import { composeServerCfg, parseCfg } from './config-compose.js';
import { selectedZombieMap, mapRotation } from './map-aliases.js';
import { configWarnings, type ConfigAssignment, type ConfigInspection, type ConfigSource } from '../../config-workbench.js';

export interface ConfigLayer { source: ConfigSource; text: string; }

/** Trace file composition, including assignments left in place by the composer.
 * This is an intended-file preview, not a query of live runtime dvars. */
export function inspectConfig(baseline: ConfigLayer, overlays: ConfigLayer[], game: string | null, map: string | null, mapSlug?: string | null): ConfigInspection {
    const sorted = [...overlays].sort((a, b) => a.source.id! - b.source.id!);
    const parsed = parseCfg(baseline.text);
    type TracedLine = { line: string; history: ConfigAssignment[] };
    function assignment(line: string, source: ConfigSource, index: number): ConfigAssignment {
        const match = /^\s*(?:(?:set|seta)\s+)(\S+)\s+(.*)$/i.exec(line)
            ?? /^\s*(sv_maprotation)\s+(.*)$/i.exec(line);
        return { value: match?.[2] ?? '', source, line: index + 1 };
    }
    const lines: TracedLine[] = parsed.order.map((entry, index) => ({
        line: entry.line, history: [assignment(entry.line, baseline.source, index)]
    }));
    const replacements = new Map<string, TracedLine>();
    const warnings = configWarnings(baseline.text, false).map(w => `${baseline.source.name}: ${w}`);
    for (const overlay of sorted) {
        warnings.push(...configWarnings(overlay.text, true).map(w => `${overlay.source.name}: ${w}`));
        overlay.text.split(/\r?\n/).forEach((line, index) => {
            const match = /^\s*set\s+(\S+)\s+/.exec(line);
            if (!match) return;
            const previous = replacements.get(match[1]);
            replacements.set(match[1], { line, history: [...(previous?.history ?? []), assignment(line, overlay.source, index)] });
        });
    }
    for (const [key, replacement] of replacements) {
        const index = parsed.entries.get(key);
        if (index === undefined) lines.push(replacement);
        else lines[index] = { line: replacement.line, history: [...lines[index].history, ...replacement.history] };
    }
    const sources = [baseline.source, ...sorted.map(o => o.source)];
    const selected = selectedZombieMap(game, map, mapSlug);
    if (selected) {
        const source: ConfigSource = { id: null, name: 'Server map selection', version: null, kind: 'map' };
        sources.push(source);
        const rotation = /^\s*(?:(?:set|seta)\s+)?sv_maprotation\s+/i;
        const history = lines.filter(entry => rotation.test(entry.line)).flatMap(entry => entry.history);
        for (let i = lines.length - 1; i >= 0; i--) if (rotation.test(lines[i].line)) lines.splice(i, 1);
        const line = `set sv_maprotation "${mapRotation(selected)}"`;
        lines.push({ line, history: [...history, assignment(line, source, 0)] });
    }
    const byKey = new Map<string, { key: string; history: ConfigAssignment[] }>();
    for (const entry of lines) {
        const match = /^\s*(?:set|seta)\s+(\S+)\s+/i.exec(entry.line) ?? /^\s*(sv_maprotation)\s+/i.exec(entry.line);
        if (!match) continue;
        const normalized = match[1].toLowerCase();
        const existing = byKey.get(normalized);
        byKey.set(normalized, { key: match[1], history: [...(existing?.history ?? []), ...entry.history] });
    }
    return {
        text: composeServerCfg(baseline.text, sorted.map(o => ({ id: o.source.id!, text: o.text })), game, map, mapSlug),
        sources, warnings,
        settings: [...byKey.values()].map(({ key, history }) => ({ key, history, value: history.at(-1)!.value, source: history.at(-1)!.source }))
            .sort((a, b) => a.key.localeCompare(b.key))
    };
}