import type { Tool } from "@modelcontextprotocol/sdk/types.js";
import {
  loadManifest,
  generateManifest,
} from "@mandujs/core";
import { getProjectPaths, isInsideProject, readJsonFile } from "../utils/project.js";
import path from "path";
import fs from "fs/promises";

export const specToolDefinitions: Tool[] = [
  {
    name: "mandu.route.list",
    description:
      "List all routes from .mandu/routes.manifest.json with their kind, pattern, slotModule, and contractModule.",
    annotations: {
      readOnlyHint: true,
    },
    inputSchema: {
      type: "object",
      properties: {},
      required: [],
    },
  },
  {
    name: "mandu.route.get",
    description:
      "Get full details of a specific route by its ID. Use before modifying a route.",
    annotations: {
      readOnlyHint: true,
    },
    inputSchema: {
      type: "object",
      properties: {
        routeId: {
          type: "string",
          description: "The route ID to retrieve (use mandu.route.list to see all IDs)",
        },
      },
      required: ["routeId"],
    },
  },
  {
    name: "mandu.route.boundaries",
    description:
      "Inspect compiler-discovered client boundary metadata for one route or all routes, including route manifest records and optional bundle manifest entries.",
    annotations: {
      readOnlyHint: true,
    },
    inputSchema: {
      type: "object",
      properties: {
        routeId: {
          type: "string",
          description: "Optional route ID to inspect. Omit to list boundaries for all routes.",
        },
        includeBundle: {
          type: "boolean",
          description: "When true, also correlate route boundaries with .mandu/manifest.json boundary bundle entries.",
        },
      },
      required: [],
    },
  },
  {
    name: "mandu.route.add",
    description:
      "Scaffold a new route in app/ with optional slot and contract files, then regenerate the manifest.",
    annotations: {
      destructiveHint: false,
      readOnlyHint: false,
    },
    inputSchema: {
      type: "object",
      properties: {
        path: {
          type: "string",
          description: "Route path relative to app/ (e.g., 'api/users' or 'blog/[slug]')",
        },
        kind: {
          type: "string",
          enum: ["api", "page"],
          description: "Route type: 'api' creates route.ts with HTTP handlers, 'page' creates page.tsx with a React component",
        },
        withSlot: {
          type: "boolean",
          description: "Also scaffold a server-side data loader at spec/slots/{routeId}.slot.ts (default: true)",
        },
        withContract: {
          type: "boolean",
          description: "Also scaffold a Zod contract at spec/contracts/{routeId}.contract.ts (default: false)",
        },
      },
      required: ["path", "kind"],
    },
  },
  {
    name: "mandu.route.delete",
    description:
      "Delete a route's app/ source file and regenerate the manifest. Slot and contract files are preserved.",
    annotations: {
      destructiveHint: true,
      readOnlyHint: false,
    },
    inputSchema: {
      type: "object",
      properties: {
        routeId: {
          type: "string",
          description: "The route ID to delete (use mandu.route.list to find it)",
        },
      },
      required: ["routeId"],
    },
  },
  {
    name: "mandu.manifest.validate",
    description:
      "Validate the routes manifest for structural integrity. Run after manual edits or when routes behave unexpectedly.",
    annotations: {
      readOnlyHint: true,
    },
    inputSchema: {
      type: "object",
      properties: {},
      required: [],
    },
  },
];

export function specTools(projectRoot: string) {
  const paths = getProjectPaths(projectRoot);

  const handlers: Record<string, (args: Record<string, unknown>) => Promise<unknown>> = {
    "mandu.route.list": async () => {
      const result = await loadManifest(paths.manifestPath);
      if (!result.success || !result.data) {
        return { error: result.errors };
      }

      return {
        version: result.data.version,
        routes: result.data.routes.map((r) => ({
          id: r.id,
          pattern: r.pattern,
          kind: r.kind,
          slotModule: r.slotModule,
          contractModule: r.contractModule,
          componentModule: r.componentModule,
        })),
        count: result.data.routes.length,
      };
    },

    "mandu.route.get": async (args: Record<string, unknown>) => {
      const { routeId } = args as { routeId: string };

      const result = await loadManifest(paths.manifestPath);
      if (!result.success || !result.data) {
        return { error: result.errors };
      }

      const route = result.data.routes.find((r) => r.id === routeId);
      if (!route) {
        return { error: `Route not found: ${routeId}` };
      }

      return { route };
    },

    "mandu.route.boundaries": async (args: Record<string, unknown>) => {
      const { routeId, includeBundle = false } = args as { routeId?: string; includeBundle?: boolean };

      const result = await loadManifest(paths.manifestPath);
      if (!result.success || !result.data) {
        return { error: result.errors };
      }

      const bundleManifestPath = path.join(projectRoot, ".mandu", "manifest.json");
      const bundleManifest = includeBundle
        ? await readJsonFile<{
            boundaries?: Record<string, {
              route?: string;
              js?: string;
              module?: string;
              exportName?: string;
              priority?: string;
              hydrate?: string;
            }>;
          }>(bundleManifestPath)
        : null;

      const routes = routeId
        ? result.data.routes.filter((route) => route.id === routeId)
        : result.data.routes;

      if (routeId && routes.length === 0) {
        return { error: `Route not found: ${routeId}` };
      }

      const inspected = routes.map((route) => {
        const boundaries = route.boundaries ?? [];
        const diagnostics: Array<{
          code: string;
          severity: "warning";
          message: string;
          routeId: string;
          boundaryId?: string;
        }> = [];

        if (includeBundle && boundaries.length > 0 && !bundleManifest) {
          diagnostics.push({
            code: "MANDU_BOUNDARY_BUNDLE_MANIFEST_MISSING",
            severity: "warning",
            message: "Route has compiler-discovered client boundaries, but .mandu/manifest.json was not found. Run mandu build to inspect generated boundary chunks.",
            routeId: route.id,
          });
        }

        const boundaryRecords = boundaries.map((boundary) => {
          const bundle = bundleManifest?.boundaries?.[boundary.id];
          if (includeBundle && bundleManifest && !bundle) {
            diagnostics.push({
              code: "MANDU_BOUNDARY_BUNDLE_ENTRY_MISSING",
              severity: "warning",
              message: `Boundary '${boundary.id}' is present in routes manifest but missing from .mandu/manifest.json boundaries.`,
              routeId: route.id,
              boundaryId: boundary.id,
            });
          }

          return {
            id: boundary.id,
            routeId: boundary.routeId,
            module: boundary.module,
            importSpecifier: boundary.importSpecifier,
            exportName: boundary.exportName,
            localName: boundary.localName,
            hydrate: boundary.hydrate,
            ordinal: boundary.ordinal,
            propsSource: boundary.propsSource,
            propsKeys: boundary.propsKeys ?? [],
            hasSpreadProps: !!boundary.hasSpreadProps,
            source: boundary.source,
            bundle: bundle
              ? {
                  js: bundle.js ?? null,
                  priority: bundle.priority ?? null,
                  hydrate: bundle.hydrate ?? null,
                }
              : null,
          };
        });

        return {
          routeId: route.id,
          pattern: route.pattern,
          module: route.module,
          boundaryCount: boundaryRecords.length,
          boundaries: boundaryRecords,
          diagnostics,
        };
      });

      return {
        source: {
          routesManifest: ".mandu/routes.manifest.json",
          bundleManifest: includeBundle && bundleManifest ? ".mandu/manifest.json" : null,
        },
        includeBundle,
        routeId: routeId ?? null,
        routeCount: inspected.length,
        boundaryCount: inspected.reduce((count, route) => count + route.boundaryCount, 0),
        routes: inspected,
      };
    },

    "mandu.route.add": async (args: Record<string, unknown>) => {
      const { path: routePath, kind, withSlot = true, withContract = false } = args as {
        path: string;
        kind: "api" | "page";
        withSlot?: boolean;
        withContract?: boolean;
      };

      const createdFiles: string[] = [];
      const normalizedRoutePath = normalizeRoutePath(routePath);
      if (!normalizedRoutePath) {
        return {
          error: "Route path must be a non-empty relative path inside app/",
        };
      }

      // Scaffold app/ file
      const fileName = kind === "api" ? "route.ts" : "page.tsx";
      const appFilePath = path.resolve(paths.appDir, normalizedRoutePath, fileName);
      if (!isInsideProject(appFilePath, paths.appDir)) {
        return {
          error: "Route path resolves outside app/",
        };
      }
      if (await Bun.file(appFilePath).exists()) {
        return {
          error: `Route source already exists: app/${normalizedRoutePath}/${fileName}`,
        };
      }
      const appFileDir = path.dirname(appFilePath);

      await fs.mkdir(appFileDir, { recursive: true });

      if (kind === "api") {
        await Bun.write(appFilePath, `export function GET(req: Request) {\n  return Response.json({ message: "Hello" });\n}\n`);
      } else {
        await Bun.write(appFilePath, `export default function Page() {\n  return <div>Page</div>;\n}\n`);
      }
      createdFiles.push(`app/${normalizedRoutePath}/${fileName}`);

      // Derive route ID from path
      const routeId = normalizedRoutePath.replace(/\//g, "-").replace(/[\[\]\.]/g, "");

      // Scaffold slot if requested
      if (withSlot) {
        const slotPath = path.join(paths.slotsDir, `${routeId}.slot.ts`);
        await fs.mkdir(paths.slotsDir, { recursive: true });
        if (!(await Bun.file(slotPath).exists())) {
          await Bun.write(slotPath, `export default function slot(req: Request) {\n  return {};\n}\n`);
          createdFiles.push(`spec/slots/${routeId}.slot.ts`);
        }
      }

      // Scaffold contract if requested
      if (withContract) {
        const contractPath = path.join(paths.contractsDir, `${routeId}.contract.ts`);
        await fs.mkdir(paths.contractsDir, { recursive: true });
        if (!(await Bun.file(contractPath).exists())) {
          await Bun.write(contractPath, `import { z } from "zod";\n\nexport const contract = {\n  request: z.object({}),\n  response: z.object({}),\n};\n`);
          createdFiles.push(`spec/contracts/${routeId}.contract.ts`);
        }
      }

      // Rescan to regenerate manifest with auto-linking
      const genResult = await generateManifest(projectRoot);

      return {
        success: true,
        routeId,
        createdFiles,
        totalRoutes: genResult.manifest.routes.length,
        message: `Route '${routeId}' scaffolded successfully`,
        relatedSkills: ["mandu-create-feature"],
      };
    },

    "mandu.route.delete": async (args: Record<string, unknown>) => {
      const { routeId } = args as { routeId: string };

      // Load current manifest to find the route
      const result = await loadManifest(paths.manifestPath);
      if (!result.success || !result.data) {
        return { error: result.errors };
      }

      const route = result.data.routes.find((r) => r.id === routeId);
      if (!route) {
        return { error: `Route not found: ${routeId}` };
      }

      // Delete app/ source file (module path points to generated; need to find source)
      const deletedFiles: string[] = [];
      if (route.module && route.module.startsWith("app/")) {
        const fullPath = path.join(projectRoot, route.module);
        try {
          await fs.unlink(fullPath);
          deletedFiles.push(route.module);
        } catch {}
      }

      // Rescan manifest (slot/contract files preserved)
      const genResult = await generateManifest(projectRoot);

      return {
        success: true,
        deletedRoute: route,
        deletedFiles,
        preservedFiles: [route.slotModule, route.contractModule].filter(Boolean),
        totalRoutes: genResult.manifest.routes.length,
        message: `Route '${routeId}' deleted from app/. Slot/contract files preserved.`,
      };
    },

    "mandu.manifest.validate": async () => {
      const result = await loadManifest(paths.manifestPath);
      if (!result.success) {
        return {
          valid: false,
          errors: result.errors,
        };
      }

      return {
        valid: true,
        routeCount: result.data?.routes.length || 0,
        version: result.data?.version,
      };
    },
  };

  // Backward-compatible aliases (deprecated)
  handlers["mandu_list_routes"] = handlers["mandu.route.list"];
  handlers["mandu_get_route"] = handlers["mandu.route.get"];
  handlers["mandu_add_route"] = handlers["mandu.route.add"];
  handlers["mandu_delete_route"] = handlers["mandu.route.delete"];
  handlers["mandu_validate_manifest"] = handlers["mandu.manifest.validate"];

  return handlers;
}

function normalizeRoutePath(value: unknown): string | null {
  if (typeof value !== "string") return null;
  const trimmed = value.trim().replace(/\\/g, "/");
  const withoutAppPrefix = trimmed.replace(/^app\//, "");
  const normalized = withoutAppPrefix.replace(/^\/+|\/+$/g, "");
  if (!normalized) return null;

  const segments = normalized.split("/").filter(Boolean);
  if (segments.length === 0) return null;
  if (segments.some((segment) => segment === "." || segment === ".." || segment.includes(":") || segment.includes("\0"))) {
    return null;
  }

  return segments.join("/");
}