string {
  return template?.name || "Unknown Template";
}

/**
 * Get template description safely.
 *
 * @param template - The template
 * @returns The template description or undefined
 */
export function getTemplateDescription(
  template: XOTemplate | null | undefined,
): string | undefined {
  return template?.description;
}

/**
 * Get action name safely.
 *
 * @param template - The template containing the action
 * @param actionId - The action identifier
 * @returns The action name or the action ID as fallback
 */
export function getActionName(
  template: XOTemplate | null | undefined,
  actionId: string,
): string {
  return template?.actions?.[actionId]?.name || actionId;
}

/**
 * Get action description safely.
 *
 * @param template - The template containing the action
 * @param actionId - The action identifier
 * @returns The action description or undefined
 */
export function getActionDescription(
  template: XOTemplate | null | undefined,
  actionId: string,
): string | undefined {
  return template?.actions?.[actionId]?.description;
}