/**
 * Tests for the agent-thinking panel renderer in components/progress.js
 * (the `updateAgentThinking` function).
 *
 * Regression coverage for the "Using web_search" display bug
 * (PR #4470 / fix/display-actual-engine-name):
 *
 * The LangGraph strategy puts the friendly engine name in the progress
 * event's `data.message` (e.g. `🔍 Searching DuckDuckGo: "..."`) while
 * keeping the stable tool id in `data.tool` ("web_search"). The renderer
 * must surface the friendly message, not "Using web_search".
 *
 * The MCP strategy puts the friendly label in `data.message`
 * (`ACTION: Using DuckDuckGo - "..."`) AND also supplies `data.arguments`.
 * The renderer must show the message verbatim without duplicating the
 * query that's already embedded in it.
 *
 * When no message is supplied, the renderer falls back to
 * `Using ${data.tool}` (+ args), so the panel never renders blank.
 */

let progressComponent;

beforeAll(async () => {
    // progress.js is an IIFE; importing it runs the module and exposes
    // window.progressComponent (which now includes updateAgentThinking).
    await import('@js/components/progress.js');
    progressComponent = window.progressComponent;
});

beforeEach(() => {
    // updateAgentThinking queries these two ids and appends step nodes.
    document.body.innerHTML = `
        <div id="agent-thinking-panel" style="display: none;">
            <div id="agent-thinking-content"></div>
        </div>
    `;
});

function renderToolCall(data) {
    progressComponent.updateAgentThinking({ phase: 'tool_call', ...data });
    const step = document
        .getElementById('agent-thinking-content')
        .querySelector('.ldr-agent-step-content');
    return step ? step.textContent : null;
}

describe('updateAgentThinking - tool_call rendering', () => {
    it('shows the LangGraph friendly message instead of "Using web_search"', () => {
        const content = renderToolCall({
            tool: 'web_search', // stable id, must NOT be the display source
            message: '🔍 Searching DuckDuckGo: "climate policy"',
            iteration: 1,
        });

        expect(content).toBe('🔍 Searching DuckDuckGo: "climate policy"');
        expect(content).not.toContain('web_search');
        expect(content).not.toContain('Using ');
    });

    it('shows the MCP friendly message without duplicating the query', () => {
        const content = renderToolCall({
            tool: 'DuckDuckGo',
            message: 'ACTION: Using DuckDuckGo - "climate policy"',
            arguments: { query: 'climate policy' },
        });

        expect(content).toBe('ACTION: Using DuckDuckGo - "climate policy"');
        // The query is embedded in the message; it must appear exactly once
        // (no extra `\nQuery: "..."` appended from data.arguments).
        const occurrences = content.split('climate policy').length - 1;
        expect(occurrences).toBe(1);
        expect(content).not.toContain('Query:');
    });

    it('falls back to "Using <tool>" with query when no message is present', () => {
        const content = renderToolCall({
            tool: 'web_search',
            arguments: { query: 'climate policy' },
        });

        expect(content).toBe('Using web_search\nQuery: "climate policy"');
    });

    it('falls back to "Using unknown" when neither message nor tool is present', () => {
        const content = renderToolCall({});

        expect(content).toBe('Using unknown');
    });
});

function renderObservation(data) {
    progressComponent.updateAgentThinking({ phase: 'observation', ...data });
    const step = document
        .getElementById('agent-thinking-content')
        .querySelector('.ldr-agent-step-content');
    return step ? step.textContent : null;
}

describe('updateAgentThinking - observation rendering', () => {
    it('keeps the "From {engine}" attribution and appends data.content beneath it', () => {
        const content = renderObservation({
            message: '📄 From the web (SearXNG): [1] Some Title (http://a.com) Snip',
            content: '[1] Some Title (http://a.com)\nThe full snippet body.',
        });

        expect(content).toBe(
            '📄 From the web (SearXNG): [1] Some Title (http://a.com) Snip\n'
            + '[1] Some Title (http://a.com)\nThe full snippet body.'
        );
    });

    it('shows the message alone when no content is attached (short outputs)', () => {
        const content = renderObservation({
            message: '📄 From PubMed: No results.',
        });

        expect(content).toBe('📄 From PubMed: No results.');
    });

    it('falls back to content when no message is present', () => {
        const content = renderObservation({
            content: 'raw tool output only',
        });

        expect(content).toBe('raw tool output only');
    });

    it('truncates the composed result to 800 chars', () => {
        const content = renderObservation({
            message: '📄 From arXiv: long',
            content: 'z'.repeat(1000),
        });

        expect(content.length).toBe(803); // 800 + '...'
        expect(content.endsWith('...')).toBe(true);
        expect(content.startsWith('📄 From arXiv: long\n')).toBe(true);
    });
});