import { CONVERT_URL } from './config.js'

function readFileAsBase64(file) {
    return new Promise((resolve, reject) => {
        const reader = new FileReader()
        reader.onload = () => {
            const dataUrl = typeof reader.result === 'string' ? reader.result : ''
            const splitIndex = dataUrl.indexOf(',')
            if (splitIndex === -1) {
                reject(new Error('Invalid file data'))
                return
            }
            resolve(dataUrl.slice(splitIndex + 1))
        }
        reader.onerror = () => reject(reader.error || new Error('Failed to read file'))
        reader.readAsDataURL(file)
    })
}

export async function convertFileToMarkdown(file) {
    const base64 = await readFileAsBase64(file)
    const res = await fetch(CONVERT_URL, {
        method: 'POST',
        headers: {
            'Content-Type': 'application/json',
        },
        body: JSON.stringify({
            file: base64,
            filename: file.name || 'document',
        }),
    })

    if (!res.ok) {
        const errorText = await res.text()
        throw new Error(`HTTP ${res.status}: ${errorText}`)
    }

    const data = await res.json()
    if (!data || typeof data.markdown !== 'string') {
        throw new Error('No markdown returned')
    }
    return data.markdown
}