simple-deno-import-gitea/app.ts

import { Application, Router, isHttpError } from "https://deno.land/x/oak@v12.1.0/mod.ts";
import {
    searchRepositoryWithTopic,
    getRepositoryTags,
    getRepositoryContent
} from "./gitea.ts";
import { ContentsResponse } from "./gitea_api.d.ts";
import { Command } from "https://deno.land/x/cliffy@v0.25.7/mod.ts";

// import { load } from "https://deno.land/std@0.181.0/dotenv/mod.ts";
// const env = await load();

const app = new Application();
const router = new Router();

const RelativeTopic = "denolib";

export interface CompletionList {
    /** The list (or partial list) of completion items. */
    items: string[];
    /** If the list is a partial list, and further queries to the endpoint will
     * change the items, set `isIncomplete` to `true`. */
    isIncomplete?: boolean;
    /** If one of the items in the list should be preselected (the default
     * suggestion), then set the value of `preselect` to the value of the item. */
    preselect?: string;
}

router.get("/.well-known/deno-import-intellisense.json", (ctx) => {
    console.log("get /.well-known/deno-import-intellisense.json");
    ctx.response.type = "application/json";
    ctx.response.body = {
        "version": 2,
        "registries": [
            {
                "schema": "/:package([a-z0-9_]*@[a-z0-9_]*)/:version?/:path*",
                "variables": [
                    {
                        "key": "package",
                    //    "documentation": "/docs/packages/${package}",
                        "url": "/packages/${package}"
                    },
                    {
                        "key": "version",
                        "url": "/packages/${package}/versions"
                    },
                    {
                        "key": "path",
                    //    "documentation": "/docs/packages/${package}/${{version}}/paths/${path}",
                        "url": "/packages/${package}/${{version}}/paths/${path}"
                    }
                ]
            }
        ]
    };
});

router.get("/packages/:package", async (ctx) => {
    const packageName = ctx.params.package;
    console.log(`searchRepositoryWithTopic: ${packageName}`);
    const repositories = await searchRepositoryWithTopic(RelativeTopic);
    const repo_name = repositories.data?.map((repo) => repo.full_name)
        .filter(x => x !== undefined)
        .map(x=> x?.replace("/","@")) ?? [];
    const completionList: CompletionList = {
        items: repo_name as string[],
        isIncomplete: true, // TODO: check if there are more than max results
        preselect: repo_name[0]
    };
    ctx.response.type = "application/json";
    ctx.response.body = completionList;
});

router.get("/packages/:package/versions", async (ctx) => {
    const packageName = ctx.params.package;
    const [owner, repo] = packageName.split("@");
    console.log(`getTags: owner: ${owner}, repo: ${repo}`);
    const tags = await getRepositoryTags(owner, repo);
    const candidate = ["main", ...tags.map((tag) => tag.name) as string[]]
    const completionList: CompletionList = {
        items: candidate,
        isIncomplete: false,
        preselect: candidate[0]
    };
    ctx.response.type = "application/json";
    ctx.response.body = completionList;
});

router.get("/packages/:package/:version/paths/:path*", async (ctx) => {
    const packageName = ctx.params.package;
    const version = ctx.params.version;
    const path = ctx.params.path;
    const [owner, repo] = packageName.split("@");
    console.log(`getFilesEntry: owner: ${owner}, repo: ${repo}, path: ${path}, version: ${version}`);
    const entries = await getRepositoryContent(owner, repo, path ?? "", version) as ContentsResponse[];
    const completionList: CompletionList = {
        items: entries.map((entry) => entry.name) as string[],
        isIncomplete: false,
        preselect: entries[0].name
    };
    ctx.response.type = "application/json";
    ctx.response.body = completionList;
});

router.get("/:package([a-z0-9_]*@[a-z0-9_]*)/:version?/:path*", async (ctx) => {
    const packageName = ctx.params.package;
    const [owner, repo] = packageName.split("@");
    const version = ctx.params.version;
    const path = ctx.params.path;
    console.log(`getFiles: owner: ${owner}, repo: ${repo}, path: ${path}, version: ${version}`);
    const entries = await getRepositoryContent(owner, repo, path ?? "", version);
    if (entries instanceof Array) {
        ctx.response.type = "application/json";
        ctx.response.body = entries;
    }
    else {
        if ("errors" in entries){
            ctx.throw(404);
        }
        // TODO: check if the file is text file or not (e.g. image)
        ctx.response.type = "text/plain";
        ctx.response.body = atob(entries.content ?? "");
    }
});

app.use(router.routes());
app.use(router.allowedMethods());

app.use(async (ctx, next) => {
    try{
        await next();
    }
    catch (err) {
        console.log(err);
        if (isHttpError(err)) {
            ctx.response.status = err.status;
            const { message, status, stack } = err;
            ctx.response.body = { message, status, stack };
        }
        else {                                                                                                   throw err;
        }
    }
});



//app.use(async (ctx, next) => {
//    ctx.throw(404);
//    //ctx.response.body = "Not Found";
//    //await next();
//});
app.addEventListener("listen", ({ hostname, port, secure }) => {
    console.log(`🚀 Listening on: ${secure ? "https://" : "http://"}${hostname ?? "localhost"}:${port}`);
});

if (import.meta.main) {
    const cmd = new Command()
        .version("0.1.0")
        .description("Simple Deno import intellisense proxy server for Gitea")
        .option("-p, --port <port:number>", "Port number to listen on", { default: 9999 })
        .action(async ({ port }) => {
            await app.listen({ port: port });
        });
    await cmd.parse(Deno.args);
}