function canonicalKey(event) {
    let name = [];

    if (event.altKey) name.push('M')
    if (event.ctrlKey) name.push('C')
    if (event.metaKey) name.push('H')
    if (event.shiftKey) name.push('S')

    name.push(event.key)

    return name.join('-')
}

function handleKeyDown(editor, event) {
    if (event.repeating) return true;

    const key = canonicalKey(event)

    if (this.keys.hasOwnProperty(key)) {
        const action = this.keys[key]
        if (editor.hasOwnProperty(action)) {
            console.log('Key down ' + key + ', calling action ' + action)
            return editor[action](event)
        } else {
            console.warn('Unknown action on editor: ' + action)
        }
    } else {
        console.log('Key down ' + key)
    }

    return true
}

function mapKey(key, action) {
    if (this.keys.hasOwnProperty(key)) {
        console.warn(`Re-defining ${key} to call ${action}`)
    } else {
        console.log(`Defining ${key} to call ${action}`)
    }
    this.keys[key] = action
}

function Keymap() {
    return {
        keys: {},
        mapKey,
        handleKey: handleKeyDown
    }
}

export default Keymap