import { Request, Response, NextFunction } from "express";
import { z } from "zod";
import { db, policyRules, resourcePolicies } from "@server/db";
import { eq } from "drizzle-orm";
import response from "@server/lib/response";
import HttpCode from "@server/types/HttpCode";
import createHttpError from "http-errors";
import logger from "@server/logger";
import { fromError } from "zod-validation-error";
import {
    isValidCIDR,
    isValidIP,
    isValidUrlGlobPattern
} from "@server/lib/validators";
import { OpenAPITags, registry } from "@server/openApi";

const ruleSchema = z.strictObject({
    action: z.enum(["ACCEPT", "DROP", "PASS"]).openapi({
        type: "string",
        enum: ["ACCEPT", "DROP", "PASS"],
        description: "rule action"
    }),
    match: z.enum(["CIDR", "IP", "PATH"]).openapi({
        type: "string",
        enum: ["CIDR", "IP", "PATH"],
        description: "rule match"
    }),
    value: z.string().min(1),
    priority: z.int().openapi({
        type: "integer",
        description: "Rule priority"
    }),
    enabled: z.boolean().optional()
});

const setResourcePolicyRulesBodySchema = z.strictObject({
    applyRules: z.boolean(),
    rules: z.array(ruleSchema)
});

const setResourcePolicyRulesParamsSchema = z.strictObject({
    resourcePolicyId: z.string().transform(Number).pipe(z.int().positive())
});

registry.registerPath({
    method: "put",
    path: "/resource-policy/{resourcePolicyId}/rules",
    description:
        "Set all rules for a resource policy at once. This will replace all existing rules.",
    tags: [OpenAPITags.Policy],
    request: {
        params: setResourcePolicyRulesParamsSchema,
        body: {
            content: {
                "application/json": {
                    schema: setResourcePolicyRulesBodySchema
                }
            }
        }
    },
    responses: {}
});

export async function setResourcePolicyRules(
    req: Request,
    res: Response,
    next: NextFunction
): Promise<any> {
    try {
        const parsedParams = setResourcePolicyRulesParamsSchema.safeParse(
            req.params
        );
        if (!parsedParams.success) {
            return next(
                createHttpError(
                    HttpCode.BAD_REQUEST,
                    fromError(parsedParams.error).toString()
                )
            );
        }

        const parsedBody = setResourcePolicyRulesBodySchema.safeParse(req.body);
        if (!parsedBody.success) {
            return next(
                createHttpError(
                    HttpCode.BAD_REQUEST,
                    fromError(parsedBody.error).toString()
                )
            );
        }

        const { resourcePolicyId } = parsedParams.data;
        const { applyRules, rules } = parsedBody.data;

        const [policy] = await db
            .select()
            .from(resourcePolicies)
            .where(eq(resourcePolicies.resourcePolicyId, resourcePolicyId))
            .limit(1);

        if (!policy) {
            return next(
                createHttpError(HttpCode.NOT_FOUND, "Resource policy not found")
            );
        }

        for (const rule of rules) {
            if (rule.match === "CIDR" && !isValidCIDR(rule.value)) {
                return next(
                    createHttpError(
                        HttpCode.BAD_REQUEST,
                        "Invalid CIDR provided"
                    )
                );
            } else if (rule.match === "IP" && !isValidIP(rule.value)) {
                return next(
                    createHttpError(HttpCode.BAD_REQUEST, "Invalid IP provided")
                );
            } else if (
                rule.match === "PATH" &&
                !isValidUrlGlobPattern(rule.value)
            ) {
                return next(
                    createHttpError(
                        HttpCode.BAD_REQUEST,
                        "Invalid URL glob pattern provided"
                    )
                );
            }
        }

        await db.transaction(async (trx) => {
            await trx
                .update(resourcePolicies)
                .set({ applyRules })
                .where(eq(resourcePolicies.resourcePolicyId, resourcePolicyId));

            await trx
                .delete(policyRules)
                .where(eq(policyRules.resourcePolicyId, resourcePolicyId));

            if (rules.length > 0) {
                await trx.insert(policyRules).values(
                    rules.map((rule) => ({
                        resourcePolicyId,
                        ...rule
                    }))
                );
            }
        });

        return response(res, {
            data: {},
            success: true,
            error: false,
            message: "Resource policy rules set successfully",
            status: HttpCode.OK
        });
    } catch (error) {
        logger.error(error);
        return next(
            createHttpError(HttpCode.INTERNAL_SERVER_ERROR, "An error occurred")
        );
    }
}