import type { DatabaseSync } from "node:sqlite";
import { DEFAULT_CONNECTOR_ACCOUNT_LABEL } from "../../../shared/commands/composio";
import { createId } from "../../../shared/ids";
import { canonicalJson } from "./connector-executions";

export const DEFAULT_ACCOUNT_LABEL = DEFAULT_CONNECTOR_ACCOUNT_LABEL;
const MAX_LABEL_CHARS = 40;

export interface ConnectorAccountRow {
  id: string;
  orgId: string;
  toolkitSlug: string;
  toolkitName: string;
  label: string;
  status: string;
}

export interface ConnectorGrantRow {
  id: string;
  orgId: string;
  agentId: string;
  toolkitSlug: string;
  accountLabel: string;
  limits: ConnectorGrantLimits;
}

/** What a grant narrows the toolkit to: only these actions, and these argument values on every call; null means no limit. */
export interface ConnectorGrantLimits {
  actions: string[] | null;
  fixedArguments: Record<string, unknown> | null;
}

const NO_LIMITS: ConnectorGrantLimits = { actions: null, fixedArguments: null };

/** Which agents may use which labelled company accounts: the CEO all active ones by role, others one per toolkit by grant. */
export class ConnectorGrantsService {
  constructor(private readonly db: DatabaseSync) {}

  grant(input: { orgId: string; agentId: string; toolkitSlug: string; accountLabel: string | null; limits: ConnectorGrantLimits; grantedByType: "agent" | "employee"; grantedById: string | null }): string {
    const agent = this.db.prepare("select id from agents where id = ? and org_id = ? and lifecycle = 'active'")
      .get(input.agentId, input.orgId);
    if (!agent) throw new Error("Grant target must be an active agent in this organization.");
    if (input.grantedByType === "employee" && !this.db.prepare("select id from employees where id = ? and org_id = ?").get(input.grantedById, input.orgId)) {
      throw new Error("A grant by an employee must name an employee of this organization.");
    }
    const slug = normalizeSlug(input.toolkitSlug);
    const label = this.chooseAccount(input.orgId, slug, input.accountLabel).label;
    const actions = input.limits.actions === null ? null : JSON.stringify(normalizeActionNames(input.limits.actions));
    const fixed = input.limits.fixedArguments === null ? null : JSON.stringify(input.limits.fixedArguments);
    this.db.prepare(`
      insert into agent_connector_grants(id, org_id, agent_id, toolkit_slug, account_label, allowed_actions, fixed_arguments, granted_by_type, granted_by_id, created_at)
      values (?, ?, ?, ?, ?, ?, ?, ?, ?, ?)
      on conflict(org_id, agent_id, toolkit_slug) do update set
        account_label = excluded.account_label,
        allowed_actions = excluded.allowed_actions,
        fixed_arguments = excluded.fixed_arguments,
        granted_by_type = excluded.granted_by_type,
        granted_by_id = excluded.granted_by_id
    `).run(createId("cgr"), input.orgId, input.agentId, slug, label, actions, fixed, input.grantedByType, input.grantedById, new Date().toISOString());
    console.info(`[connectors] ${input.grantedByType} ${input.grantedById} granted ${slug}/${label} to ${input.agentId}`);
    return label;
  }

  /** A board grant from the Connectors page: whole access for an agent holding none of the toolkit, never replacing a grant the CEO shaped. */
  grantFromBoard(input: { orgId: string; agentId: string; toolkitSlug: string; accountLabel: string; employeeId: string }): string {
    const slug = normalizeSlug(input.toolkitSlug);
    const held = this.db.prepare("select account_label from agent_connector_grants where org_id = ? and agent_id = ? and toolkit_slug = ?")
      .get(input.orgId, input.agentId, slug) as { account_label: string } | undefined;
    if (held) throw new Error(`This agent already holds ${slug} through its "${held.account_label}" account; revoke that grant first.`);
    return this.grant({ orgId: input.orgId, agentId: input.agentId, toolkitSlug: slug, accountLabel: input.accountLabel, limits: NO_LIMITS, grantedByType: "employee", grantedById: input.employeeId });
  }

  revoke(input: { orgId: string; agentId: string; toolkitSlug: string }): void {
    this.db.prepare("delete from agent_connector_grants where org_id = ? and agent_id = ? and toolkit_slug = ?")
      .run(input.orgId, input.agentId, normalizeSlug(input.toolkitSlug));
    console.info(`[connectors] revoked ${normalizeSlug(input.toolkitSlug)} from ${input.agentId}`);
  }

  /** Toolkits this agent may use: every active one for the CEO; for others, those whose granted account is active. */
  toolkitsForAgent(orgId: string, agentId: string): string[] {
    if (this.isCeo(orgId, agentId)) {
      return [...new Set(this.activeAccounts(orgId).map((account) => account.toolkitSlug))];
    }
    const rows = this.db.prepare(`
      select g.toolkit_slug as slug
      from agent_connector_grants g
      join connector_accounts a on a.org_id = g.org_id and a.toolkit_slug = g.toolkit_slug and a.label = g.account_label and a.status = 'ACTIVE'
      where g.org_id = ? and g.agent_id = ?
      order by g.toolkit_slug asc
    `).all(orgId, agentId) as Array<{ slug: string }>;
    return rows.map((row) => row.slug);
  }

  /** The active account this agent acts through for a toolkit; the CEO names one when the toolkit has several. */
  accountForAgent(orgId: string, agentId: string, toolkitSlug: string, accountLabel: string | null): ConnectorAccountRow {
    const slug = normalizeSlug(toolkitSlug);
    if (this.isCeo(orgId, agentId)) return this.chooseAccount(orgId, slug, accountLabel);
    const grant = this.db.prepare("select account_label from agent_connector_grants where org_id = ? and agent_id = ? and toolkit_slug = ?")
      .get(orgId, agentId, slug) as { account_label: string } | undefined;
    if (!grant) throw new Error(`You have no grant for the "${slug}" connector. Ask the CEO to grant it to you (grant_connector).`);
    if (accountLabel !== null && normalizeAccountLabel(accountLabel) !== grant.account_label) {
      throw new Error(`Your grant for "${slug}" is the "${grant.account_label}" account, not "${accountLabel}".`);
    }
    const account = this.activeAccounts(orgId).find((row) => row.toolkitSlug === slug && row.label === grant.account_label);
    if (!account) throw new Error(`The "${slug}" account "${grant.account_label}" is no longer connected. Ask the board to reconnect it on the Connectors page.`);
    return account;
  }

  /** The limits this agent works under on a toolkit; the CEO has none. */
  limitsForAgent(orgId: string, agentId: string, toolkitSlug: string): ConnectorGrantLimits {
    if (this.isCeo(orgId, agentId)) return NO_LIMITS;
    const row = this.db.prepare("select allowed_actions, fixed_arguments from agent_connector_grants where org_id = ? and agent_id = ? and toolkit_slug = ?")
      .get(orgId, agentId, normalizeSlug(toolkitSlug)) as { allowed_actions: string | null; fixed_arguments: string | null } | undefined;
    if (!row) throw new Error(`You have no grant for the "${toolkitSlug}" connector. Ask the CEO to grant it to you (grant_connector).`);
    return parseLimits(row.allowed_actions, row.fixed_arguments);
  }

  activeAccounts(orgId: string): ConnectorAccountRow[] {
    const rows = this.db.prepare(`
      select id, org_id, toolkit_slug, toolkit_name, label, status
      from connector_accounts
      where org_id = ? and status = 'ACTIVE'
      order by toolkit_slug asc, label asc
    `).all(orgId) as Array<{ id: string; org_id: string; toolkit_slug: string; toolkit_name: string; label: string; status: string }>;
    return rows.map((row) => ({
      id: row.id,
      orgId: row.org_id,
      toolkitSlug: row.toolkit_slug,
      toolkitName: row.toolkit_name,
      label: row.label,
      status: row.status,
    }));
  }

  grantsForOrg(orgId: string): ConnectorGrantRow[] {
    const rows = this.db.prepare(`
      select id, org_id, agent_id, toolkit_slug, account_label, allowed_actions, fixed_arguments
      from agent_connector_grants
      where org_id = ?
      order by toolkit_slug asc
    `).all(orgId) as Array<{ id: string; org_id: string; agent_id: string; toolkit_slug: string; account_label: string; allowed_actions: string | null; fixed_arguments: string | null }>;
    return rows.map((row) => ({
      id: row.id,
      orgId: row.org_id,
      agentId: row.agent_id,
      toolkitSlug: row.toolkit_slug,
      accountLabel: row.account_label,
      limits: parseLimits(row.allowed_actions, row.fixed_arguments),
    }));
  }

  /** The named active account of a toolkit, or its only one; several accounts with no name is an error that lists them. */
  private chooseAccount(orgId: string, slug: string, accountLabel: string | null): ConnectorAccountRow {
    const accounts = this.activeAccounts(orgId).filter((account) => account.toolkitSlug === slug);
    if (accounts.length === 0) throw new Error(`No active connection for toolkit "${slug}". Connect it on the Connectors page first.`);
    const labels = accounts.map((account) => account.label).join(", ");
    if (accountLabel === null) {
      if (accounts.length > 1) throw new Error(`"${slug}" has several accounts (${labels}); name one with account.`);
      return accounts[0];
    }
    const label = normalizeAccountLabel(accountLabel);
    const account = accounts.find((row) => row.label === label);
    if (!account) throw new Error(`"${slug}" has no active account "${label}"; its accounts: ${labels}.`);
    return account;
  }

  private isCeo(orgId: string, agentId: string): boolean {
    const acting = this.db.prepare("select role_level from agents where id = ? and org_id = ?")
      .get(agentId, orgId) as { role_level: string } | undefined;
    return acting?.role_level === "c_suite";
  }
}

export function normalizeSlug(slug: string): string {
  const normalized = slug.trim().toLowerCase();
  if (!normalized) throw new Error("Toolkit slug is required.");
  return normalized;
}

/** Why a call breaks a grant's limits, or null when it keeps them; an action that cannot take a fixed argument could reach past it, so it is refused. */
export function grantLimitRefusal(
  limits: ConnectorGrantLimits,
  toolkit: string,
  action: { name: string; parameters: Record<string, unknown> },
  input: Record<string, unknown>,
): string | null {
  const name = action.name.toUpperCase();
  if (limits.actions && !limits.actions.includes(name)) {
    return `Your grant for ${toolkit} allows only ${limits.actions.join(", ")}; ${name} is not among them.`;
  }
  const properties = (action.parameters.properties ?? {}) as Record<string, unknown>;
  for (const [key, value] of Object.entries(limits.fixedArguments ?? {})) {
    if (!Object.hasOwn(properties, key)) return `Your grant for ${toolkit} is limited to ${key}=${JSON.stringify(value)}, and ${name} takes no ${key}.`;
    if (!Object.hasOwn(input, key)) return `Your grant for ${toolkit} is limited to ${key}=${JSON.stringify(value)}; pass ${key} with that value.`;
    if (canonicalJson(input[key]) !== canonicalJson(value)) {
      return `Your grant for ${toolkit} is limited to ${key}=${JSON.stringify(value)}; this call has ${key}=${JSON.stringify(input[key])}.`;
    }
  }
  return null;
}

/** Whether a grant's action list lets an agent see an action at all. */
export function grantAllowsAction(limits: ConnectorGrantLimits, actionName: string): boolean {
  return limits.actions === null || limits.actions.includes(actionName.toUpperCase());
}

function normalizeActionNames(actions: string[]): string[] {
  const names = actions.map((action) => action.trim().toUpperCase());
  if (names.length === 0 || names.some((name) => !name)) throw new Error("actions must name at least one action, none blank.");
  return [...new Set(names)];
}

function parseLimits(actions: string | null, fixedArguments: string | null): ConnectorGrantLimits {
  return {
    actions: actions === null ? null : JSON.parse(actions) as string[],
    fixedArguments: fixedArguments === null ? null : JSON.parse(fixedArguments) as Record<string, unknown>,
  };
}

/** Account labels are trimmed and lower-case so "Sales" and "sales " name the same account. */
export function normalizeAccountLabel(label: string): string {
  const normalized = label.trim().toLowerCase();
  if (!normalized) throw new Error("Account label is required.");
  if (normalized.length > MAX_LABEL_CHARS) throw new Error(`Account label must be at most ${MAX_LABEL_CHARS} characters.`);
  return normalized;
}