from __future__ import annotations

from typing import Any

from claridoc.models import Brief, Outline, Source, SourcePack


def build_evidence_map(brief: Brief, outline: Outline, sources: SourcePack) -> dict[str, Any]:
    source_by_id = {source.id: source for source in sources.sources}
    sections: list[dict[str, Any]] = []
    for section in outline.sections:
        evidence = []
        for source_id in section.evidence_ids:
            source = source_by_id.get(source_id)
            if source is None:
                continue
            evidence.append(_source_record(source))
        sections.append(
            {
                "section_id": section.id,
                "intent": section.intent,
                "title": section.title,
                "reader_question": section.reader_question,
                "decision_requirements": section.decision_requirements,
                "evidence": evidence,
                "evidence_gap": bool(section.decision_requirements and not evidence),
            }
        )
    return {
        "schema_version": 2,
        "document": brief.title,
        "citation_style": brief.constraints.citation_style,
        "reader_document_contains_internal_source_ids": brief.constraints.citation_style == "source_id",
        "sections": sections,
        "sources": [_source_record(source) for source in sources.sources],
    }


def render_provenance(brief: Brief, outline: Outline, sources: SourcePack) -> str:
    source_by_id = {source.id: source for source in sources.sources}
    lines = [
        "# Evidence and decision provenance",
        "",
        "> This is an internal sidecar. It is not reader-facing article content.",
        "> Source IDs, repository paths, line ranges, status labels, and access dates belong here—not in `document.md`.",
        "",
        f"- Document: **{brief.title}**",
        f"- Citation rendering: `{brief.constraints.citation_style}`",
        f"- Evidence sources: **{len(sources.sources)}**",
        "",
        "## Section evidence map",
        "",
        "| Section | Decision contract | Evidence | Status / location |",
        "|---|---|---|---|",
    ]
    for section in outline.sections:
        decision = ", ".join(section.decision_requirements) if section.decision_requirements else "—"
        if not section.evidence_ids:
            lines.append(f"| {escape(section.title)} | {escape(decision)} | **GAP** | No allocated evidence |")
            continue
        for position, source_id in enumerate(section.evidence_ids):
            source = source_by_id.get(source_id)
            if source is None:
                lines.append(f"| {escape(section.title)} | {escape(decision)} | `{source_id}` | Unknown source |")
                continue
            section_name = section.title if position == 0 else "↳"
            location = _location(source)
            status = source.status or "unspecified"
            lines.append(
                f"| {escape(section_name)} | {escape(decision if position == 0 else '—')} | "
                f"`{source.id}` {escape(source.title)} | `{escape(status)}` · {escape(location)} |"
            )
    lines.extend(["", "## Source details", ""])
    for source in sources.sources:
        lines.extend(
            [
                f"### `{source.id}` {source.title}",
                "",
                f"- Type: `{source.source_type}`",
                f"- Status: `{source.status or 'unspecified'}`",
                f"- Location: `{_location(source)}`",
                f"- Public/reference URL: `{source.url}`",
                f"- Claim IDs: {', '.join(f'`{item}`' for item in source.claim_ids) or '—'}",
                f"- Decision IDs: {', '.join(f'`{item}`' for item in source.decision_ids) or '—'}",
                f"- Retrieval priority: `{source.priority:.4f}`",
                "",
            ]
        )
    return "\n".join(lines).rstrip() + "\n"


def _source_record(source: Source) -> dict[str, Any]:
    return {
        "id": source.id,
        "title": source.title,
        "source_type": source.source_type,
        "status": source.status,
        "path": source.path,
        "heading": source.heading,
        "line_start": source.line_start,
        "line_end": source.line_end,
        "url": source.url,
        "accessed": source.accessed,
        "claim_ids": list(source.claim_ids),
        "decision_ids": list(source.decision_ids),
        "priority": source.priority,
    }


def _location(source: Source) -> str:
    location = source.path or source.url
    if source.heading:
        location += f" — {source.heading}"
    if source.line_start is not None:
        location += f" (lines {source.line_start}-{source.line_end or source.line_start})"
    return location


def escape(value: str) -> str:
    return value.replace("|", "\\|").replace("\n", " ")