import { describe, expect, it } from 'vitest';
import {
    OPENCODE_PROVIDER_TEXT_MAX_LENGTH,
    formatOpencodePromptError,
    truncateOpencodeProviderText
} from './opencodeErrorText';

/** The wording this path rendered before the reason was wired through. */
const FALLBACK = 'OpenCode prompt failed. Check logs for details.';

describe('truncateOpencodeProviderText', () => {
    it('leaves text that already fits untouched', () => {
        const text = 'Rate limit exceeded: free-models-per-day.';
        expect(truncateOpencodeProviderText(text)).toBe(text);
    });

    it('caps text no provider bounds, marking that it was cut', () => {
        // Measured: a provider answering a rate limit with a 20KB body
        // produces a 20,210-character message, forwarded verbatim.
        const capped = truncateOpencodeProviderText('x'.repeat(20_210));

        expect(capped).toHaveLength(OPENCODE_PROVIDER_TEXT_MAX_LENGTH);
        expect(capped.endsWith('…')).toBe(true);
    });
});

describe('formatOpencodePromptError', () => {
    it('states the provider reason the ACP transport already delivered', () => {
        const error = new Error('Internal error: Rate limit exceeded: free-models-per-day. Add credits to unlock 1000 free models.');

        expect(formatOpencodePromptError(error)).toBe(
            'OpenCode prompt failed: Rate limit exceeded: free-models-per-day. Add credits to unlock 1000 free models.'
        );
    });

    it('does not relay a rejection that arrives without the JSON-RPC wrapper', () => {
        // The wrapper is the only evidence the text came back over the wire
        // from OpenCode rather than being built locally by the transport.
        expect(formatOpencodePromptError(new Error('Session not found'))).toBe(FALLBACK);
    });

    it('does not mistake a message that merely mentions an internal error for the wrapper', () => {
        // Anchored: only a message that starts with it is agent-authored.
        expect(formatOpencodePromptError(new Error('The provider reported an Internal error: upstream')))
            .toBe(FALLBACK);
    });

    it('reads a rejection thrown as a bare string', () => {
        expect(formatOpencodePromptError('Internal error: Overloaded'))
            .toBe('OpenCode prompt failed: Overloaded');
    });

    it('reads a rejection thrown as a plain JSON-RPC error object', () => {
        expect(formatOpencodePromptError({
            code: -32603,
            message: 'Internal error: Overloaded',
            data: { service: 'session', errorName: 'APIError' }
        })).toBe('OpenCode prompt failed: Overloaded');
    });

    it('collapses embedded newlines so one failure stays one timeline line', () => {
        expect(formatOpencodePromptError(new Error('Internal error: Rate limit exceeded.\n\n  Try again later.')))
            .toBe('OpenCode prompt failed: Rate limit exceeded. Try again later.');
    });

    it('caps a message no provider bounds', () => {
        const formatted = formatOpencodePromptError(new Error(`Internal error: ${'y'.repeat(20_210)}`));

        expect(formatted).toBe(`OpenCode prompt failed: ${'y'.repeat(OPENCODE_PROVIDER_TEXT_MAX_LENGTH - 1)}…`);
    });

    it('keeps the original wording when there is no message', () => {
        expect(formatOpencodePromptError(new Error(''))).toBe(FALLBACK);
        expect(formatOpencodePromptError(new Error('   '))).toBe(FALLBACK);
    });

    it('keeps the original wording when the wrapper is all there was', () => {
        // A bare "Internal error:" says nothing the fallback does not.
        expect(formatOpencodePromptError(new Error('Internal error: '))).toBe(FALLBACK);
    });


    it('does not relay a rejection OpenCode did not author', () => {
        // AcpStdioTransport builds this one itself on process close and
        // appends up to 4KB of raw subprocess stderr to the message. Relaying
        // it would publish local stderr, credentials included, to the remote
        // timeline.
        const closeError = new Error(
            'ACP process exited (code=1, signal=null). stderr: AWS_SECRET_ACCESS_KEY=wJalrXUt shutting down'
        );

        const formatted = formatOpencodePromptError(closeError);

        expect(formatted).toBe(FALLBACK);
        expect(formatted).not.toContain('AWS_SECRET_ACCESS_KEY');
        expect(formatted).not.toContain('stderr');
    });

    it('does not relay the transport\'s own timeout', () => {
        expect(formatOpencodePromptError(new Error("ACP request 'session/prompt' timed out after 1000ms")))
            .toBe(FALLBACK);
    });

    it('keeps the original wording for a rejection that is not an error at all', () => {
        expect(formatOpencodePromptError(null)).toBe(FALLBACK);
        expect(formatOpencodePromptError(undefined)).toBe(FALLBACK);
        expect(formatOpencodePromptError(42)).toBe(FALLBACK);
        expect(formatOpencodePromptError({ code: -32603 })).toBe(FALLBACK);
    });
});