/* eslint-disable */
import dotenv from "dotenv";
import path from "path";
import knex from "knex";
import { writeFileSync } from "fs";

dotenv.config({
  path: path.join(__dirname, "../../.env.migration")
});

const db = knex({
  client: "pg",
  connection: process.env.DB_CONNECTION_URI
});

const getZodPrimitiveType = (type: string) => {
  switch (type) {
    case "uuid":
      return "z.string().uuid()";
    case "character varying":
      return "z.string()";
    case "ARRAY":
      return "z.string().array()";
    case "boolean":
      return "z.boolean()";
    case "jsonb":
      return "z.unknown()";
    case "json":
      return "z.unknown()";
    case "timestamp with time zone":
      return "z.date()";
    case "integer":
      return "z.number()";
    case "bigint":
      return "z.coerce.number()";
    case "text":
      return "z.string()";
    case "bytea":
      return "zodBuffer";
    default:
      throw new Error(`Invalid type: ${type}`);
  }
};

const getZodDefaultValue = (type: unknown, value: string | number | boolean | Object) => {
  if (!value || value === "null") return;
  switch (type) {
    case "uuid":
      return `.default("00000000-0000-0000-0000-000000000000")`;
    case "character varying": {
      if (value === "gen_random_uuid()") return;
      if (typeof value === "string" && value.includes("::")) {
        return `.default(${value.split("::")[0]})`;
      }
      return `.default(${value})`;
    }
    case "ARRAY":
      return `.default(${value})`;
    case "boolean":
      return `.default(${value})`;
    case "jsonb":
      return "z.string()";
    case "json":
      return "z.string()";
    case "timestamp with time zone": {
      if (value === "CURRENT_TIMESTAMP") return;
      return "z.string().datetime()";
    }
    case "integer": {
      if ((value as string).includes("nextval")) return;
      return `.default(${value})`;
    }
    case "bigint": {
      if ((value as string).includes("nextval")) return;
      return `.default(${parseInt((value as string).split("::")[0].slice(1, -1), 10)})`;
    }
    case "text":
      if (typeof value === "string" && value.includes("::")) {
        return `.default(${value.split("::")[0]})`;
      }
      return `.default(${value})`;
    default:
      throw new Error(`Invalid type: ${type}`);
  }
};

const bigIntegerColumns: Record<string, string[]> = {
  "folder_commits": ["commitId"]
};


const main = async () => {
  const tables = (
    await db("information_schema.tables")
      .whereRaw("table_schema =  current_schema()")
      .select<{ tableName: string }[]>("table_name as tableName")
      .orderBy("table_name")
  ).filter(
    (el) =>
      !el.tableName.includes("_migrations") &&
      !el.tableName.includes("audit_logs_") &&
      el.tableName !== "intermediate_audit_logs"
  );

  for (let i = 0; i < tables.length; i += 1) {
    const { tableName } = tables[i];
    const columns = await db(tableName).columnInfo();
    const columnNames = Object.keys(columns);

    let schema = "";
    const zodImportSet = new Set<string>();
    for (let colNum = 0; colNum < columnNames.length; colNum++) {
      const columnName = columnNames[colNum];
      const colInfo = columns[columnName];
      let ztype = getZodPrimitiveType(colInfo.type);
      if (bigIntegerColumns[tableName]?.includes(columnName)) {
        ztype = "z.coerce.bigint()";
      }
      if (["zodBuffer"].includes(ztype)) {
        zodImportSet.add(ztype);
      }

      // don't put optional on id
      if (colInfo.defaultValue && columnName !== "id") {
        const { defaultValue } = colInfo;
        const zSchema = getZodDefaultValue(colInfo.type, defaultValue);
        if (zSchema) {
          ztype = ztype.concat(zSchema);
        }
      }
      if (colInfo.nullable) {
        ztype = ztype.concat(".nullable().optional()");
      }
      schema = schema.concat(
        `${!schema ? "\n" : ""}  ${columnName}: ${ztype}${colNum === columnNames.length - 1 ? "" : ","}\n`
      );
    }

    const dashcase = tableName.split("_").join("-");
    const pascalCase = tableName
      .split("_")
      .reduce((prev, curr) => prev + `${curr.at(0)?.toUpperCase()}${curr.slice(1).toLowerCase()}`, "");

    const zodImports = Array.from(zodImportSet);

    // the insert and update are changed to zod input type to use default cases
    writeFileSync(
      path.join(__dirname, "../src/db/schemas", `${dashcase}.ts`),
      `// Code generated by automation script, DO NOT EDIT.
// Automated by pulling database and generating zod schema
// To update. Just run npm run generate:schema
// Written by akhilmhdh.

import { z } from "zod";

${zodImports.length ? `import { ${zodImports.join(",")} } from \"@app/lib/zod\";` : ""}

import { TImmutableDBKeys } from "./models";

export const ${pascalCase}Schema = z.object({${schema}});

export type T${pascalCase} = z.infer<typeof ${pascalCase}Schema>;
export type T${pascalCase}Insert = Omit<z.input<typeof ${pascalCase}Schema>, TImmutableDBKeys>;
export type T${pascalCase}Update = Partial<Omit<z.input<typeof ${pascalCase}Schema>, TImmutableDBKeys>>;
`
    );
  }

  process.exit(0);
};

main();