cna.nim

import strutils
import system
import std/httpclient
import strformat
import std/xmltree
from htmlparser import parseHtml
import nimquery
import sugar
import sequtils
import unpack
import std/parseopt
import std/tables

const tbl = {
    "latest": "https://www.channelnewsasia.com/api/v1/rss-outbound-feed?_format=xml", 
    "asia": "https://www.channelnewsasia.com/api/v1/rss-outbound-feed?_format=xml&category=6511",
    "business": "https://www.channelnewsasia.com/api/v1/rss-outbound-feed?_format=xml&category=6936",
    "singapore": "https://www.channelnewsasia.com/api/v1/rss-outbound-feed?_format=xml&category=10416", 
    "sport": "https://www.channelnewsasia.com/api/v1/rss-outbound-feed?_format=xml&category=10296", 
    "world": "https://www.channelnewsasia.com/api/v1/rss-outbound-feed?_format=xml&category=6311"
}.toOrderedTable

let keys: seq[string] = tbl.keys.toSeq.map((k) => fmt"<{k}>")
var 
    p = initOptParser()

proc getFeed(key: string): void
proc genUsageText(isErr: bool): string

while true:
  p.next()
  case p.kind
  of cmdEnd:
    quit(genUsageText(isErr = false), 0)
  of cmdShortOption, cmdLongOption: break
  of cmdArgument:
    if tbl.hasKey(p.key):
        getFeed(p.key)
        quit(0)
    else:
        quit(genUsageText(isErr = true), 0)

proc getFeed(key: string): void =
    let client = newHttpClient()
    let response = client.request(tbl[key], httpMethod = HttpGet)
    let xml = parseHtml(response.body)
    echo fmt"## {key} News".toUpper() & "\n"
    for item in xml.querySelectorAll("item"):
        let item = item.innerText.strip().split("\n").map((s) => s.strip())
        item.unpackSeq(title, link)
        echo &"{title}\n{link}\n"

proc genUsageText(isErr: bool): string =
    let keysStr = keys.join(" ")
    let usageStr = fmt"Usage: $ cna {keysStr}"
    if isErr:
        return fmt"""
Error: invalid category
{usageStr}"""
    return fmt"""{usageStr}"""