class PackageIndexEntry {
    name: string
    description: string | null
    website: string | null
    version: string | null
    report: string | null
}
function toHTML(entry: PackageIndexEntry): HTMLTableRowElement {
    let v = entry.version != null ? `<span>${escapeHtml(entry.version)}</span>` : ""
    let d = entry.description != null ? `<p>${escapeHtml(entry.description)}</p>` : ""
    let w = entry.website != null ? `<a href="${encodeURI(entry.website)}">Website</a>` : ""
    let r = entry.report != null ? `<a href="${encodeURI(entry.report)}">Log</a>` : ""
    let row = <HTMLTableRowElement>(document.createElement('tr'))
    row.innerHTML = `<td>
            <h2>${escapeHtml(entry.name)} ${v}</h2>
            ${d}
            ${w}
            ${r}
        </td>`
    return row
}

const API_VERSION = 1
const ENDPOINT = `/api/v${API_VERSION}`
class InfoPayload {
    count: number
    hakurei_version: string
}

async function infoRequest(): Promise<InfoPayload> {
    const res = await fetch(`${ENDPOINT}/info`)
    const res_1 = await res.json()
    return res_1 as InfoPayload
}
class GetPayload {
    count: number
    values: PackageIndexEntry[]
}

enum SortOrders {
    DeclarationAscending = 0,
    DeclarationDescending,
    NameAscending,
    NameDescending
}
async function getRequest(limit: number, index: number, sort: SortOrders): Promise<GetPayload> {
    const res = await fetch(`${ENDPOINT}/get?limit=${limit}&index=${index}&sort=${sort.valueOf()}`)
    const res_1 = await res.json()
    return res_1 as GetPayload
}
class State {
    entriesPerPage: number = 10
    currentPage: number = 1
    entryIndex: number = 0
    maxEntries: number = 0
    getEntriesPerPage(): number {
        return this.entriesPerPage
    }
    setEntriesPerPage(entriesPerPage: number) {
        this.entriesPerPage = entriesPerPage
        if (this.currentPage > this.getMaxPage()) {
            this.setCurrentPage(this.getMaxPage())
        }
    }
    getCurrentPage(): number {
        return this.currentPage
    }
    setCurrentPage(page: number) {
        this.currentPage = page
        this.setEntryIndex((this.getCurrentPage() - 1) * this.getEntriesPerPage())
        document.getElementById("page-number").innerText = String(this.getCurrentPage())
    }
    getEntryIndex(): number {
        return this.entryIndex
    }
    setEntryIndex(entryIndex: number) {
        this.entryIndex = entryIndex
        this.updateRange()
        this.updateListings()
    }
    getMaxEntries(): number {
        return this.maxEntries
    }
    setMaxEntries(max: number) {
        this.maxEntries = max
    }
    getMaxPage(): number {
        return Math.ceil(this.getMaxEntries() / this.getEntriesPerPage())
    }
    updateRange() {
        let max = Math.min(this.getEntryIndex() + this.getEntriesPerPage(), this.getMaxEntries())
        document.getElementById("entry-counter").innerText = `${this.getEntryIndex() + 1}-${max} of ${this.getMaxEntries()}`
    }
    updateListings() {
        getRequest(this.getEntriesPerPage(), this.entryIndex, 0)
            .then(res => {
                let table = document.getElementById("pkg-list")
                table.innerHTML = ''
                for(let i = 0; i < res.count; i++) {
                    table.appendChild(toHTML(res.values[i]))
                }
            })
    }

}

let STATE: State

function prevPage() {
    let current = STATE.getCurrentPage()
    if (current > 1) {
        STATE.setCurrentPage(STATE.getCurrentPage() - 1)
    }
}
function nextPage() {
    let current = STATE.getCurrentPage()
    if (current < STATE.getMaxPage()) {
        STATE.setCurrentPage(STATE.getCurrentPage() + 1)
    }
}

function escapeHtml(str: string): string {
    return str
        .replace(/&/g, '&amp;')
        .replace(/</g, '&lt;')
        .replace(/>/g, '&gt;')
        .replace(/"/g, '&quot;')
        .replace(/'/g, '&apos;')
}

document.addEventListener("DOMContentLoaded", () => {
    STATE = new State()
    infoRequest()
        .then(res => {
            STATE.setMaxEntries(res.count)
            document.getElementById("hakurei-version").innerText = res.hakurei_version
            STATE.updateRange()
            STATE.updateListings()
        })

    document.getElementById("count").addEventListener("change", (event) => {
        STATE.setEntriesPerPage(parseInt((event.target as HTMLSelectElement).value))
    })
})