/*
Copyright (C) 2021 Yarmo Mackenbach

This program is free software: you can redistribute it and/or modify it under
the terms of the GNU Affero General Public License as published by the Free
Software Foundation, either version 3 of the License, or (at your option)
any later version.

This program is distributed in the hope that it will be useful, but WITHOUT
ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License for more
details.

You should have received a copy of the GNU Affero General Public License along
with this program. If not, see <https://www.gnu.org/licenses/>.

Also add information on how to contact you by electronic and paper mail.

If your software can interact with users remotely through a computer network,
you should also make sure that it provides a way for users to get its source.
For example, if your program is a web application, its interface could display
a "Source" link that leads users to an archive of the code. There are many
ways you could offer source, and different solutions will be better for different
programs; see section 13 for the specific requirements.

You should also get your employer (if you work as a programmer) or school,
if any, to sign a "copyright disclaimer" for the program, if necessary. For
more information on this, and how to apply and follow the GNU AGPL, see <https://www.gnu.org/licenses/>.
*/
import QRCode from 'qrcode'
import * as openpgp from 'openpgp'
import * as utils from './utils.js'

// Prepare element selectors
const elFormSignatureProfile = document.body.querySelector("#formGenerateSignatureProfile")
const elFormEncrypt = document.body.querySelector("#dialog--encryptMessage form")
const elFormVerify = document.body.querySelector("#dialog--verifySignature form")
const elFormSearch = document.body.querySelector("#search")

const elUtilWKD = document.body.querySelector("#form-util-wkd")
const elUtilQRFP = document.body.querySelector("#form-util-qrfp")
const elUtilQR = document.body.querySelector("#form-util-qr")
const elUtilProfileURL = document.body.querySelector("#form-util-profile-url")

const elUtilArgon2Generation = document.body.querySelector("#form-util-argon2-generate")
const elUtilArgon2Verification = document.body.querySelector("#form-util-argon2-verify")

const elUtilBcryptGeneration = document.body.querySelector("#form-util-bcrypt-generate")
const elUtilBcryptVerification = document.body.querySelector("#form-util-bcrypt-verify")

// Initialize UI elements and event listeners
export function init() {
    // Run context-dependent scripts
    if (elFormEncrypt) {
        runEncryptionForm()
    }

    if (elFormVerify) {
        runVerificationForm()
    }

    if (elFormSearch) {
        runSearchForm()
    }

    if (elUtilWKD) {
        runWKDUtility()
    }

    if (elUtilQRFP) {
        runQRFPUtility()
    }

    if (elUtilQR) {
        runQRUtility()  
    }

    if (elUtilProfileURL) {
        runProfileURLUtility()  
    }

    if (elUtilArgon2Generation) {
        runArgon2GenerationUtility()  
    }

    if (elUtilArgon2Verification) {
        runArgon2VerificationUtility()  
    }

    if (elUtilBcryptGeneration) {
        runBcryptGenerationUtility()  
    }

    if (elUtilBcryptVerification) {
        runBcryptVerificationUtility()  
    }
}

const runEncryptionForm = () => {
    elFormEncrypt.onsubmit = async function (evt) {
        evt.preventDefault();

        try {
            // Fetch a key if needed
            await utils.fetchProfileKey();

            // Encrypt the message
            let config = openpgp.config;
            config.show_comment = false;
            config.show_version = false;
            
            let encrypted = await openpgp.encrypt({
                message: await openpgp.createMessage({
                    text: elFormEncrypt.querySelector('.input').value
                }),
                encryptionKeys: window.kx.key.object,
                config: config
            });
            elFormEncrypt.querySelector('.output').value = encrypted;
        } catch (e) {
            console.error(e);
            elFormEncrypt.querySelector('.output').value = `Could not encrypt message!\n==========================\n${e.message ? e.message : e}`;
        }
    }
}

const runVerificationForm = () => {
    elFormVerify.onsubmit = async function (evt) {
        evt.preventDefault();

        try {
            // Fetch a key if needed
            await utils.fetchProfileKey();

            // Try two different methods of signature reading
            let signature = null, verified = null, readError = null;
            try {
                signature = await openpgp.readMessage({
                    armoredMessage: elFormVerify.querySelector('.input').value
                });
            } catch(e) {
                try {
                    signature = await openpgp.readCleartextMessage({
                        cleartextMessage: elFormVerify.querySelector('.input').value
                    });
                } catch(e) {
                    readError = e;
                }
            }
            if (signature == null) { throw(readError) };

            // Verify the signature
            verified = await openpgp.verify({
                message: signature,
                verificationKeys: window.kx.key.object
            });

            if (await verified.signatures[0].verified) {
                elFormVerify.querySelector('.output').value = `The message was signed by the profile's key.`;
            } else {
                elFormVerify.querySelector('.output').value = `The message was NOT signed by the profile's key.`;
            }
        } catch (e) {
            console.error(e);
            elFormVerify.querySelector('.output').value = `Could not verify signature!\n===========================\n${e.message ? e.message : e}`;
        }
    }
}

const runSearchForm = () => {
    elFormSearch.onsubmit = function (evt) {
        evt.preventDefault();

        const identifier = elFormSearch.querySelector("input[type='search']").value;
        window.location.href = `/${encodeURIComponent(identifier)}`;
    }

    elFormSearch.querySelectorAll("input[type='radio']").forEach(function (el) {
        el.oninput = function (evt) {
            evt.preventDefault();

            if (evt.target.getAttribute('id') === 'protocol-sig') {
                elFormSearch.querySelector("input[type='search']").setAttribute('disabled', true);
            } else {
                elFormSearch.querySelector("input[type='search']").removeAttribute('disabled');
            }
        }
    });
    
    elFormSearch.querySelector("input[type='radio']:checked").dispatchEvent(new Event('input'));
}

const runWKDUtility = () => {
    elUtilWKD.onsubmit = function (evt) {
        evt.preventDefault();
    }

    const elInput = document.body.querySelector("#input");
    const elOutput = document.body.querySelector("#output");
    const elOutputDirect = document.body.querySelector("#output_url_direct");
    const elOutputAdvanced = document.body.querySelector("#output_url_advanced");
    let match;

    elInput.addEventListener("input", async function(evt) {
        if (evt.target.value) {
            if (/(.*)@(.{1,}\..{1,})/.test(evt.target.value)) {
                match = evt.target.value.match(/(.*)@(.*)/);
                elOutput.innerText = await utils.computeWKDLocalPart(match[1]);
                elOutputDirect.innerText = `https://${match[2]}/.well-known/openpgpkey/hu/${elOutput.innerText}?l=${match[1]}`;
                elOutputAdvanced.innerText = `https://openpgpkey.${match[2]}/.well-known/openpgpkey/${match[2]}/hu/${elOutput.innerText}?l=${match[1]}`;
            } else {
                elOutput.innerText = await utils.computeWKDLocalPart(evt.target.value);
                elOutputDirect.innerText = "Waiting for input";
                elOutputAdvanced.innerText = "Waiting for input";
            }
        } else {
            elOutput.innerText = "Waiting for input";
            elOutputDirect.innerText = "Waiting for input";
            elOutputAdvanced.innerText = "Waiting for input";
        }
    });

    elInput.dispatchEvent(new Event("input"));
}

const runQRFPUtility = () => {
    elUtilQRFP.onsubmit = function (evt) {
        evt.preventDefault();
    }

    const qrTarget = document.getElementById('qrcode');
    const qrContext = qrTarget.getContext('2d');
    const qrOpts = {
        errorCorrectionLevel: 'H',
        margin: 1,
        width: 256,
        height: 256
    };

    const elInput = document.body.querySelector("#input");

    elInput.addEventListener("input", async function(evt) {
        if (evt.target.value) {
            QRCode.toCanvas(qrTarget, evt.target.value, qrOpts, function (error) {
                if (error) {
                    qrContext.clearRect(0, 0, qrTarget.width, qrTarget.height);
                    console.error(error);
                }
            });
        } else {
            qrContext.clearRect(0, 0, qrTarget.width, qrTarget.height);
        }
    });

    elInput.dispatchEvent(new Event("input"));
}

const runQRUtility = () => {
    elUtilQR.onsubmit = function (evt) {
        evt.preventDefault();
    }

    const qrTarget = document.getElementById('qrcode');
    const qrContext = qrTarget.getContext('2d');
    const qrOpts = {
        errorCorrectionLevel: 'L',
        margin: 1,
        width: 256,
        height: 256
    };

    const elInput = document.body.querySelector("#input");

    if (elInput.innerText) {
        elInput.innerText = decodeURIComponent(elInput.innerText);

        QRCode.toCanvas(qrTarget, elInput.innerText, qrOpts, function (error) {
            if (error) {
                document.body.querySelector("#qrcode--altLink").href = "#";
                qrContext.clearRect(0, 0, qrTarget.width, qrTarget.height);
                console.error(error);
            } else {
                document.body.querySelector("#qrcode--altLink").href = elInput.innerText;
            }
        });
    } else {
        qrContext.clearRect(0, 0, qrTarget.width, qrTarget.height);
    }
}

const runProfileURLUtility = () => {
    elUtilProfileURL.onsubmit = function (evt) {
        evt.preventDefault();
    }

    const elInput = document.body.querySelector("#input"),
        elSource = document.body.querySelector("#source"),
        elOutput = document.body.querySelector("#output");

    let data = {
        input: elInput.value,
        source: elSource.value
    };

    elInput.addEventListener("input", async function(evt) {
        data = {
            input: elInput.value,
            source: elSource.value
        };
        elOutput.innerText = await utils.generateProfileURL(data);
    });

    elSource.addEventListener("input", async function(evt) {
        data = {
            input: elInput.value,
            source: elSource.value
        };
        elOutput.innerText = await utils.generateProfileURL(data);
    });

    elInput.dispatchEvent(new Event("input"));
}

const runArgon2GenerationUtility = () => {
    elUtilArgon2Generation.onsubmit = function (evt) {
        evt.preventDefault();
    }

    const elInput = elUtilArgon2Generation.querySelector(".input"),
        elOutput = elUtilArgon2Generation.querySelector(".output"),
        elFeedback = elUtilArgon2Generation.querySelector(".feedback");

    elInput.addEventListener("input", async function(evt) {
        elOutput.innerText = await utils.generateArgon2Hash(elInput.value);

        if (elInput.value == "") {
            elFeedback.innerHTML = "";
        } else {
            let feedbackContent = "";
            if (!(/openpgp4fpr:[0-9a-zA-Z]+/.test(elInput.value))) {
                feedbackContent += "❗ Valid proofs must begin with <strong>openpgp4fpr:</strong>. <button class='inline' onclick='window.kx__fixArgon2Input();'>Fix now</button><br>";
            }
            if (!(elInput.value === elInput.value.toLowerCase())) {
                feedbackContent += "❗ Valid proofs must be lowercase. <button class='inline' onclick='window.kx__fixArgon2Input();'>Fix now</button><br>";
            }
            elFeedback.innerHTML = feedbackContent;
        }
    });

    elInput.dispatchEvent(new Event("input"));
}

const runArgon2VerificationUtility = () => {
    elUtilArgon2Verification.onsubmit = function (evt) {
        evt.preventDefault();
    }

    const elInput = elUtilArgon2Verification.querySelector(".input"),
        elHash = elUtilArgon2Verification.querySelector(".hash"),
        elOutput = elUtilArgon2Verification.querySelector(".output");

    const onInput = async function(evt) {
        if (elInput.value && elHash.value) {
            elOutput.innerText = await utils.verifyArgon2Hash(elInput.value, elHash.value)
                ? "✅ Hash matches the input"
                : "❌ Hash does not match the input";
        } else {
            elOutput.innerText = "Waiting for input…"
        }
    }

    elInput.addEventListener("input", onInput);
    elHash.addEventListener("input", onInput);

    elInput.dispatchEvent(new Event("input"));
}

window.kx__fixArgon2Input = () => {
    const elInput = document.querySelector('#form-util-argon2-generate .input');
    elInput.value = elInput.value.toLowerCase();

    if (!(/openpgp4fpr:[0-9a-zA-Z]+/.test(elInput.value))) {
        elInput.value = `openpgp4fpr:${elInput.value}`;
    }
    
    elInput.dispatchEvent(new Event("input"));
}

const runBcryptGenerationUtility = () => {
    elUtilBcryptGeneration.onsubmit = function (evt) {
        evt.preventDefault();
    }

    const elInput = elUtilBcryptGeneration.querySelector(".input"),
        elOutput = elUtilBcryptGeneration.querySelector(".output"),
        elFeedback = elUtilBcryptGeneration.querySelector(".feedback");

    elInput.addEventListener("input", async function(evt) {
        elOutput.innerText = await utils.generateBcryptHash(elInput.value);

        if (elInput.value == "") {
            elFeedback.innerHTML = "";
        } else {
            let feedbackContent = "";
            if (!(/openpgp4fpr:[0-9a-zA-Z]+/.test(elInput.value))) {
                feedbackContent += "❗ Valid proofs must begin with <strong>openpgp4fpr:</strong>. <button class='inline' onclick='window.kx__fixBcryptInput();'>Fix now</button><br>";
            }
            if (!(elInput.value === elInput.value.toLowerCase())) {
                feedbackContent += "❗ Valid proofs must be lowercase. <button class='inline' onclick='window.kx__fixBcryptInput();'>Fix now</button><br>";
            }
            elFeedback.innerHTML = feedbackContent;
        }
    });

    elInput.dispatchEvent(new Event("input"));
}

const runBcryptVerificationUtility = () => {
    elUtilBcryptVerification.onsubmit = function (evt) {
        evt.preventDefault();
    }

    const elInput = elUtilBcryptVerification.querySelector(".input"),
        elHash = elUtilBcryptVerification.querySelector(".hash"),
        elOutput = elUtilBcryptVerification.querySelector(".output");

    const onInput = async function(evt) {
        if (elInput.value && elHash.value) {
            elOutput.innerText = await utils.verifyBcryptHash(elInput.value, elHash.value)
                ? "✅ Hash matches the input"
                : "❌ Hash does not match the input";
        } else {
            elOutput.innerText = "Waiting for input…"
        }
    }

    elInput.addEventListener("input", onInput);
    elHash.addEventListener("input", onInput);

    elInput.dispatchEvent(new Event("input"));
}

window.kx__fixBcryptInput = () => {
    const elInput = document.querySelector('#form-util-bcrypt-generate .input');
    elInput.value = elInput.value.toLowerCase();

    if (!(/openpgp4fpr:[0-9a-zA-Z]+/.test(elInput.value))) {
        elInput.value = `openpgp4fpr:${elInput.value}`;
    }

    elInput.dispatchEvent(new Event("input"));
}