//
// sidebar.js — the four sidebar sections.
//
// Session state, pending approvals, tool activity, and changed files. Each is
// a flat list; the interesting behaviour lives in the context commands that
// main.js registers against the selections here.
//

const {
    throttle,
    relativize,
    basename,
    oneLine,
    modeLabel,
    formatCost,
    formatTokens,
} = require("./util.js");
const { friendlyToolName } = require("./session.js");
const { actionsFor } = require("./permissions.js");

const RELOAD_INTERVAL = 200;
const MAX_ACTIVITY_ROWS = 120;

const STATUS_LABEL = {
    idle: "Ready",
    starting: "Starting…",
    thinking: "Thinking…",
    working: "Working…",
    waiting: "Waiting for you",
    stopped: "Stopped",
    error: "Error",
};

function item(name, options = {}) {
    const treeItem = new TreeItem(name, TreeItemCollapsibleState.None);
    if (options.descriptiveText) treeItem.descriptiveText = options.descriptiveText;
    if (options.tooltip) treeItem.tooltip = options.tooltip;
    if (options.image) treeItem.image = options.image;
    if (options.path) treeItem.path = options.path;
    if (options.command) treeItem.command = options.command;
    if (options.contextValue) treeItem.contextValue = options.contextValue;
    if (options.identifier) treeItem.identifier = options.identifier;
    return treeItem;
}

class SessionProvider {
    constructor(context) {
        this.context = context;
    }

    getChildren(element) {
        if (element) return [];

        const session = this.context.session;
        const auth = this.context.authState;
        const rows = [];

        rows.push({
            kind: "status",
            name: STATUS_LABEL[session.status] || session.status,
            detail: session.statusDetail,
        });

        rows.push({ kind: "account", auth: auth });

        rows.push({
            kind: "model",
            name: session.model || this.context.configuredModel() || "Default model",
        });

        rows.push({
            kind: "mode",
            name: session.permissionMode
                ? modeLabel(session.permissionMode)
                : this.context.configuredPermissionMode(),
        });

        const cost = formatCost(session.usage.costUSD);
        const input = formatTokens(session.usage.inputTokens);
        const output = formatTokens(session.usage.outputTokens);
        if (cost || input || output) {
            rows.push({
                kind: "usage",
                cost: cost,
                tokens: input || output ? `${input || "0"} in / ${output || "0"} out` : null,
            });
        }

        return rows;
    }

    getTreeItem(element) {
        switch (element.kind) {
            case "status": {
                const treeItem = item(element.name, {
                    descriptiveText: element.detail ? oneLine(element.detail, 60) : "",
                    image: "__builtin.action",
                    contextValue: "status",
                });
                return treeItem;
            }

            case "account": {
                const auth = element.auth;
                const signedIn = auth && auth.loggedIn;
                return item(signedIn ? "Account" : "Not signed in", {
                    descriptiveText: this.context.describeAuth(),
                    command: signedIn ? "claudenova.authStatus" : "claudenova.signIn",
                    contextValue: "account",
                    tooltip: signedIn ? "Signed in through Claude Code" : "Sign in to Claude",
                });
            }

            case "model":
                return item("Model", {
                    descriptiveText: element.name,
                    command: "claudenova.setModel",
                    contextValue: "model",
                });

            case "mode":
                return item("Permissions", {
                    descriptiveText: element.name,
                    command: "claudenova.setPermissionMode",
                    contextValue: "mode",
                });

            case "usage":
                return item("Usage", {
                    descriptiveText: [element.cost, element.tokens].filter(Boolean).join(" · "),
                    contextValue: "usage",
                });

            default:
                return item(String(element.kind));
        }
    }

    getParent() {
        return null;
    }
}

class ApprovalsProvider {
    constructor(context) {
        this.context = context;
    }

    getChildren(element) {
        if (!element) return this.context.session.approvals.slice();

        // The choices for a request are rows beneath it, so a decision never
        // depends on a panel being open.
        if (element.request) {
            return actionsFor(element).map((action) =>
                Object.assign({ approval: element }, action)
            );
        }

        return [];
    }

    getTreeItem(element) {
        if (element.approval) {
            return item(element.label, {
                identifier: element.approval.requestId + ":" + element.id,
                contextValue: "approval-action",
                command: "claudenova.approvalAction",
                tooltip: element.label,
            });
        }

        const approval = element;
        const request = approval.request;
        const detail = approval.preview
            ? `+${approval.preview.additions} −${approval.preview.deletions}`
            : oneLine(approval.summary, 50);

        const treeItem = new TreeItem(
            friendlyToolName(request.tool_name),
            TreeItemCollapsibleState.Expanded
        );
        treeItem.descriptiveText = detail;
        treeItem.tooltip = approval.summary || request.tool_name;
        treeItem.image = "__builtin.action";
        treeItem.contextValue = "approval";
        treeItem.identifier = approval.requestId;
        return treeItem;
    }

    getParent(element) {
        return element && element.approval ? element.approval : null;
    }
}

class ActivityProvider {
    constructor(context) {
        this.context = context;
    }

    getChildren(element) {
        if (element) return [];

        const tools = this.context.session.entries.filter((entry) => entry.kind === "tool");
        return tools.slice(-MAX_ACTIVITY_ROWS).reverse();
    }

    getTreeItem(entry) {
        const marks = { running: "…", done: "", error: "failed", denied: "denied" };
        const detail = [oneLine(entry.summary, 48), marks[entry.state]].filter(Boolean).join(" · ");

        const treeItem = item(friendlyToolName(entry.name), {
            descriptiveText: detail,
            tooltip: entry.summary || entry.name,
            identifier: entry.id,
            contextValue: entry.filePath ? "activity-file" : "activity",
        });

        if (entry.filePath) {
            treeItem.path = entry.filePath;
            treeItem.command = "claudenova.openActivityFile";
        }

        return treeItem;
    }

    getParent() {
        return null;
    }
}

class ChangesProvider {
    constructor(context) {
        this.context = context;
    }

    getChildren(element) {
        if (element) return [];
        return Array.from(this.context.session.changedFiles.values());
    }

    getTreeItem(change) {
        const counts =
            change.additions !== null || change.deletions !== null
                ? `+${change.additions || 0} −${change.deletions || 0}`
                : null;

        const detail = [counts, change.edits > 1 ? `${change.edits} edits` : null]
            .filter(Boolean)
            .join(" · ");

        const treeItem = item(basename(change.path), {
            descriptiveText: detail,
            tooltip: relativize(change.path),
            path: change.path,
            identifier: change.path,
            contextValue: "change",
            command: "claudenova.openChangedFile",
        });

        return treeItem;
    }

    getParent() {
        return null;
    }
}

class Sidebar {
    /**
     * @param context an object exposing `session`, `authState`, `describeAuth()`,
     *                `configuredModel()` and `configuredPermissionMode()`.
     */
    constructor(context) {
        this.context = context;

        this.sessionView = new TreeView("claude.session", { dataProvider: new SessionProvider(context) });
        this.approvalsView = new TreeView("claude.approvals", { dataProvider: new ApprovalsProvider(context) });
        this.activityView = new TreeView("claude.activity", { dataProvider: new ActivityProvider(context) });
        this.changesView = new TreeView("claude.changes", { dataProvider: new ChangesProvider(context) });

        this.views = [this.sessionView, this.approvalsView, this.activityView, this.changesView];

        this.reload = throttle(() => {
            for (const view of this.views) {
                view.reload().catch(() => {
                    /* the view may not be visible yet */
                });
            }
        }, RELOAD_INTERVAL);
    }

    dispose() {
        this.reload.cancel();
        for (const view of this.views) {
            try {
                view.dispose();
            } catch (_) {
                /* already disposed */
            }
        }
    }
}

module.exports = { Sidebar };