import { vOnComplete, vResultValidator } from "@convex-dev/workpool";
import { assert } from "convex-helpers";
import { FunctionHandle } from "convex/server";
import { v } from "convex/values";
import { Id } from "./_generated/dataModel.js";
import { mutation, MutationCtx, query, QueryCtx } from "./_generated/server.js";
import { createLogger, Logger, logLevel } from "./logging.js";
import { getWorkflow } from "./model.js";
import { getWorkpool } from "./pool.js";
import { journalDocument, JournalEntry, workflowDocument } from "./schema.js";
import { getDefaultLogger } from "./utils.js";
import { WorkflowId, OnCompleteArgs } from "../types.js";

export const create = mutation({
  args: {
    workflowName: v.string(),
    workflowHandle: v.string(),
    workflowArgs: v.any(),
    maxParallelism: v.optional(v.number()),
    onComplete: v.optional(vOnComplete),
    // TODO: ttl
  },
  returns: v.string(),
  handler: async (ctx, args) => {
    const now = Date.now();
    const console = await getDefaultLogger(ctx);
    await updateMaxParallelism(ctx, console, args.maxParallelism);
    const workflowId = await ctx.db.insert("workflows", {
      name: args.workflowName,
      workflowHandle: args.workflowHandle,
      args: args.workflowArgs,
      generationNumber: 0,
      onComplete: args.onComplete,
    });
    console.debug(
      `Created workflow ${workflowId}:`,
      args.workflowArgs,
      args.workflowHandle,
    );
    // If we can't start it, may as well not create it, eh? Fail fast...
    await ctx.runMutation(args.workflowHandle as FunctionHandle<"mutation">, {
      workflowId,
      generationNumber: 0,
    });
    return workflowId as string;
  },
});

export const getStatus = query({
  args: {
    workflowId: v.id("workflows"),
  },
  returns: v.object({
    workflow: workflowDocument,
    inProgress: v.array(journalDocument),
    logLevel: logLevel,
  }),
  handler: getStatusHandler,
});

export async function getStatusHandler(
  ctx: QueryCtx,
  args: { workflowId: Id<"workflows"> },
) {
  const workflow = await ctx.db.get(args.workflowId);
  assert(workflow, `Workflow not found: ${args.workflowId}`);
  const console = await getDefaultLogger(ctx);

  const result: JournalEntry[] = [];
  const inProgressEntries = await ctx.db
    .query("steps")
    .withIndex("inProgress", (q) =>
      q.eq("step.inProgress", true).eq("workflowId", args.workflowId),
    )
    .collect();
  result.push(...inProgressEntries);
  console.debug(`${args.workflowId} blocked by`, result);
  return { workflow, inProgress: result, logLevel: console.logLevel };
}

export const cancel = mutation({
  args: {
    workflowId: v.id("workflows"),
  },
  returns: v.null(),
  handler: async (ctx, { workflowId }) => {
    const { workflow, inProgress, logLevel } = await getStatusHandler(ctx, {
      workflowId,
    });
    const console = createLogger(logLevel);
    if (inProgress.length > 0) {
      const workpool = await getWorkpool(ctx, {});
      for (const step of inProgress) {
        if (step.step.workId) {
          await workpool.cancel(ctx, step.step.workId);
        }
      }
    }
    assert(workflow.runResult === undefined, `Not running: ${workflowId}`);
    workflow.runResult = { kind: "canceled" };
    workflow.generationNumber += 1;
    console.debug(`Canceled workflow ${workflowId}:`, workflow);
    // TODO: Call onComplete hook
    // TODO: delete everything unless ttl is set
    await ctx.db.replace(workflow._id, workflow);
  },
});

export const complete = mutation({
  args: {
    workflowId: v.id("workflows"),
    generationNumber: v.number(),
    runResult: vResultValidator,
    now: v.number(),
  },
  returns: v.null(),
  handler: async (ctx, args) => {
    const workflow = await getWorkflow(
      ctx,
      args.workflowId,
      args.generationNumber,
    );
    const console = await getDefaultLogger(ctx);
    if (workflow.runResult) {
      throw new Error(`Workflow not running: ${workflow}`);
    }
    workflow.runResult = args.runResult;
    console.event("completed", {
      workflowId: workflow._id,
      name: workflow.name,
      status: workflow.runResult.kind,
      overallDurationMs: Date.now() - workflow._creationTime,
    });
    if (workflow.onComplete) {
      await ctx.runMutation(
        workflow.onComplete.fnHandle as FunctionHandle<
          "mutation",
          OnCompleteArgs
        >,
        {
          workflowId: workflow._id as unknown as WorkflowId,
          result: workflow.runResult,
          context: workflow.onComplete.context,
        },
      );
    }
    // TODO: delete everything unless ttl is set
    console.debug(`Completed workflow ${workflow._id}:`, workflow);
    await ctx.db.replace(workflow._id, workflow);
  },
});

export const cleanup = mutation({
  args: {
    workflowId: v.string(),
  },
  returns: v.boolean(),
  handler: async (ctx, args) => {
    const workflowId = ctx.db.normalizeId("workflows", args.workflowId);
    if (!workflowId) {
      throw new Error(`Invalid workflow ID: ${args.workflowId}`);
    }
    const workflow = await ctx.db.get(workflowId);
    if (!workflow) {
      return false;
    }
    const logger = await getDefaultLogger(ctx);
    if (workflow.runResult?.kind !== "success") {
      logger.debug(
        `Can't clean up workflow ${workflowId} since it hasn't completed.`,
      );
      return false;
    }
    logger.debug(`Cleaning up workflow ${workflowId}`, workflow);
    await ctx.db.delete(workflowId);
    const journalEntries = await ctx.db
      .query("steps")
      .withIndex("workflow", (q) => q.eq("workflowId", workflowId))
      .collect();
    for (const journalEntry of journalEntries) {
      logger.debug("Deleting journal entry", journalEntry);
      await ctx.db.delete(journalEntry._id);
    }
    return true;
  },
});

async function updateMaxParallelism(
  ctx: MutationCtx,
  console: Logger,
  maxParallelism: number | undefined,
) {
  const config = await ctx.db.query("config").first();
  if (config) {
    if (maxParallelism && maxParallelism !== config.maxParallelism) {
      console.warn("Updating max parallelism to", maxParallelism);
      await ctx.db.patch(config._id, { maxParallelism });
    }
  } else {
    await ctx.db.insert("config", { maxParallelism });
  }
}

// eslint-disable-next-line @typescript-eslint/no-unused-vars
const console = "THIS IS A REMINDER TO USE getDefaultLogger";