"""FlowDeck — bookmark importers (v5.6.0, Phase 4).

Raindrop.io, Pocket, Readwise, Shaarli and generic Netscape bookmark files are
normalized into a FlowDeck collection (URL, description, tags, created date).
"""
from __future__ import annotations

import csv
import io
import json
import re
from datetime import UTC, datetime
from typing import Any

from app.services.importers._common import coerce_tags
from app.services.importers.base import (
    Importer,
    ImportResult,
    decode_text,
    make_collection,
    register_importer,
)

_SCHEMA = [
    {"name": "Title", "type": "title"},
    {"name": "URL", "type": "url"},
    {"name": "Description", "type": "text"},
    {"name": "Tags", "type": "multi_select"},
    {"name": "Created", "type": "date"},
]

_TAG_RE = re.compile(
    r"<h3[^>]*>(?P<folder>.*?)</h3>|<a\s+(?P<attrs>[^>]*?)>(?P<title>.*?)</a>",
    re.IGNORECASE | re.DOTALL,
)
_ATTR_RE = re.compile(r'([a-zA-Z_:-]+)\s*=\s*"([^"]*)"')


def _strip_tags(value: str) -> str:
    return re.sub(r"<[^>]+>", "", value or "").strip()


def _iso_from_epoch(value: Any) -> str:
    try:
        return datetime.fromtimestamp(int(str(value)[:10]), tz=UTC).date().isoformat()
    except (ValueError, TypeError, OSError, OverflowError):
        return ""


def _iso(value: Any) -> str:
    text = str(value or "").strip()
    if not text:
        return ""
    if re.fullmatch(r"\d{10}", text):
        return _iso_from_epoch(text)
    return text[:10] if re.match(r"^\d{4}-\d{2}-\d{2}", text) else text


def _row(title: str, url: str, description: str = "", tags=None, created: str = "") -> dict:
    props: dict[str, Any] = {}
    if url:
        props["URL"] = url
    if description:
        props["Description"] = description
    tag_list = coerce_tags(tags)
    if tag_list:
        props["Tags"] = tag_list
    if created:
        props["Created"] = created
    return {"title": (title or url or "Bookmark").strip()[:200], "properties": props}


def parse_netscape(html: str) -> list[dict]:
    """Parse a Netscape bookmark file (browser / Pocket / Raindrop HTML)."""
    rows: list[dict] = []
    folder = ""
    for match in _TAG_RE.finditer(html):
        if match.group("folder") is not None:
            folder = _strip_tags(match.group("folder"))
            continue
        attrs = dict(_ATTR_RE.findall(match.group("attrs") or ""))
        url = attrs.get("href") or attrs.get("HREF") or ""
        if not url:
            continue
        title = _strip_tags(match.group("title"))
        tags = attrs.get("tags") or attrs.get("TAGS") or folder
        rows.append(_row(title, url, tags=tags, created=_iso_from_epoch(attrs.get("add_date", ""))))
    return rows


def _csv_rows(text: str) -> list[dict]:
    reader = csv.DictReader(io.StringIO(text))
    return [{(k or "").strip().lower(): v for k, v in row.items()} for row in reader]


class _BookmarkBase(Importer):
    source_id = "bookmarks"
    label = "Signets"
    description = ""
    order = 44
    keywords: tuple[str, ...] = ()

    def _hint(self, filename: str, text: str) -> bool:
        low = filename.lower()
        return any(k in low or k in text.lower() for k in self.keywords)


@register_importer
class RaindropImporter(_BookmarkBase):
    source_id = "raindrop"
    label = "Raindrop.io"
    description = "Export Raindrop.io (CSV ou HTML) → collection de signets."
    extensions = (".csv", ".html", ".htm")
    order = 46
    keywords = ("raindrop",)

    def detect(self, filename: str, data: bytes) -> bool:
        text = decode_text(data)
        if not self._hint(filename, text):
            return False
        return filename.lower().endswith((".csv", ".html", ".htm"))

    def parse(self, filename: str, data: bytes) -> ImportResult:
        result = ImportResult(source=self.source_id)
        text = decode_text(data)
        rows: list[dict] = []
        if filename.lower().endswith(".csv"):
            for r in _csv_rows(text):
                rows.append(_row(
                    r.get("title", ""), r.get("url", ""),
                    r.get("note") or r.get("excerpt") or "",
                    r.get("tags", ""), _iso(r.get("created", "")),
                ))
        else:
            rows = parse_netscape(text)
        result.pages.append(make_collection("Raindrop", _SCHEMA, rows, source_path=filename))
        result.stats["rows"] = len(rows)
        return result.finalize()


@register_importer
class PocketImporter(_BookmarkBase):
    source_id = "pocket"
    label = "Pocket"
    description = "Export Pocket (CSV ou HTML) → collection de signets."
    extensions = (".csv", ".html", ".htm")
    order = 45
    keywords = ("pocket",)

    def detect(self, filename: str, data: bytes) -> bool:
        text = decode_text(data)
        if not self._hint(filename, text):
            return False
        return filename.lower().endswith((".csv", ".html", ".htm"))

    def parse(self, filename: str, data: bytes) -> ImportResult:
        result = ImportResult(source=self.source_id)
        text = decode_text(data)
        rows: list[dict] = []
        if filename.lower().endswith(".csv"):
            for r in _csv_rows(text):
                rows.append(_row(
                    r.get("title", ""), r.get("url", ""),
                    "", r.get("tags", ""), _iso(r.get("time_added", "")),
                ))
        else:
            rows = parse_netscape(text)
        result.pages.append(make_collection("Pocket", _SCHEMA, rows, source_path=filename))
        result.stats["rows"] = len(rows)
        return result.finalize()


@register_importer
class ReadwiseImporter(_BookmarkBase):
    source_id = "readwise"
    label = "Readwise"
    description = "Export Readwise (highlights CSV) → collection de surlignages."
    extensions = (".csv", ".md", ".markdown")
    order = 47
    keywords = ("readwise",)

    def detect(self, filename: str, data: bytes) -> bool:
        text = decode_text(data)
        if not self._hint(filename, text):
            return False
        if filename.lower().endswith(".csv"):
            header = text.splitlines()[0].lower() if text.strip() else ""
            return "highlight" in header or "book title" in header
        return True

    def parse(self, filename: str, data: bytes) -> ImportResult:
        result = ImportResult(source=self.source_id)
        text = decode_text(data)
        schema = [
            {"name": "Highlight", "type": "title"},
            {"name": "Book", "type": "text"},
            {"name": "Author", "type": "text"},
            {"name": "Note", "type": "text"},
            {"name": "Tags", "type": "multi_select"},
            {"name": "Highlighted at", "type": "date"},
        ]
        rows: list[dict] = []
        if filename.lower().endswith(".csv"):
            for r in _csv_rows(text):
                props: dict[str, Any] = {}
                if r.get("book title"):
                    props["Book"] = r["book title"]
                if r.get("book author"):
                    props["Author"] = r["book author"]
                if r.get("note"):
                    props["Note"] = r["note"]
                tags = coerce_tags(r.get("document tags") or r.get("tags"))
                if tags:
                    props["Tags"] = tags
                created = _iso(r.get("highlighted at", ""))
                if created:
                    props["Highlighted at"] = created
                rows.append({"title": (r.get("highlight") or "Highlight").strip()[:200], "properties": props})
        else:
            rows = [{"title": ln.lstrip("-* ").strip()[:200], "properties": {}} for ln in text.splitlines() if ln.strip()]
        result.pages.append(make_collection("Readwise", schema, rows, source_path=filename))
        result.stats["rows"] = len(rows)
        return result.finalize()


@register_importer
class ShaarliImporter(_BookmarkBase):
    source_id = "shaarli"
    label = "Shaarli"
    description = "Export Shaarli (JSON) → collection de signets."
    extensions = (".json",)
    order = 48
    keywords = ("shaarli",)

    def _records(self, data: bytes) -> list[dict] | None:
        try:
            obj = json.loads(decode_text(data))
        except Exception:  # noqa: BLE001
            return None
        if isinstance(obj, dict) and isinstance(obj.get("links"), list):
            obj = obj["links"]
        if isinstance(obj, list) and obj and all(isinstance(x, dict) and x.get("url") for x in obj):
            return obj
        return None

    def detect(self, filename: str, data: bytes) -> bool:
        if not filename.lower().endswith(".json"):
            return False
        return self._records(data) is not None

    def parse(self, filename: str, data: bytes) -> ImportResult:
        result = ImportResult(source=self.source_id)
        records = self._records(data) or []
        rows = [
            _row(r.get("title", ""), r.get("url", ""), r.get("description", ""),
                 r.get("tags", ""), _iso(r.get("created", "")))
            for r in records
        ]
        result.pages.append(make_collection("Shaarli", _SCHEMA, rows, source_path=filename))
        result.stats["rows"] = len(rows)
        return result.finalize()


@register_importer
class BookmarksImporter(_BookmarkBase):
    source_id = "bookmarks"
    label = "Signets HTML (navigateur)"
    description = "Fichier de signets Netscape HTML (Chrome/Firefox/Edge…)."
    extensions = (".html", ".htm")
    order = 49
    keywords = ()

    def detect(self, filename: str, data: bytes) -> bool:
        if not filename.lower().endswith((".html", ".htm")):
            return False
        text = decode_text(data)[:4000].lower()
        return "netscape-bookmark-file" in text or "<dt><a href" in text

    def parse(self, filename: str, data: bytes) -> ImportResult:
        result = ImportResult(source=self.source_id)
        rows = parse_netscape(decode_text(data))
        result.pages.append(make_collection("Bookmarks", _SCHEMA, rows, source_path=filename))
        result.stats["rows"] = len(rows)
        return result.finalize()