import { ipcMain, dialog, app } from 'electron'
import fs from 'fs'
import path from 'path'
import { encrypt, fromEncryptedJson } from './utils/keystore'
import logger from './logger'

const neptuneNative = require('@neptune/native')

const WALLETS_DIR = path.resolve(app.getPath('userData'), 'wallets')
fs.mkdirSync(WALLETS_DIR, { recursive: true })

function assertBasename(name: string) {
    if (!name || name !== path.basename(name)) {
        throw new Error('Invalid file name')
    }
}

function safeResolvePath(fileName: string) {
    assertBasename(fileName)
    const candidate = path.join(WALLETS_DIR, fileName)
    const realBase = fs.realpathSync(WALLETS_DIR)
    const realCandidate = fs.existsSync(candidate) ? fs.realpathSync(candidate) : candidate
    if (!(realCandidate === realBase || realCandidate.startsWith(realBase + path.sep))) {
        throw new Error('Access denied')
    }
    return realCandidate
}

ipcMain.handle('wallet:createKeystore', async (_event, seed, password) => {
    try {
        const keystore = await encrypt(seed, password)
        const timestamp = Date.now()
        const fileName = `neptune-wallet-${timestamp}.json`
        const filePath = path.join(WALLETS_DIR, fileName)
        fs.writeFileSync(filePath, keystore, 'utf-8')
        return { success: true, fileName }
    } catch (error: any) {
        logger.error('Error creating keystore:', error.message)
        throw error
    }
})

ipcMain.handle('wallet:saveKeystoreAs', async (_event, fileName: string) => {
    try {
        const pathToFileName = safeResolvePath(fileName)
        const keystore = fs.readFileSync(pathToFileName, 'utf-8')
        const timestamp = Date.now()
        const defaultName = `neptune-wallet-${timestamp}.json`
        const { canceled, filePath } = await dialog.showSaveDialog({
            title: 'Save Keystore File',
            defaultPath: path.join(app.getPath('documents'), defaultName),
            filters: [{ name: 'JSON', extensions: ['json'] }],
        })

        if (canceled || !filePath) return { success: false, filePath: null }
        if (path.extname(filePath).toLowerCase() !== '.json') {
            throw new Error('Invalid file extension. Please save as a .json file.')
        }

        fs.mkdirSync(path.dirname(filePath), { recursive: true })
        fs.writeFileSync(filePath, keystore, 'utf-8')
        return { success: true, filePath }
    } catch (error: any) {
        logger.error('Error saving keystore (Save As):', error.message)
        throw error
    }
})

ipcMain.handle('wallet:decryptKeystore', async (_event, fileName: string, password: string) => {
    try {
        const filePath = safeResolvePath(fileName)
        const json = fs.readFileSync(filePath, 'utf-8')
        const phrase = await fromEncryptedJson(json, password)
        return { phrase }
    } catch (error: any) {
        logger.error('Error decrypting keystore ipc:', error.message)
        throw error
    }
})

ipcMain.handle('wallet:checkKeystore', async () => {
    try {
        if (!fs.existsSync(WALLETS_DIR)) return { exists: false, fileName: null }
        const newestFile = fs
            .readdirSync(WALLETS_DIR)
            .filter((f) => f.endsWith('.json'))
            .sort(
                (a, b) =>
                    fs.statSync(path.join(WALLETS_DIR, b)).mtime.getTime() -
                    fs.statSync(path.join(WALLETS_DIR, a)).mtime.getTime()
            )[0]

        if (!newestFile) return { exists: false, fileName: null }
        const resolvedPath = safeResolvePath(newestFile)
        let minBlockHeight: number | null = null
        try {
            const json = fs.readFileSync(resolvedPath, 'utf-8')
            const data = JSON.parse(json)
            const height = data?.minBlockHeight
            if (Number.isFinite(height)) minBlockHeight = height
        } catch (error: any) {
            logger.warn('Unable to read minBlockHeight from keystore:', error.message)
        }
        return { exists: true, fileName: newestFile, minBlockHeight }
    } catch (error: any) {
        logger.error('Error checking keystore ipc:', error.message)
        return { exists: false, fileName: null, minBlockHeight: null, error: error.message }
    }
})

ipcMain.handle(
    'wallet:updateMinBlockHeight',
    async (_event, fileName: string | null, minBlockHeight: number | null) => {
        if (!fileName) {
            return { success: false, error: 'No keystore file name provided.' }
        }
        try {
            const filePath = safeResolvePath(fileName)
            if (!fs.existsSync(filePath)) {
                return { success: false, error: 'Keystore file not found.' }
            }
            const fileContents = fs.readFileSync(filePath, 'utf-8')
            const walletJson = JSON.parse(fileContents)
            walletJson.minBlockHeight = Number.isFinite(minBlockHeight) ? minBlockHeight : null
            fs.writeFileSync(filePath, JSON.stringify(walletJson, null, 2), 'utf-8')
            return { success: true, minBlockHeight }
        } catch (error: any) {
            logger.error('Error updating min block height:', error.message)
            return { success: false, error: error.message }
        }
    }
)

ipcMain.handle('wallet:getMinBlockHeight', async (_event, fileName: string | null) => {
    if (!fileName) {
        return { success: false, error: 'No keystore file name provided.', minBlockHeight: null }
    }
    try {
        const filePath = safeResolvePath(fileName)
        if (!fs.existsSync(filePath)) {
            return { success: false, error: 'Keystore file not found.', minBlockHeight: null }
        }
        const fileContents = fs.readFileSync(filePath, 'utf-8')
        const walletJson = JSON.parse(fileContents)
        const height = walletJson?.minBlockHeight
        return {
            success: true,
            minBlockHeight: Number.isFinite(height) ? height : null,
        }
    } catch (error: any) {
        logger.error('Error reading min block height:', error.message)
        return { success: false, error: error.message, minBlockHeight: null }
    }
})

ipcMain.handle('wallet:generateKeysFromSeed', async (_event, seedPhrase: string[]) => {
    try {
        const wallet = new neptuneNative.WalletManager()
        return JSON.parse(wallet.generateKeysFromSeed(seedPhrase))
    } catch (error: any) {
        logger.error('Error generating keys from seed ipc:', error.message)
        throw error
    }
})

ipcMain.handle('wallet:buildTransaction', async (_event, args) => {
    const { spendingKeyHex, inputAdditionRecords, outputAddresses, outputAmounts, fee } = args
    try {
        if (typeof spendingKeyHex !== 'string' || !/^(0x)?[0-9a-fA-F]+$/.test(spendingKeyHex)) {
            throw new Error('Invalid spending key')
        }

        if (
            !Array.isArray(inputAdditionRecords) ||
            !inputAdditionRecords.every((r) => typeof r === 'string')
        ) {
            throw new Error('Invalid inputAdditionRecords')
        }

        if (
            !Array.isArray(outputAddresses) ||
            !outputAddresses.every((a) => typeof a === 'string')
        ) {
            throw new Error('Invalid outputAddresses')
        }

        if (
            !Array.isArray(outputAmounts) ||
            !outputAmounts.every((a) => typeof a === 'string' && /^\d+(\.\d+)?$/.test(a))
        ) {
            throw new Error('Invalid outputAmounts')
        }

        if (typeof fee !== 'string' || !/^\d+(\.\d+)?$/.test(fee)) {
            throw new Error('Invalid fee')
        }

        const builder = new neptuneNative.SimpleTransactionBuilder()
        const result = await builder.buildTransaction(
            import.meta.env.VITE_APP_API,
            spendingKeyHex,
            inputAdditionRecords,
            typeof args?.minBlockHeight === 'number' && Number.isFinite(args.minBlockHeight)
                ? args.minBlockHeight
                : 0,
            outputAddresses,
            outputAmounts,
            fee
        )
        return JSON.parse(result)
    } catch (error: any) {
        logger.error('Error building transaction ipc:', error.message)
        throw error
    }
})

ipcMain.on('log:info', (_, ...msg: string[]) => logger.info(...msg))
ipcMain.on('log:warn', (_, ...msg: string[]) => logger.warn(...msg))
ipcMain.on('log:error', (_, ...msg: string[]) => logger.error(...msg))