"""Scriptwriter prompt builders (SPEC_NEW §7.5) — built in Phase 4.

Constraints encoded in the system prompt: spoken colloquial Swedish (talspråk —
"asså", "typ", natural contractions); each segment ≤ MAX_SPOKEN_WORDS words AND
sized so duration.decide_duration accepts it (split long bodies, never overrun an
8s clip — SPEC_NEW §12.1/§12.2); hook front-loads the claim in the first ~5 words;
CTA names the action concretely; numbers spelled out in Swedish words; no digits,
no quote characters.

The validator (prompts.veo_segment.validate_spoken_text + duration.decide_duration)
rejects oversize segments before they ever reach Veo — this prompt aims to never
trip it.
"""

from __future__ import annotations

import json
from typing import Any

from ..duration import MAX_SPOKEN_WORDS

SCRIPTWRITER_SYSTEM = f"""You write one short Swedish UGC video-ad script that an \
avatar says straight to camera. You are given a creative BRIEF (angle, hypothesis), \
the AVATAR's persona/voice, and a few WINNING HOOK examples to echo the style of.

You output three parts: a hook, zero to four body segments, and a cta. Each part is \
ONE spoken line — one clip in which the avatar says exactly that line to camera.

HARD RULES — every line must obey all of them:
- Colloquial spoken Swedish (talspråk): natural contractions, fillers like "asså", \
"typ", "liksom" where they fit. It must sound like a real person talking, not ad copy.
- EVERY line is at most {MAX_SPOKEN_WORDS} spoken words. Aim 6–14 words per body \
segment. If an idea needs more than {MAX_SPOKEN_WORDS} words, SPLIT it into two body \
segments — never overrun a single clip. Shorter lines sit on shorter clips (about \
nine words → four seconds, ten to fourteen → six seconds, fifteen to eighteen → \
eight seconds), so keep each line tight.
- The HOOK front-loads the main claim in the first ~5 words — the scroll-stopper \
comes first, no warm-up.
- The CTA names the action concretely (what to do next), in the avatar's voice.
- Spell out EVERY number or price in Swedish words ("trehundra kronor", never \
"300 kr"). NO digits anywhere.
- Do NOT use any quotation marks of any kind inside a line.
- Stay true to the brief's angle and hypothesis and the avatar's persona; do not \
invent forbidden or unsupported claims.

Output ONLY this JSON object — no prose, no markdown fences:
{{"hook": "string", "body_segments": ["string", ...], "cta": "string"}}"""


def build_user_prompt(
    brief: dict[str, Any],
    avatar: dict[str, Any],
    hook_examples: list[str] | None = None,
) -> str:
    """Render the brief + avatar persona + winning-hook examples into the user
    message (SPEC_NEW §7.5)."""
    persona = avatar.get("persona") or {}
    examples = [h for h in (hook_examples or []) if h and str(h).strip()]
    examples_block = (
        "\n".join(f"- {h}" for h in examples)
        if examples
        else "- (no proven hooks yet — write a fresh scroll-stopper)"
    )
    return (
        f"BRIEF\n"
        f'  angle: {brief.get("angle") or ""}\n'
        f'  mode: {brief.get("mode") or ""}\n'
        f'  hypothesis: {brief.get("hypothesis") or ""}\n'
        f'  rationale: {brief.get("rationale") or ""}\n\n'
        f"AVATAR\n"
        f'  name: {avatar.get("name") or ""}\n'
        f"  persona: {json.dumps(persona, ensure_ascii=False)}\n\n"
        f"WINNING HOOK EXAMPLES (echo this register, do not copy verbatim):\n"
        f"{examples_block}\n\n"
        f"Write the script as the JSON object {{hook, body_segments[], cta}}. "
        f"Keep every line short and in spoken Swedish."
    )