import {
  IBootstrapService,
  IHostFileSystem,
  IWorkspaceInstanceManager,
  IWorkspaceService,
  IWorkspaceSessions,
  IWorkspaceTrust,
  type Scope,
  type Workspace,
} from '@moonshot-ai/agent-core-v2';
import { isAbsolute, join, normalize, resolve } from 'node:path';

import { z } from 'zod';

import { errEnvelope, okEnvelope } from '../envelope';
import { requestLog } from '../lib/requestLog';
import { defineRoute } from '../middleware/defineRoute';
import { ErrorCode } from '../protocol/error-codes';
import {
  addDirRequestSchema,
  addDirResponseSchema,
  createWorkspaceRequestSchema,
  createWorkspaceResponseSchema,
  deleteWorkspaceResponseSchema,
  listWorkspacesResponseSchema,
  updateWorkspaceRequestSchema,
  updateWorkspaceResponseSchema,
  workspaceIdParamSchema,
  workspaceTrustResponseSchema,
} from '../protocol/rest-workspace';
import type { Workspace as WorkspaceWire } from '../protocol/workspace';

interface WorkspaceRouteHost {
  get(
    path: string,
    options: { preHandler: unknown[]; schema?: Record<string, unknown> } | undefined,
    handler: (
      req: { id: string },
      reply: { send(payload: unknown): unknown },
    ) => Promise<void> | void,
  ): unknown;
  post(
    path: string,
    options: { preHandler: unknown[]; schema?: Record<string, unknown> },
    handler: (
      req: { id: string; body: unknown; params: unknown },
      reply: { send(payload: unknown): unknown },
    ) => Promise<void> | void,
  ): unknown;
  patch(
    path: string,
    options: { preHandler: unknown[]; schema?: Record<string, unknown> },
    handler: (
      req: { id: string; body: unknown; params: unknown },
      reply: { send(payload: unknown): unknown },
    ) => Promise<void> | void,
  ): unknown;
  delete(
    path: string,
    options: { preHandler: unknown[]; schema?: Record<string, unknown> } | undefined,
    handler: (
      req: { id: string; params: unknown },
      reply: { send(payload: unknown): unknown },
    ) => Promise<void> | void,
  ): unknown;
}

const detailsSchema = z.array(z.object({ path: z.string(), message: z.string() }));

export function registerWorkspacesRoutes(app: WorkspaceRouteHost, core: Scope): void {
  const listRoute = defineRoute(
    {
      method: 'GET',
      path: '/workspaces',
      success: { data: listWorkspacesResponseSchema },
      description: 'List registered workspaces',
      tags: ['workspaces'],
    },
    async (req, reply) => {
      const items = await core.accessor.get(IWorkspaceService).list();
      const projected = await Promise.all(items.map((ws) => toWireWorkspace(core, ws)));
      reply.send(okEnvelope({ items: projected }, req.id));
    },
  );
  app.get(listRoute.path, listRoute.options, listRoute.handler as Parameters<WorkspaceRouteHost['get']>[2]);

  const createRoute = defineRoute(
    {
      method: 'POST',
      path: '/workspaces',
      body: createWorkspaceRequestSchema,
      success: { data: createWorkspaceResponseSchema },
      errors: {
        [ErrorCode.VALIDATION_FAILED]: { detailsSchema },
        [ErrorCode.FS_PATH_NOT_FOUND]: {},
      },
      description: 'Register a workspace (idempotent on root)',
      tags: ['workspaces'],
    },
    async (req, reply) => {
      const root = req.body.root;
      if (!isAbsolute(root)) {
        reply.send(
          buildValidationEnvelope(
            [{ path: 'root', message: 'root must be an absolute path' }],
            req.id,
          ),
        );
        return;
      }
      const hostFs = core.accessor.get(IHostFileSystem);
      try {
        const stat = await hostFs.stat(root);
        if (!stat.isDirectory) {
          reply.send(
            errEnvelope(ErrorCode.FS_PATH_NOT_FOUND, `root ${root} is not a directory`, req.id),
          );
          return;
        }
      } catch {
        reply.send(errEnvelope(ErrorCode.FS_PATH_NOT_FOUND, `root ${root} does not exist`, req.id));
        return;
      }
      const ws = await core.accessor.get(IWorkspaceService).createOrTouch(root, req.body.name);
      reply.send(okEnvelope(await toWireWorkspace(core, ws), req.id));
    },
  );
  app.post(
    createRoute.path,
    createRoute.options,
    createRoute.handler as Parameters<WorkspaceRouteHost['post']>[2],
  );

  const updateRoute = defineRoute(
    {
      method: 'PATCH',
      path: '/workspaces/{workspace_id}',
      params: workspaceIdParamSchema,
      body: updateWorkspaceRequestSchema,
      success: { data: updateWorkspaceResponseSchema },
      errors: {
        [ErrorCode.VALIDATION_FAILED]: { detailsSchema },
        [ErrorCode.WORKSPACE_NOT_FOUND]: {},
      },
      description: 'Rename a workspace (display name only)',
      tags: ['workspaces'],
    },
    async (req, reply) => {
      const { workspace_id } = req.params;
      const ws = await core.accessor
        .get(IWorkspaceService)
        .update(workspace_id, { name: req.body.name });
      if (ws === undefined) {
        reply.send(
          errEnvelope(ErrorCode.WORKSPACE_NOT_FOUND, `workspace ${workspace_id} does not exist`, req.id),
        );
        return;
      }
      reply.send(okEnvelope(await toWireWorkspace(core, ws), req.id));
    },
  );
  app.patch(
    updateRoute.path,
    updateRoute.options,
    updateRoute.handler as Parameters<WorkspaceRouteHost['patch']>[2],
  );

  const deleteRoute = defineRoute(
    {
      method: 'DELETE',
      path: '/workspaces/{workspace_id}',
      params: workspaceIdParamSchema,
      success: { data: deleteWorkspaceResponseSchema },
      errors: {
        [ErrorCode.VALIDATION_FAILED]: { detailsSchema },
        [ErrorCode.WORKSPACE_NOT_FOUND]: {},
      },
      description: 'Unregister a workspace (does not remove on-disk content)',
      tags: ['workspaces'],
    },
    async (req, reply) => {
      const { workspace_id } = req.params;
      const registry = core.accessor.get(IWorkspaceService);
      const existing = await registry.get(workspace_id);
      if (existing === undefined) {
        reply.send(
          errEnvelope(ErrorCode.WORKSPACE_NOT_FOUND, `workspace ${workspace_id} does not exist`, req.id),
        );
        return;
      }
      await registry.delete(workspace_id);
      requestLog(req)?.info({ workspace_id }, 'workspace deleted');
      reply.send(okEnvelope({ deleted: true as const }, req.id));
    },
  );
  app.delete(
    deleteRoute.path,
    deleteRoute.options,
    deleteRoute.handler as Parameters<WorkspaceRouteHost['delete']>[2],
  );

  const getTrustRoute = defineRoute(
    {
      method: 'GET',
      path: '/workspaces/{workspace_id}/trust',
      params: workspaceIdParamSchema,
      success: { data: workspaceTrustResponseSchema },
      errors: {
        [ErrorCode.WORKSPACE_NOT_FOUND]: {},
      },
      description: 'Read the workspace trust state',
      tags: ['workspaces'],
    },
    async (req, reply) => {
      const trust = await resolveTrust(core, req.params.workspace_id, req.id, reply);
      if (trust === undefined) return;
      reply.send(okEnvelope({ trusted: await trust.get() }, req.id));
    },
  );
  app.get(
    getTrustRoute.path,
    getTrustRoute.options,
    getTrustRoute.handler as Parameters<WorkspaceRouteHost['get']>[2],
  );

  const trustRoute = defineRoute(
    {
      method: 'POST',
      path: '/workspaces/{workspace_id}/trust',
      params: workspaceIdParamSchema,
      success: { data: workspaceTrustResponseSchema },
      errors: {
        [ErrorCode.WORKSPACE_NOT_FOUND]: {},
      },
      description: 'Mark the workspace trusted (project-level MCP config loads)',
      tags: ['workspaces'],
    },
    async (req, reply) => {
      const trust = await resolveTrust(core, req.params.workspace_id, req.id, reply);
      if (trust === undefined) return;
      await trust.trust();
      reply.send(okEnvelope({ trusted: true }, req.id));
    },
  );
  app.post(
    trustRoute.path,
    trustRoute.options,
    trustRoute.handler as Parameters<WorkspaceRouteHost['post']>[2],
  );

  const untrustRoute = defineRoute(
    {
      method: 'POST',
      path: '/workspaces/{workspace_id}/untrust',
      params: workspaceIdParamSchema,
      success: { data: workspaceTrustResponseSchema },
      errors: {
        [ErrorCode.WORKSPACE_NOT_FOUND]: {},
      },
      description: 'Revoke workspace trust (project-level MCP config unloads)',
      tags: ['workspaces'],
    },
    async (req, reply) => {
      const trust = await resolveTrust(core, req.params.workspace_id, req.id, reply);
      if (trust === undefined) return;
      await trust.untrust();
      reply.send(okEnvelope({ trusted: false }, req.id));
    },
  );
  app.post(
    untrustRoute.path,
    untrustRoute.options,
    untrustRoute.handler as Parameters<WorkspaceRouteHost['post']>[2],
  );

  const addDirRoute = defineRoute(
    {
      method: 'POST',
      path: '/workspaces/{workspace_id}/add-dir',
      params: workspaceIdParamSchema,
      body: addDirRequestSchema,
      success: { data: addDirResponseSchema },
      errors: {
        [ErrorCode.VALIDATION_FAILED]: { detailsSchema },
        [ErrorCode.FS_PATH_NOT_FOUND]: {},
        [ErrorCode.WORKSPACE_NOT_FOUND]: {},
      },
      description: 'Add an additional directory to the workspace',
      tags: ['workspaces'],
    },
    async (req, reply) => {
      const { workspace_id } = req.params;
      const ws = await core.accessor.get(IWorkspaceService).get(workspace_id);
      if (ws === undefined) {
        reply.send(
          errEnvelope(ErrorCode.WORKSPACE_NOT_FOUND, `workspace ${workspace_id} does not exist`, req.id),
        );
        return;
      }
      const resolved = resolveAdditionalDirPath(core, ws.root, req.body.path);
      const hostFs = core.accessor.get(IHostFileSystem);
      try {
        const stat = await hostFs.stat(resolved);
        if (!stat.isDirectory) {
          reply.send(
            errEnvelope(ErrorCode.FS_PATH_NOT_FOUND, `path ${req.body.path} is not a directory`, req.id),
          );
          return;
        }
      } catch {
        reply.send(
          errEnvelope(ErrorCode.FS_PATH_NOT_FOUND, `path ${req.body.path} does not exist`, req.id),
        );
        return;
      }
      const workspace = await core
        .accessor.get(IWorkspaceInstanceManager)
        .getOrCreate({ workspaceId: workspace_id, root: ws.root });
      const result = await workspace.program.dirs.addDir({
        path: req.body.path,
        persist: req.body.persist,
      });
      reply.send(
        okEnvelope(
          {
            project_root: result.projectRoot,
            config_path: result.configPath,
            additional_dirs: [...result.additionalDirs],
            persisted: result.persisted,
          },
          req.id,
        ),
      );
    },
  );
  app.post(
    addDirRoute.path,
    addDirRoute.options,
    addDirRoute.handler as Parameters<WorkspaceRouteHost['post']>[2],
  );
}

function resolveAdditionalDirPath(core: Scope, root: string, input: string): string {
  const trimmed = input.trim();
  const osHomeDir = core.accessor.get(IBootstrapService).osHomeDir;
  const expanded =
    trimmed === '~'
      ? osHomeDir
      : trimmed.startsWith('~/')
        ? join(osHomeDir, trimmed.slice(2))
        : trimmed;
  return isAbsolute(expanded) ? normalize(expanded) : resolve(root, expanded);
}

type TrustReply = { send(payload: unknown): unknown };

async function resolveTrust(
  core: Scope,
  workspaceId: string,
  requestId: string,
  reply: TrustReply,
): Promise<IWorkspaceTrust | undefined> {
  const ws = await core.accessor.get(IWorkspaceService).get(workspaceId);
  if (ws === undefined) {
    reply.send(
      errEnvelope(ErrorCode.WORKSPACE_NOT_FOUND, `workspace ${workspaceId} does not exist`, requestId),
    );
    return undefined;
  }
  const workspace = await core
    .accessor.get(IWorkspaceInstanceManager)
    .getOrCreate({ workspaceId, root: ws.root });
  return workspace.program.trust;
}

export async function toWireWorkspace(core: Scope, ws: Workspace): Promise<WorkspaceWire> {
  const sessionCount = await core.accessor.get(IWorkspaceSessions).count(ws.id);
  return {
    id: ws.id,
    root: ws.root,
    name: ws.name,
    created_at: new Date(ws.createdAt).toISOString(),
    last_opened_at: new Date(ws.lastOpenedAt).toISOString(),
    session_count: sessionCount,
  };
}

function buildValidationEnvelope(
  details: { path: string; message: string }[],
  requestId: string,
): {
  code: number;
  msg: string;
  data: null;
  request_id: string;
  details: { path: string; message: string }[];
} {
  const first = details[0];
  const msg = first === undefined ? 'validation failed' : `${first.path}: ${first.message}`;
  return {
    code: ErrorCode.VALIDATION_FAILED,
    msg,
    data: null,
    request_id: requestId,
    details,
  };
}