import type { Diary, Project } from "../content/types";
import type { Command, Flag } from "./types";
import Color from "color";

function getCommandByName(name: string): Command | undefined {
    return commandList.find(cmd => cmd.name === name);
}

function illegalUse(raw: string, cmd: Command): string[] {
    return [
        "Syntax error!",
        `Cannot parse "${raw}"`,
        ""
    ].concat(printSyntax(cmd));
}

function checkFlags(flags: string[], cmd: Command): boolean {
    if (!flags || flags === []) return true;
    if (!cmd.flags) return false;

    for (const flag of flags) {
        const isLong = flag.substring(0, 2) === "--";
        const flagObj = Object.values(cmd.flags).find(f => isLong ? f.long === flag.substring(2) : f.short === flag.substring(1));
        if (!flagObj) return false;
    }
    return true;
}

function checkSubcmd(subcmds: string[], cmd: Command): boolean {
    if (!subcmds || subcmds === []) return true;
    if (!cmd.subcommands) return false;

    for (const sc of subcmds) {
        const flagObj = Object.values(cmd.subcommands).find(s => s.name === sc);
        if (!flagObj) return false;
    }
    return true;
}

function checkFlagInclude(flagsProvided: string[], flag: Flag): boolean {
    if (!flag) return false;
    return flagsProvided.includes(`-${flag.short}`) || flagsProvided.includes(`--${flag.long}`);
}

export function printSyntax(cmd: Command): string[] {
    let flagsOption = "";
    let flagsDesc = [];
    if (cmd.flags && Object.keys(cmd.flags).length > 0) {
        flagsOption = " [";
        flagsDesc.push("");
        flagsDesc.push("Flags:");
        Object.values(cmd.flags).forEach((flag => {
            flagsOption += `-${flag.short} `;
            flagsDesc.push(`\t-${flag.short}\t--${flag.long}\t${flag.desc}`);
        }));
        flagsOption = flagsOption.substring(0, flagsOption.length - 1) + "]";
    }

    let subcmdOption = "";
    let subcmdDesc = [];
    if (cmd.subcommands && Object.keys(cmd.subcommands).length > 0) {
        subcmdOption = " [";
        subcmdDesc.push("");
        subcmdDesc.push("Arguments:");
        Object.values(cmd.subcommands).forEach((subcmd => {
            subcmdOption += `${subcmd.name}|`;
            subcmdDesc.push(`\t${subcmd.name}\t${subcmd.desc}`);
        }));
        subcmdOption = subcmdOption.substring(0, subcmdOption.length - 1) + "]";
    }

    return [`Usage: ${cmd.name}${flagsOption}${subcmdOption}`].concat(flagsDesc).concat(subcmdDesc);
}

const about: Command = {
    name: "about",
    desc: "Show information about this page.",
    execute: () => {
        return [
            "Hello there wanderer.",
            "So you want to know what this is about?",
            "",
            "Well, the answer is pretty unspectecular:",
            "This site presents some stuff that me, a human created.",
            "If you look arround you can read about my various projects.",
            "",
            "The navigation is done via this console interface.",
            "Even when you open a project page you don't need your mouse - just press Esc to close it.",
            "",
            "I hope you enjoy your stay here!",
            "If you want to know more about the creation of this page, type %{project this}.",
            "",
            "If you are kind of lost what to do, type %{help --this}."
        ];
    }
};

const help: Command = {
    name: "help",
    desc: "Shows helptext.",
    flags: { more: { long: "this", short: "t", desc: "Show information about this site." } },
    execute: (flags) => {
        if (help.flags && checkFlagInclude(flags, help.flags.more)) {
            return [
                "Hello user!",
                "What you see here should resemble a CLI. If you ever used Linux this should be pretty easy for you.",
                "",
                "Everyone else: Have no fear. It is pretty simple.", 
                "You just type in commands and the output is shown here or it does something on the webite.",
                "To find out, which commands are available, you can type %{help}.",
                "",
                "When wanting to know how to use a command, type %{man <command>} or %{<command> --help}.",
                "",
                "Have fun!"
            ];
        } else {
            const available = ["Available commands:"];
            commandList.filter(cmd => !cmd.hidden).forEach(cmd => available.push(`\t${cmd.name}\t${cmd.desc}`));
            available.push("");
            available.push("Need help about the general usage? Type %{help --this}!");
            return available;
        }
    }
};

const man: Command = {
    name: "man",
    desc: "Provides a manual for a command.",
    subcommands: {
        command: { name: "command", desc: "Name of a command" }
    },
    execute: (_flags, args) => {
        if (args.length !== 1) {
            return printSyntax(man);
        } else {
            const cmd = getCommandByName(args[0]);
            if (!cmd) return [`Cannot find command '${args[0]}'.`];
            else return printSyntax(cmd);
        }
    }
};

const project: Command = {
    name: "project",
    desc: "Show information about a project.",
    flags: {
        minimal: { short: "m", long: "minimal", desc: "Only show minimal information." },
        source: { short: "s", long: "source", desc: "Open git repository of project." },
        list: { short: "l", long: "list", desc: "\tShow list of projects." }
    },
    subcommands: { name: { name: "name", desc: "Name of the project." }, page: {name: "page", desc: "Page of the diary (only for diaries; 0 is mainpage)."} },
    execute: (flags, args, _raw, cmdIf) => {
        if (project.flags && checkFlagInclude(flags, project.flags.list)) {
            const result = ["Found the following projects:"];

            const projects = cmdIf.content.filter(p => p.type === "project");
            if (projects.length === 0) result.push("\tNo projects found.");
            else projects.forEach(project => result.push(`\t${project.name}\t${project.short_desc}`));

            result.push("And the following diaries:");
            const diaries = cmdIf.content.filter(p => p.type === "diary");
            if (diaries.length === 0) result.push("\tNo diaries found.");
            else diaries.forEach(diary => result.push(`\t${diary.name}\t${diary.short_desc}`));

            return result;
        }

        if (args.length < 1 || args.length > 2) return printSyntax(project);

        if (args[0] === "this") args[0] = "homepage";

        let [pjt] = [cmdIf.content.find(p => p.name === args[0]) as Project | Diary | undefined];
        if (!pjt) return [
            `Cannot find project ${args[0]}!`,
            "You can see available projects using 'project -l'."
        ];

        if (project.flags && checkFlagInclude(flags, project.flags.source)) {
            try {
                window && window.open(pjt.repo, "_blank");
                return ["Opened repository in new tab."];
            } catch {
                return ["Sorry, no repository for this project."];
            }
        }
        if (project.flags && checkFlagInclude(flags, project.flags.minimal)) return pjt.desc;

        const result: string[] = [];

        let selectedPage: number|undefined = Number.parseInt(args[1] || "");

        if (args[1]) {
            if(Number.isNaN(selectedPage)) {
                result.push("Invalid page number, ignoring it.");
                selectedPage = undefined;
            } else {
                if (pjt.type !== "diary") {
                    result.push("This is not a diary, ignoring page.");
                    selectedPage = undefined;
                } else {
                    if (selectedPage < 0 || selectedPage > pjt.entries.length) {
                        result.push("Invalid page number, ignoring it.");
                        selectedPage = undefined;
                    }
                }
            }
        } else {
            selectedPage = undefined;
        }

        if (cmdIf.callbacks?.setModalContent) cmdIf.callbacks.setModalContent(pjt, selectedPage);
        if (cmdIf.callbacks?.setModalVisible) cmdIf.callbacks.setModalVisible(true);
        return result;
    }
};

const exitCmd: Command = {
    name: "exit",
    desc: "Tries to close this tab.",
    execute: () => {
        if (typeof window !== undefined) {
            window.opener = null;
            window.open("", "_self");
            window.close();
        }
        return [
            "If you can read this, closing the window did not work.",
            "This is most likely because of a restriction in JavaScript.",
            "#{Read more here|https://developer.mozilla.org/en-US/docs/Web/API/Window/close}."
        ];
    }
};

const clear: Command = {
    name: "clear",
    desc: "Clears the output on screen.",
    execute: () => []
};

const getColors = () => {
    const replColor = window.document.documentElement.style.getPropertyValue("--repl-color") || window.getComputedStyle(document.documentElement).getPropertyValue("--repl-color") || "rgb(24, 138, 24)";
    const linkColor = window.document.documentElement.style.getPropertyValue("--repl-color-link") || window.getComputedStyle(document.documentElement).getPropertyValue("--repl-color-link") || "rgb(31, 179, 31)";
    const hintColor = window.document.documentElement.style.getPropertyValue("--repl-color-hint") || window.getComputedStyle(document.documentElement).getPropertyValue("--repl-color-hint") || "rgba(24, 138, 24, 0.3)";
    return [replColor, linkColor, hintColor];
};

const setColors = (color: Color) => {
    window?.document.documentElement.style.setProperty("--repl-color", color.string());
    window?.document.documentElement.style.setProperty("--repl-color-link", color.lighten(0.3).rgb().string());
    window?.document.documentElement.style.setProperty("--repl-color-hint", color.fade(0.7).string());
};

const color: Command = {
    name: "color",
    desc: "Changes the color of the site.",
    subcommands: {
        reset: { name: "reset", desc: "Resets the color." },
        value: { name: "value", desc: "Any valid (css) color value." },
    },
    execute: (_flags, args, _raw, cmdIf) => {
        if (!window || !window.document) return [];
        if (args.length === 0) {
            const colors = getColors();
            return [
                "Current colors:",
                `Text:\t\t${colors[0]}`,
                `Links:\t\t${colors[1]}`,
                `Completion:\t${colors[2]}`
            ];
        }
        if (args[0] === "reset") {
            window.document.documentElement.style.removeProperty("--repl-color");
            window.document.documentElement.style.removeProperty("--repl-color-link");
            window.document.documentElement.style.removeProperty("--repl-color-hint");
            return ["Color reset."];
        } else {
            let color: Color;
            try {
                color = Color(args.join(" ").trim());
            } catch {
                return ["Invalid color!"];
            }
            setColors(color);

            switch(true) {
                case color.hex().toLowerCase() === "#1f1e33": {
                    if (cmdIf.callbacks?.setModalHTML && cmdIf.callbacks?.setModalVisible) {
                        cmdIf.callbacks?.setModalHTML('<iframe width="560" height="315" src="https://www.youtube-nocookie.com/embed/w4U9S5eX3eY" title="YouTube video player" frameborder="0" allow="autoplay; clipboard-write; encrypted-media; picture-in-picture" allowfullscreen></iframe>');
                        cmdIf.callbacks?.setModalVisible(true);
                    }
                    break;
                }
            }

            return ["Color set | #{Link|#} | %{help}"];
        }
    }
};

const save: Command = {
    name: "save",
    desc: "Saves the current color and command history to local storage.",
    subcommands: {
        clear: { name: "clear", desc: "Clear the saved data." },
        confirm: { name: "confirm", desc: "You explicitly confirm, you allow saving to the local storage." }
    },
    execute: (_flags, args, _raw, cmdIf) => {
        const defaultRet = [
            "You can save the current color and command history to local storage.", 
            "To do so, use %{save confirm}.",
            "By using this command above you agree on saving the non-functional data to local storage.",
            "The data will never leave your computer!"
        ];

        if (args.length === 0) {
            return defaultRet;
        } else if (args[0] === "clear") {
            window.localStorage.clear();
            return ["Colors and history removed from storage."];
        } else if (args[0] === "confirm") {
            const result = [];

            const currentColors = getColors();
            const color = new Color(currentColors[0]);
            if(color.contrast(new Color("#000")) < 1.1 || color.alpha() < 0.1) result.push("Skipping saving the color because it's too dark.");
            else {
                window.localStorage.setItem("color", currentColors[0]);
                result.push("Color saved to local storage.");
            }

            const history = cmdIf.callbacks?.getCmdHistory ? cmdIf.callbacks.getCmdHistory() : [];
            window.localStorage.setItem("history", JSON.stringify(history));

            result.push("History saved to storage.");
            return result;
        } else {
            return printSyntax(save);
        }
    },
};

const pingi: Command = {
    name: "pingi",
    desc: "<3",
    execute: (_flags, _args, _raw, cmdIf) => {
        if (cmdIf.callbacks?.setModalHTML && cmdIf.callbacks.setModalVisible) {
            cmdIf.callbacks.setModalHTML('<img src="https://openai-labs-public-images-prod.azureedge.net/user-jomUNcw4rd0bDGfcOQUAbYNO/generations/generation-hJQFR4dpyyZskjmbAkvlnNYi/image.webp" />');
            cmdIf.callbacks.setModalVisible(true);
        }
        return ["<3"];
    },
    hidden: true
};

const blahaj: Command = {
    name: "blahaj",
    desc: "Blahaj is the best.",
    execute: () => {
        setColors(Color("#417988"));
        return [" _________         .    .",
                "(..       \\_    ,  |\\  /|",
                " \\       O  \\  /|  \\ \\/ / ",
                "  \\______    \\/ |   \\  / ",
                "     vvvv\\    \\ |   /  |",
                "    \\^^^^  ==   \\_/   |",
                "    `\\_   ===    \\.  |",
                "    / /\\_   \\ /      |",
                "    |/   \\_  \\|      /",
                "           \\________/"  ];
    },
    hidden: true
};

const ping: Command = {
    name: "ping",
    desc: "Ping!",
    execute: () => {
        return ["Pong!"];
    },
};

export const commandList = [about, help, man, project, exitCmd, clear, color, save, pingi, blahaj, ping].sort((a, b) => a.name.localeCompare(b.name));