// how lore shows itself in pi. one glyph per state, weight and brightness
// before hue (the theme's roles carry the hue; nothing here depends on
// telling two colors apart), a few lines at most, and a link out to the
// space instead of a record explorer.
import type { ImageContent, TextContent } from "@earendil-works/pi-ai";
import type { Theme } from "@earendil-works/pi-coding-agent";
import { Text } from "@earendil-works/pi-tui";

type LoreTheme = Pick<Theme, "fg" | "bold">;

export const PDSLS = "https://pds.ls";
export const SITE = "https://lore.waow.tech";

export const GLYPH = { own: "●", shared: "◇", unbound: "○", ok: "✓", warn: "!", link: "↗" } as const;

export type Line = { author: string; text: string };

export type Overview = {
	account: string;
	label: string;
	title: string;
	owner: string;
	mine: boolean;
	source: { key: string; kind: string; title: string };
	space: string;
	members: number | null;
	lines: Line[];
	total: number;
	all: boolean;
};

export type Note = { tone: "ok" | "info" | "warn"; text: string; hint?: string };

export const PREVIEW = 5;
const LINE_WIDTH = 96;

export const spaceLink = (space: string): string => `${PDSLS}/${space}`;

/** one line, ellipsized; entries are sentences, not documents */
export function clip(text: string, width = LINE_WIDTH): string {
	const flat = text.replace(/\s+/g, " ").trim();
	return flat.length <= width ? flat : `${flat.slice(0, width - 1).trimEnd()}…`;
}

export type StatusView = Overview | { account: string; unbound: true } | { loggedOut: true } | { account: string; waiting: string };

/** how long a save dialog waits for an answer before the tool gives up */
export const CONFIRM_MS = 120_000;

/** the three ways a save dialog ends. `unanswered` is a dialog nobody saw, which used to look
 * like an agent spinning forever: the tool was waiting, the status line said "working". */
export type Answer = "yes" | "no" | "unanswered";

export async function askToSave(confirm: (title: string, text: string, opts: { timeout: number }) => Promise<boolean>, where: string, text: string, timeout = CONFIRM_MS, now = Date.now): Promise<Answer> {
	const started = now();
	const ok = await confirm(`save to ${where}?`, text, { timeout });
	if (ok) return "yes";
	return now() - started >= timeout ? "unanswered" : "no";
}

/** what the footer shows all session: glyph, namespace, owner when shared, count, account */
export function statusLine(view: StatusView): string {
	if ("loggedOut" in view) return `${GLYPH.unbound} lore · not signed in`;
	if ("waiting" in view) return `${GLYPH.warn} lore · waiting for you: save to ${view.waiting}? answer the dialog · ${view.account}`;
	if ("unbound" in view) return `${GLYPH.unbound} lore · unbound · ${view.account}`;
	const owner = view.mine ? "" : ` ← ${view.owner}`;
	return `${view.mine ? GLYPH.own : GLYPH.shared} lore ${view.title}${owner} · ${view.total} · ${view.account}`;
}

/** the status as its own line below the editor, glyph in the accent role, the rest quiet */
export function renderStatus(view: StatusView, theme: LoreTheme): Text {
	const line = statusLine(view);
	const glyph = line.slice(0, 1);
	const rest = line.slice(1);
	if ("waiting" in view) return new Text(`${theme.fg("warning", glyph)}${theme.fg("text", rest)}`, 0, 0);
	const tone = "loggedOut" in view || "unbound" in view ? "dim" : "muted";
	return new Text(`${theme.fg("accent", glyph)}${theme.fg(tone, rest)}`, 0, 0);
}

export function renderOverview(view: Overview, theme: LoreTheme): Text {
	const glyph = theme.fg("accent", view.mine ? GLYPH.own : GLYPH.shared);
	const name = theme.fg("accent", theme.bold(view.title));
	const owner = view.mine ? theme.fg("dim", "yours") : theme.fg("muted", `← ${view.owner}`);
	const head = `${glyph} ${name}  ${owner}`;

	const meta = [
		`as ${view.account}`,
		view.source.kind === "name" ? undefined : `from ${view.source.title} (${view.source.kind})`,
		view.members === null ? undefined : view.members === 0 ? "no one else" : `${view.members} ${view.members === 1 ? "member" : "members"}`,
	]
		.filter((m): m is string => m !== undefined)
		.join(" · ");

	const lines: string[] = [head, theme.fg("dim", `  ${meta}`)];
	if (view.total === 0) {
		lines.push(theme.fg("muted", "  nothing remembered here yet"));
	} else {
		const shown = view.all ? view.lines : view.lines.slice(0, PREVIEW);
		const width = Math.max(12, ...shown.map((l) => l.author.length));
		for (const line of shown) {
			lines.push(`  ${theme.fg("muted", line.author.padEnd(width))}  ${theme.fg("text", clip(line.text))}`);
		}
		const rest = view.total - shown.length;
		if (rest > 0) lines.push(theme.fg("dim", `  +${rest} more · /lore all`));
	}
	lines.push(`  ${theme.fg("dim", GLYPH.link)} ${theme.fg("mdLinkUrl", spaceLink(view.space))}`);
	return new Text(lines.join("\n"), 0, 0);
}

/** the TUI face of a lore-update message: the same text, dimmed, under a glyph */
export function renderUpdateMessage(content: string | (TextContent | ImageContent)[], theme: LoreTheme): Text {
	const text = Array.isArray(content) ? content.flatMap((c) => (c.type === "text" ? [c.text] : [])).join("\n") : content;
	return new Text(`${theme.fg("accent", GLYPH.shared)} ${theme.fg("dim", text)}`, 0, 0);
}

export function renderNote(note: Note, theme: LoreTheme): Text {
	const glyph =
		note.tone === "ok" ? theme.fg("success", GLYPH.ok) : note.tone === "warn" ? theme.fg("warning", GLYPH.warn) : theme.fg("accent", "·");
	const lines = [`${glyph} ${theme.fg("text", note.text)}`];
	if (note.hint) lines.push(theme.fg("dim", `  ${note.hint}`));
	return new Text(lines.join("\n"), 0, 0);
}