import { events } from "$sb/plugos-syscall/mod.ts";
import { CompleteEvent } from "$sb/app_event.ts";
import { buildHandebarOptions } from "./util.ts";
import type { PageMeta } from "../../web/types.ts";
import { index } from "$sb/silverbullet-syscall/mod.ts";

const builtinAttributes: Record<string, Record<string, string>> = {
  page: {
    name: "string",
    lastModified: "number",
    perm: "rw|ro",
    contentType: "string",
    size: "number",
    tags: "array",
  },
  task: {
    name: "string",
    done: "boolean",
    page: "string",
    deadline: "string",
    pos: "number",
    tags: "array",
  },
  item: {
    name: "string",
    page: "string",
    pos: "number",
    tags: "array",
  },
  tag: {
    name: "string",
    freq: "number",
  },
};

export async function queryComplete(completeEvent: CompleteEvent) {
  const querySourceMatch = /#query\s+([\w\-_]*)$/.exec(
    completeEvent.linePrefix,
  );
  if (querySourceMatch) {
    const allEvents = await events.listEvents();

    return {
      from: completeEvent.pos - querySourceMatch[1].length,
      options: allEvents
        .filter((eventName) => eventName.startsWith("query:"))
        .map((source) => ({
          label: source.substring("query:".length),
        })),
    };
  }

  if (completeEvent.parentNodes.includes("DirectiveStart")) {
    const querySourceMatch = /#query\s+([\w\-_]+)/.exec(
      completeEvent.linePrefix,
    );
    const whereMatch =
      /(where|order\s+by|and|select(\s+[\w\s,]+)?)\s+([\w\-_]*)$/.exec(
        completeEvent.linePrefix,
      );
    if (querySourceMatch && whereMatch) {
      const type = querySourceMatch[1];
      const attributePrefix = whereMatch[3];
      // console.log("Type", type);
      // console.log("Where", attributePrefix);
      const allAttributes = await index.queryPrefix(
        `attr:${type}:`,
      );

      return {
        from: completeEvent.pos - attributePrefix.length,
        options: compileAttributeCompletions(allAttributes, type),
      };
    }
  }
  return null;
}

function compileAttributeCompletions(
  allAttributes: { key: string; value: any }[],
  type?: string,
) {
  let allCompletions: any[] = allAttributes.map((attr) => {
    const [_prefix, context, name] = attr.key.split(":");
    return {
      label: name,
      detail: `${attr.value.type} (${context})`,
      type: "attribute",
    };
  });
  const allContexts = type ? [type] : Object.keys(builtinAttributes);

  for (const context of allContexts) {
    allCompletions = allCompletions.concat(
      builtinAttributes[context]
        ? Object.entries(
          builtinAttributes[context],
        ).map(([name, type]) => ({
          label: name,
          detail: `${type} (${context}: builtin)`,
          type: "attribute",
        }))
        : [],
    );
  }
  return allCompletions;
}

export async function templateVariableComplete(completeEvent: CompleteEvent) {
  const match = /\{\{([\w@]*)$/.exec(completeEvent.linePrefix);
  if (!match) {
    return null;
  }

  const handlebarOptions = buildHandebarOptions({ name: "" } as PageMeta);
  let allCompletions: any[] = Object.keys(handlebarOptions.helpers).map(
    (name) => ({ label: name, detail: "helper" }),
  );
  allCompletions = allCompletions.concat(
    Object.keys(handlebarOptions.data).map((key) => ({
      label: `@${key}`,
      detail: "global variable",
    })),
  );

  const allAttributes = await index.queryPrefix(`attr:`);
  allCompletions = allCompletions.concat(
    compileAttributeCompletions(allAttributes),
  );

  return {
    from: completeEvent.pos - match[1].length,
    options: allCompletions,
  };
}