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This module gives us two things:\n *\n * 1. **Gated verbose logging.** `dbg.info(tag, ...)` etc. are no-ops\n * unless the consumer sets `globalThis.AVBRIDGE_DEBUG = true` (or\n * uses the matching `?avbridge_debug` URL search param at dev time).\n * When enabled, every log is prefixed with `[avbridge:]` so the\n * console is filterable.\n *\n * 2. **Unconditional self-diagnosis.** `dbg.warnIf(cond, tag, ...)`\n * always fires when a suspicious condition is detected, even with\n * debug off. These are the things we *know* mean something is\n * broken or degraded and the user would want to know about — e.g.\n * the cold-start gate timing out, the decoder running slower than\n * realtime, a libav variant taking longer to load than any network\n * should take, >20% of packets getting rejected.\n *\n * The guiding principle: **if a symptom caused more than 10 minutes of\n * human debugging once, add a targeted warning so the next instance\n * self-identifies in the console.** This module is where those\n * warnings live.\n */\n\n/** Read the debug flag fresh on every call so it's runtime-toggleable. */\nfunction isDebugEnabled(): boolean {\n if (typeof globalThis === \"undefined\") return false;\n const g = globalThis as { AVBRIDGE_DEBUG?: unknown };\n if (g.AVBRIDGE_DEBUG === true) return true;\n // Convenience: if running in a browser with a `?avbridge_debug` search\n // param, flip the flag on automatically. 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Modern formats\n * only (mp4/mkv/webm/ogg/wav/...) — designed to bridge to WebCodecs.\n *\n * - **default** — npm `@libav.js/variant-default`, ~12 MB. Audio-only build\n * (Opus, FLAC, WAV) despite the name. Useful for audio fallback.\n *\n * - **avbridge** — a custom build produced by `scripts/build-libav.sh` and\n * landing in `vendor/libav/`. Includes the AVI/ASF/FLV/MKV demuxers plus\n * the legacy decoders (WMV3, MPEG-4 Part 2, MS-MPEG4 v1/2/3, VC-1, MPEG-1/2,\n * AC-3/E-AC-3, WMAv1/v2/Pro). This is the only variant that can read AVI;\n * the npm variants are intentionally minimal and ship none of the legacy\n * demuxers.\n *\n * Variant resolution always goes through a runtime URL + `/* @vite-ignore *\\/`\n * dynamic import. Static imports trigger Vite's optimized-deps pipeline,\n * which rewrites `import.meta.url` away from the real `dist/` directory and\n * breaks libav's sibling-binary loading.\n */\n\nimport { dbg } from \"../../util/debug.js\";\n\nexport type LibavVariant = \"webcodecs\" | \"default\" | \"avbridge\";\n\nexport interface LoadLibavOptions {\n /**\n * Force threading on/off for this load. If unspecified, defaults to\n * \"true if `crossOriginIsolated`, otherwise false\". 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Decode wants pthreads for speed; probe\n // forces them off because libav.js's cross-thread reader-device protocol\n // is unreliable mid-`avformat_find_stream_info` for some AVI files.\n return {\n base,\n nothreads: !wantThreads,\n yesthreads: wantThreads,\n };\n}\n\nfunction libavBaseUrl(): string {\n // Consumer override — the documented \"LGPL replaceability\" hook.\n // Setting `globalThis.AVBRIDGE_LIBAV_BASE = \"/my/path\"` lets anyone swap\n // in a different libav build (custom fragments, security patches, etc.)\n // without rebuilding avbridge.\n const override =\n typeof globalThis !== \"undefined\"\n ? (globalThis as { AVBRIDGE_LIBAV_BASE?: string }).AVBRIDGE_LIBAV_BASE\n : undefined;\n if (override) return override;\n\n // Default: resolve relative to this module's URL. When avbridge is installed\n // under `node_modules/avbridge/`, this module lives at `dist/chunk-*.js` (or\n // `dist/element-browser.js` for the browser entry) and `../vendor/libav`\n // resolves to `node_modules/avbridge/vendor/libav`, where the build step\n // vendored every variant's binaries. That's the zero-config path.\n //\n // `import.meta.url` throws in some synthetic environments (CJS tests, some\n // SSR evaluators). If it fails, fall back to the legacy `/libav` path so\n // consumers who relied on the pre-2.1 behavior still work.\n try {\n return new URL(\"../vendor/libav\", import.meta.url).href;\n } catch {\n if (typeof location !== \"undefined\" && location.protocol.startsWith(\"http\")) {\n return `${location.origin}/libav`;\n }\n return \"/libav\";\n }\n}\n\nfunction chain(message: string, err: unknown): Error {\n const inner = err instanceof Error ? err.message : String(err);\n // eslint-disable-next-line no-console\n console.error(`[avbridge] ${message}:`, err);\n return new Error(`${message}: ${inner || \"(no message — see browser console)\"}`);\n}\n\ninterface LoadedVariant {\n LibAV: (opts?: Record) => Promise>;\n}\n\n/** Loose structural type — the AVI probe and the fallback decoder add fields. */\nexport type LibavInstance = Record & {\n mkreadaheadfile(name: string, blob: Blob): Promise;\n unlinkreadaheadfile(name: string): Promise;\n};\n"]}