#!/usr/bin/env python3
"""
map.py — md <-> Gitea JSON. The whole translation, and only the translation.

Pure functions: no network, no filesystem, no argparse. Give it a payload and
it hands back a domain Issue; give it an Issue and it hands back a request
body. That purity is the point — it can be reasoned about and tested without a
Gitea anywhere, and it is the single file to open when the two representations
disagree.

Direction of knowledge: this module imports the domain (issue.py) and is
imported by the transport's callers. The domain never imports this.

What crosses the boundary, and what does not:

    domain            Gitea                 note
    ----------------------------------------------------------------------
    id (slug)         —                     local only; the tracker never sees it
    title, body       title, body           verbatim, both ways
    state             state                 open/closed, same vocabulary
    labels            labels[]              names both ways; ids only on write
    assignees         assignees[]           logins
    milestone         milestone.title       resolved to an id on write
    depends           —                     slugs; #N is translated at the edge
    —                 number, html_url      lands in extra as gitea:/url:

`depends:` is the authoritative graph and is always slugs. The body's
`## Depends on` section is human prose and is passed through UNCHANGED in both
directions: a pull seeds `depends:` from the `#N` it finds there, and a push
never rewrites what the author wrote. Deliberate — a translator that edits
prose churns the body on every round trip.
"""
import os
import sys

sys.path.insert(0, os.path.normpath(os.path.join(
    os.path.dirname(os.path.abspath(__file__)), "..", "..", "issue", "scripts")))
import issue  # noqa: E402

# How the taxonomy is painted in Gitea's UI. A hex code says nothing about what
# an issue IS, which is exactly why it lives here and not in the domain.
LABEL_COLORS = {
    "type/bug": "#ee0701",
    "type/task": "#0e8a16",
    "type/refactor": "#1d76db",
    "type/test": "#fbca04",
    "type/feature": "#5319e7",
    "type/draft": "#cccccc",
    "severity/low": "#c2e0c6",
    "severity/medium": "#fbca04",
    "severity/high": "#eb6420",
    "severity/showstopper": "#ee0701",
    "severity/critical": "#b60205",
}
DEFAULT_COLOR = "#ededed"

# What this bridge writes into the domain's `origin:` field. The domain records
# that an issue exists somewhere else; only this module knows where.
ORIGIN = "gitea"


def label_specs(names):
    """{name: {color, description, exclusive}} for the transport to create.

    Exclusivity and meaning come from the domain taxonomy; only the color is
    decided here. `tea labels create` cannot set `exclusive` (as of 0.14.2),
    which is why these go through the API."""
    out = {}
    for name in names:
        desc = ""
        if name.startswith("type/"):
            desc = issue.TYPES.get(name.split("/", 1)[1], "")
        out[name] = {
            "color": LABEL_COLORS.get(name, DEFAULT_COLOR),
            "description": desc,
            "exclusive": name.startswith(issue.EXCLUSIVE_NS),
        }
    return out


def remote_key(repo, number):
    """Stable cross-repo handle: owner/repo#42."""
    return "%s#%d" % (repo, int(number))


def parse_remote_key(key):
    repo, _, num = (key or "").rpartition("#")
    return (repo, int(num)) if repo and num.isdigit() else (None, None)


# --------------------------------------------------------------------------
# Gitea -> domain
# --------------------------------------------------------------------------

def numbers_in_body(body):
    """`#N` referenced from the body's dependency sections, as ints. Used only
    to seed `depends:` on the first pull."""
    return [int(r[1:]) for r in issue.body_dep_refs(body) if r.startswith("#")]


def from_api(payload, id, repo, id_for_number=None, extra_numbers=(), synced=None):
    """Build a domain Issue from a Gitea issue payload.

    id_for_number maps a Gitea number to a local slug — dependencies whose
    target has not been pulled yet are dropped from `depends:` (the body still
    names them, so nothing is lost) rather than invented."""
    body = (payload.get("body") or "").strip()
    id_for_number = id_for_number or {}

    numbers = list(numbers_in_body(body))
    for n in extra_numbers:
        if n not in numbers:
            numbers.append(n)
    depends, unresolved = [], []
    for n in numbers:
        slug = id_for_number.get(n)
        if slug and slug != id and slug not in depends:
            depends.append(slug)
        elif not slug:
            unresolved.append(n)

    extra = {
        "gitea": remote_key(repo, payload["number"]),
        "url": payload.get("html_url", ""),
        "synced": synced or "",
    }
    if payload.get("updated_at"):
        extra["remote-updated"] = payload["updated_at"]
    if payload.get("comments"):
        extra["comments"] = payload["comments"]

    iss = issue.Issue(
        id=id,
        title=payload.get("title", ""),
        body=body,
        state=payload.get("state") or "open",
        labels=[l.get("name", "") for l in payload.get("labels") or []],
        assignees=[a.get("login", "") for a in payload.get("assignees") or []],
        milestone=(payload.get("milestone") or {}).get("title") or "",
        depends=depends,
        origin=ORIGIN,
        extra=extra)
    return iss, unresolved


def render_comments(comments):
    """Comment thread as flat markdown. Read-only: nothing writes it back."""
    out = []
    for c in comments:
        out.append("## comment %s — %s — %s" % (
            c.get("id"), (c.get("user") or {}).get("login", ""),
            (c.get("created_at") or "")[:10]))
        out.append("")
        out.append((c.get("body") or "(empty)").strip())
        out.append("")
    return "\n".join(out)


# --------------------------------------------------------------------------
# domain -> Gitea
# --------------------------------------------------------------------------

def to_payload(iss, label_ids=None, milestone_id=None, include_state=False):
    """Request body for POST /issues or PATCH /issues/{n}.

    The body is sent verbatim — see the module docstring on why slugs in
    `## Depends on` are not rewritten to `#N`."""
    payload = {"title": iss.title, "body": iss.body.strip()}
    if label_ids is not None:
        payload["labels"] = [label_ids[l] for l in iss.labels if l in label_ids]
    if iss.assignees:
        payload["assignees"] = list(iss.assignees)
    if milestone_id is not None:
        payload["milestone"] = milestone_id
    if include_state:
        payload["state"] = iss.state
    return payload


def apply_remote(iss, payload, repo, synced):
    """Stamp the sync-owned fields onto an issue after a successful write.
    Mutates and returns it; `origin` is the one domain field this touches."""
    iss.origin = ORIGIN
    iss.extra["gitea"] = remote_key(repo, payload["number"])
    iss.extra["url"] = payload.get("html_url", "")
    iss.extra["synced"] = synced
    if payload.get("updated_at"):
        iss.extra["remote-updated"] = payload["updated_at"]
    return iss


def number_of(iss):
    """Gitea number for an already-synced issue, or None."""
    _repo, n = parse_remote_key(iss.extra.get("gitea", ""))
    return n