main.js

// This script will be run within the webview itself
// It cannot access the main VS Code APIs directly.
(function () {
    const vscode = acquireVsCodeApi();


    console.log("Started");
    /**
     * @type {HTMLSelectElement}
     */
    const toolDropDown = document.getElementById("tools");
    toolDropDown.addEventListener('change', event => {
        vscode.postMessage({ type: "toolSelected", toolName: toolDropDown.options[toolDropDown.selectedIndex].value });
    });

    // Handle messages sent from the extension to the webview
    window.addEventListener('message', event => {
        const message = event.data; // The json data that the extension sent
        console.log("Received message");
        switch (message.type) {
            case 'updateConstants':
                {
                    updateConstants(message.constants, message.uri);
                    break;
                }
            case 'updateOptions':
                {
                    updateOptions(message.options);
                    break;
                }
            case 'fillTools':
                {
                    fillTools(message.tools);
                    break;
                }
        }
    });


    function fillTools(tools) {
        const select = document.querySelector("#tools");
        select.innerHTML = "";

        for (const tool of tools) {
            const option = document.createElement("option");
            option.value = tool;
            option.text = tool;
            select.appendChild(option);
        }

        const oldState = vscode.getState() || { tools: [], constants: [], options: [] };
        vscode.setState({ tools: tools, constants: oldState.constants, options: oldState.options });
    }

    function addConstantItem(ul, name, value) {
        const li = document.createElement("li");

        const nameBox = document.createElement("label");
        nameBox.id = "name-" + name;
        nameBox.appendChild(document.createTextNode(name));
        nameBox.classList.add("name");

        li.appendChild(nameBox);

        const valueBox = document.createElement("input");
        valueBox.id = "value-" + name;
        valueBox.type = "text";
        valueBox.value = value;
        valueBox.classList.add("value");
        valueBox.addEventListener("input", event => {
            let oldState = vscode.getState();
            for (const file of oldState.constants) {
                if (file.uri === oldState.currentUri) {
                    for (const constant of file.constants) {
                        if (constant.name === name) {
                            constant.value = valueBox.value;
                            break;
                        }
                    }
                    break;
                }
            }
            vscode.setState({ tools: oldState.tools, constants: oldState.constants, options: oldState.options, currentUri: oldState.currentUri });
        });

        li.appendChild(valueBox);

        ul.appendChild(li);
    }

    function addOptionItem(ul, name, value) {
        const li = document.createElement("li");

        const nameBox = document.createElement("input");
        nameBox.id = "name-" + name;
        nameBox.type = "text";
        nameBox.value = name;
        nameBox.classList.add("name");

        li.appendChild(nameBox);

        const valueBox = document.createElement("input");
        valueBox.id = "value-" + name;
        valueBox.type = "text";
        valueBox.value = value;
        valueBox.classList.add("value");

        li.appendChild(valueBox);

        ul.appendChild(li);
    }

    /**
     *
     * @param {Array<{ uri: string, constants: Array<{ name: string, value: string }> }>} constants
     * @param {string} uri
     */
    function updateConstants(constants, uri) {
        const constantsUl = document.querySelector("#constants");
        const oldState = vscode.getState();

        for (const file of constants) {
            for (const constant of file.constants) {
                const index = oldState.constants.findIndex(x => x.uri === file.uri);
                if (index !== -1) {
                    const oldConstantIndex = oldState.constants[index].constants.findIndex(x => x.name === constant.name);
                    if (oldConstantIndex !== -1) {
                        constant.value = oldState.constants[index].constants[oldConstantIndex].value;
                    }
                }
            }
        }

        constantsUl.innerHTML = "";
        for (const file of constants) {
            if (file.uri === uri) {
                for (const constant of file.constants) {
                    addConstantItem(constantsUl, constant.name, constant.value);
                }
                break;
            }
        }

        vscode.setState({ tools: oldState.tools, constants: constants, options: oldState.options, currentUri: uri });
    }

    /**
     * @param {Array<{name: string, value: string}>} options
     */
    function updateOptions(options) {
        const optionsUl = document.querySelector("#options");
        optionsUl.innerHTML = "";
        for (const option of options) {
            addOptionItem(optionsUl, option.name, option.value);
        }

        const oldState = vscode.getState();
        vscode.setState({ tools: oldState.tools, constants: oldState.constants, options: options, currentUri: oldState.currentUri });
    }

    const oldState = vscode.getState() || { tools: [], constants: [], options: [], currentUri: "" };

    const tools = oldState.tools;
    const constants = oldState.constants;
    const options = oldState.options;
    const currentUri = oldState.currentUri;

    if (oldState.tools.length === 0) {
        vscode.postMessage({ type: "init" });
    } else {
        fillTools(tools);
        updateOptions(options);
        updateConstants(constants, currentUri);
    }
}());