"""
FastAPI app and routes: gitweb actions as path operations.
Ported from gitweb/gitweb.perl dispatch and action handlers.
"""

from __future__ import annotations

import os
from contextlib import asynccontextmanager
from datetime import UTC, datetime
from pathlib import Path
from typing import Annotated
from urllib.parse import quote

import pygit2
from fastapi import FastAPI, File, Form, HTTPException, Query, Request, UploadFile
from fastapi.responses import HTMLResponse, PlainTextResponse, RedirectResponse
from fastapi.staticfiles import StaticFiles

from pygitweb import __meta__
from pygitweb.actions import (
	git_blob,
	git_blobdiff,
	git_blobpatch,
	git_commit,
	git_commitdiff,
	git_heads,
	git_history,
	git_log,
	git_object,
	git_patch,
	git_patches,
	git_remotes,
	git_shortlog,
	git_summary,
	git_tag,
	git_tags,
	git_tree,
	parse_pagination,
	summary_ref_options,
	summary_ref_state,
)
from pygitweb.api.plugins.project_zip import ProjectZip
from pygitweb.api.project import Project
from pygitweb.api.subpage import Subpage
from pygitweb.config import ACTIONS, get_loadavg, settings
from pygitweb.formatting import age_string
from pygitweb.git_helpers import git_get_references, git_get_type
from pygitweb.projects import git_get_project_owner, git_get_projects_list
from pygitweb.settings import router as settings_router
from pygitweb.tasks import (
	board_router,
	comment_router,
	create_board_for_project,
	get_board_tasks_grouped,
	task_router,
)
from pygitweb.templates_env import POSTAMBLE, PREAMBLE, env, jinja_escape
from pygitweb.timeline_cache import clear_timeline_cache_async, get_all_timeline_events, warm_timeline_cache_async
from pygitweb.validation import is_valid_pathname, is_valid_project

try:
	from pygitweb_pytesthtml.subpage_pytesthtml import SubpagePytestHtml
except ImportError:
	SubpagePytestHtml = None


@asynccontextmanager
async def timeline_cache_lifespan(app: FastAPI) -> None:
	warm_timeline_cache_async()
	yield
	clear_timeline_cache_async()


with open("pygitweb/README.md", encoding="utf-8") as _readme_file:
	_app_description = _readme_file.read()

app = FastAPI(
	debug=(settings.AUTH is None),
	title="PyGitWeb",
	summary="FastAPI + Pygit2 Repo Browser",
	description=_app_description,
	version=__meta__.__version__,
	lifespan=timeline_cache_lifespan,
)

SUBPAGES: list[Subpage] = []
if SubpagePytestHtml is not None:
	SUBPAGES.append(SubpagePytestHtml())

# Todo handle with nginx route
_static_dir = Path(__file__).parent / "static"
if _static_dir.is_dir():
	app.mount("/static", StaticFiles(directory=str(_static_dir)), name="static")


def _project_in_list(project: str) -> bool:
	lst = git_get_projects_list(
		filter_path="",
		paranoid=settings.STRICT_EXPORT,
		export_ok=settings.EXPORT_OK,
	)
	return any(p.get("path") == project for p in lst)


_auth_provider = None


def _get_auth_provider():
	"""Return auth provider instance if settings.AUTH is set; None if auth disabled."""
	global _auth_provider
	if not settings.AUTH:
		return None
	if _auth_provider is not None:
		return _auth_provider
	try:
		mod_name, _, cls_name = settings.AUTH.rpartition(".")
		mod = __import__(mod_name, fromlist=[cls_name])
		cls = getattr(mod, cls_name)
		admin_user = settings.ADMIN_USER.encode("utf-8") if settings.ADMIN_USER else None
		admin_password = settings.ADMIN_PASSWORD.encode("utf-8") if settings.ADMIN_PASSWORD else None
		_auth_provider = cls(
			admin_user=admin_user,
			admin_password=admin_password,
			session_timeout=settings.SESSION_TIMEOUT,
		)
	except Exception:
		_auth_provider = None
	return _auth_provider


def _request_can_add_project(request: Request) -> bool:
	"""True if auth is disabled or request has a valid session (header X-Session-Token or param/cookie session)."""
	if not settings.AUTH:
		return True
	provider = _get_auth_provider()
	if provider is None:
		return False
	token = (
		request.headers.get("X-Session-Token") or request.query_params.get("session") or request.cookies.get("session")
	)
	if not token:
		return False
	return getattr(provider, "validate_session", lambda _: False)(token)


app.include_router(settings_router)
app.include_router(board_router, prefix="/board")
app.include_router(task_router, prefix="/tasks")
app.include_router(comment_router, prefix="/comments")


@app.middleware("http")
async def loadavg_middleware(request: Request, call_next):
	try:
		if settings.MAXLOAD is not None and get_loadavg() > settings.MAXLOAD:
			raise RuntimeError("503:The load average on the server is too high")
	except RuntimeError as e:
		msg = str(e)
		if msg.startswith("503:"):
			raise HTTPException(status_code=503, detail=msg[4:]) from e
		raise
	return await call_next(request)


def _validate_project(project: str | None) -> str:
	if not project:
		raise HTTPException(status_code=400, detail="Project needed")
	if not is_valid_project(
		project,
		settings.PROJECTROOT,
		settings.EXPORT_OK,
		settings.STRICT_EXPORT,
		_project_in_list,
	):
		raise HTTPException(status_code=404, detail="No such project")
	return project


def _project_subpage_rows(project: str) -> list[list[str]]:
	project_enc = quote(project, safe="/")
	rows: list[list[str]] = []
	for subpage in SUBPAGES:
		link_label = subpage.link_name(project)
		if not link_label:
			continue
		subpage_name = subpage.subpage_name()
		rows.append([
			jinja_escape(link_label) or "",
			f'<a href="/project/{project_enc}/subpage/{quote(subpage_name, safe="")}">view</a>',
		])
	return rows


# ---------- Routes (no project) ----------


@app.get("/", response_class=HTMLResponse)
def git_project_list(
	request: Request,
	a: Annotated[str | None, Query(alias="a")] = None,
	pf: Annotated[str | None, Query(alias="pf")] = None,
	o: Annotated[str | None, Query(alias="o")] = None,
):
	"""Project list page. Port of git_project_list."""
	if a and a != "project_list":
		raise HTTPException(status_code=400, detail="Unknown action")
	if o and o not in ("none", "project", "descr", "owner", "age"):
		raise HTTPException(status_code=400, detail="Unknown order parameter")
	project_filter = pf or ""
	list_ = git_get_projects_list(
		filter_path=project_filter,
		paranoid=settings.STRICT_EXPORT,
		export_ok=settings.EXPORT_OK,
	)
	if not list_:
		raise HTTPException(status_code=404, detail="No projects found")

	def board_cell(pr: dict) -> str:
		path = pr.get("path", "")
		path_enc = quote(path, safe="/")
		try:
			board_refs = git_get_references(path, "refs/tags/boards")
			has_boards = len(board_refs) > 0
		except Exception:
			has_boards = False
		if has_boards:
			return f'<a href="/project/{path_enc}/board/">project board</a>'
		grey_style = ' style="color: #999; cursor: not-allowed;"' if settings.AUTH else ""
		proj_q = quote(path, safe="")
		return f'<a href="/board/create?project={proj_q}"{grey_style}>create board</a>'

	# We need better escaping logic here but can wait until we harden the templates
	table = env.get_template("table.html").render(
		cols=["Project", "Description", "Board"],
		rows=[
			[
				f"<a href='/project/{quote(pr.get('path', ''), safe='/')}'>{jinja_escape(pr.get('path', ''))}</a>",
				jinja_escape(pr.get("descr") or pr.get("path", "")),
				board_cell(pr),
			]
			for pr in list_[:50]
		],
	)
	pre = PREAMBLE.render(title=f"{settings.SITE_NAME} - Projects", site_name=settings.SITE_NAME)
	return HTMLResponse(f"{pre}<h1>Project List</h1>{table}{POSTAMBLE}")


@app.get("/index", response_class=PlainTextResponse)
def git_project_index(
	pf: Annotated[str | None, Query(alias="pf")] = None,
):
	"""Plain text project index (path owner). Port of git_project_index."""
	from urllib.parse import quote_plus

	projects = git_get_projects_list(
		filter_path=pf or "",
		paranoid=settings.STRICT_EXPORT,
		export_ok=settings.EXPORT_OK,
	)
	if not projects:
		raise HTTPException(status_code=404, detail="No projects found")
	lines = []
	for pr in projects:
		path = pr.get("path", "")
		owner = pr.get("owner") or git_get_project_owner(path) or ""
		path_enc = quote_plus(path, safe="/")
		owner_enc = quote_plus(owner, safe="/")
		lines.append(f"{path_enc} {owner_enc}")
	return PlainTextResponse("\n".join(lines), media_type="text/plain; charset=utf-8")


@app.get("/activity", response_class=HTMLResponse)
def activity_page(
	request: Request,
	page: Annotated[str | None, Query(alias="page")] = None,
	pagecount: Annotated[str | None, Query(alias="pagecount")] = None,
) -> HTMLResponse:
	p, pc = parse_pagination(page, pagecount)
	all_events = get_all_timeline_events()
	skip = (p - 1) * pc
	events_page = all_events[skip : skip + pc + 1]
	has_next = len(events_page) > pc
	if has_next:
		events_page = events_page[:pc]
	rows: list[list[str]] = []
	for item in events_page:
		project_name = item["project"]
		event = item["event"]
		oid = event["oid"]
		if event["kind"] == "commit":
			event_label = f"<a href='/project/{quote(project_name, safe='/')}"
			event_label += f"?a=commit&h={quote(oid, safe='')}'>{jinja_escape(oid[:7])}</a>"
		else:
			event_label = jinja_escape(event["kind"]) or ""
		description_raw = event.get("description")
		if not description_raw:
			description = ""
		elif "\n" in description_raw:
			description = description_raw.splitlines()[0][:80].rstrip() + "..."
		elif len(description_raw) > 80:
			description = description_raw[:80].rstrip() + "..."
		else:
			description = description_raw
		try:
			age_seconds = datetime.now(UTC).timestamp() - float(event["timestamp"])
			activity_time = "right now" if age_seconds <= 0 else age_string(age_seconds)
		except (ValueError, OSError):
			activity_time = ""
		rows.append([
			jinja_escape(activity_time) or "",
			f"<a href='/project/{quote(project_name, safe='/')}'>{jinja_escape(project_name)}</a>",
			event_label,
			jinja_escape(description) or "",
		])
	table = env.get_template("table.html").render(
		cols=["Time", "Project Name", "Event", "Description"],
		rows=rows,
	)
	prev_url = ""
	next_url = ""
	if p > 1:
		prev_url = f"{request.url.path}?page={p - 1}&pagecount={pc}"
	if has_next:
		next_url = f"{request.url.path}?page={p + 1}&pagecount={pc}"
	pagination_html = env.get_template("pagination.html").render(
		current_page=p,
		pagecount=pc,
		has_prev=p > 1,
		has_next=has_next,
		prev_url=prev_url,
		next_url=next_url,
		total_pages=None,
		page_links=None,
	)
	pre = PREAMBLE.render(title=f"{settings.SITE_NAME} - Activity", site_name=settings.SITE_NAME)
	return HTMLResponse(f"{pre}<h1>Activity</h1>{table}{pagination_html}{POSTAMBLE}")


@app.get("/opml", response_class=PlainTextResponse)
def git_opml():
	"""OPML feed list. Port of git_opml (stub)."""
	projects = git_get_projects_list(export_ok=settings.EXPORT_OK)
	# Minimal OPML
	lines = ['<?xml version="1.0"?><opml version="1.0"><head><title>Git</title></head><body>']
	for pr in projects[:100]:
		path = pr.get("path", "")
		lines.append(f'<outline text="{jinja_escape(path)}" />')
	lines.append("</body></opml>")
	return PlainTextResponse("\n".join(lines), media_type="text/xml; charset=utf-8")


@app.get("/board/create", response_class=RedirectResponse)
def board_create_page(
	request: Request,
	project: Annotated[str | None, Query(alias="p")] = None,
) -> RedirectResponse:
	"""Create a board named 'Tasks' (refs/tags/boards/Tasks) and redirect to the project summary."""
	if settings.AUTH:
		raise HTTPException(status_code=401, detail="Authentication required")
	p = project or request.query_params.get("project")
	if not p:
		raise HTTPException(status_code=400, detail="Project needed (use ?project= or ?p=)")
	_validate_project(p)
	try:
		create_board_for_project(p, name="Tasks", description="")
	except HTTPException as e:
		if e.status_code == 409:
			pass
		else:
			raise
	p_url = quote(p, safe="/")
	return RedirectResponse(url=f"/project/{p_url}", status_code=303)


# ---------- Add project ----------

_OPTIONAL_REPO_ZIP = File(default=None)


@app.get("/projectnamevalid", response_class=HTMLResponse)
def addproject_namevalid(request: Request):
	"""Check if project name is valid."""
	project_name = request.query_params.get("name")
	if not project_name:
		raise HTTPException(status_code=400, detail="Param 'name' required")
	if not is_valid_pathname(project_name):
		raise HTTPException(status_code=400, detail="Invalid project name (no path segments)")
	if _project_in_list(project_name):
		raise HTTPException(status_code=409, detail="Project already exists")
	return HTMLResponse(status_code=200, content=f"Project name '{project_name}' is valid")


@app.get("/addproject", response_class=HTMLResponse)
def addproject_page(request: Request):
	"""Add project form page."""
	pre = PREAMBLE.render(
		title=f"{settings.SITE_NAME} - Add Project",
		site_name=settings.SITE_NAME,
	)
	tpl = env.get_template("addproject.html")
	body = tpl.render(
		site_name=settings.SITE_NAME,
		empty_repo_form_content=Project.form_content(),
		upload_zip_form_content=ProjectZip.form_content(),
	)
	return HTMLResponse(status_code=200, content=f"{pre}{body}{POSTAMBLE}")


@app.post("/addproject", response_class=HTMLResponse)
async def addproject_submit(
	request: Request,
	project_name: Annotated[str, Form()] = "",
	pull_from_remote: Annotated[str, Form()] = "",
	perform_maintenance: Annotated[str, Form()] = "off",
	create_task_board: Annotated[str, Form()] = "off",
	repo_zip: UploadFile | None = _OPTIONAL_REPO_ZIP,
):
	"""
	Create a new project. Allowed only if project name does not exist,
	and valid session in headers / session param (or auth is disabled).
	"""
	if not _request_can_add_project(request):
		raise HTTPException(status_code=401, detail="Authentication required to add projects")

	project_name = (project_name or "").strip()
	if not project_name:
		raise HTTPException(status_code=400, detail="Project name is required")
	if not is_valid_pathname(project_name):
		raise HTTPException(status_code=400, detail="Invalid project name")
	if _project_in_list(project_name):
		raise HTTPException(status_code=409, detail="Project already exists")

	remote_url = (pull_from_remote or "").strip()
	do_maintenance = perform_maintenance.lower() in ("on", "1", "true", "yes")
	do_task_board = create_task_board.lower() in ("on", "1", "true", "yes")

	dest_path = os.path.join(settings.PROJECTROOT, project_name)
	os.makedirs(settings.PROJECTROOT, exist_ok=True)

	try:
		if repo_zip and repo_zip.filename and repo_zip.filename.lower().endswith(".zip"):
			content = await repo_zip.read()
			with ProjectZip(
				path=dest_path,
				zip_content=content,
				create_task_board=do_task_board,
				do_maintenance=do_maintenance,
			):
				pass
		else:
			with Project(
				path=dest_path,
				remote_url=remote_url or None,
				create_task_board=do_task_board,
				do_maintenance=do_maintenance,
			):
				pass

	except pygit2.GitError as e:
		raise HTTPException(status_code=400, detail=f"Git error: {e}") from e
	except HTTPException:
		raise
	except OSError as e:
		raise HTTPException(status_code=500, detail=str(e)) from e

	return RedirectResponse(url=f"/project/{project_name}", status_code=303)


# ---------- Routes (project required) ----------


@app.get("/project/{project:path}/board/", response_class=HTMLResponse)
def project_board(
	project: str,
	board: Annotated[str, Query(alias="b")] = "Tasks",
) -> HTMLResponse:
	"""Board view: columns (dropzones) and task cards."""
	_validate_project(project)
	board_name = board
	project_url = f"/project/{quote(project, safe='/')}"
	board_url = f"{project_url}/board/"
	columns = get_board_tasks_grouped(project, board_name)
	for col in columns:
		for t in col["tasks"]:
			t["task_url"] = f"{board_url}?task={quote(t['ref'], safe='')}"
	pre = PREAMBLE.render(
		title=f"{jinja_escape(project)} - Board",
		site_name=settings.SITE_NAME,
	)
	body = env.get_template("board.html").render(
		project=project,
		project_url=project_url,
		board_name=board_name,
		board_url=board_url,
		columns=columns,
	)
	return HTMLResponse(f"{pre}{body}{POSTAMBLE}")


@app.get("/project/{project:path}/summary-refs")
def project_summary_refs(project: str) -> dict[str, list[dict[str, str]]]:
	_validate_project(project)
	return {"options": summary_ref_options(project)}


@app.get("/project/{project:path}/summary-ref-state")
def project_summary_ref_state(
	project: str,
	ref: Annotated[str | None, Query(alias="ref")] = None,
) -> dict[str, str]:
	_validate_project(project)
	return summary_ref_state(project, ref)


@app.get("/project/{project:path}/subpage/{subpage_name}", response_class=HTMLResponse)
def project_subpage(
	project: str,
	subpage_name: str,
	raw: Annotated[bool, Query()] = False,
) -> HTMLResponse:
	_validate_project(project)
	for subpage in SUBPAGES:
		if subpage.subpage_name() != subpage_name:
			continue
		content = subpage.subpage_html(project)
		if content is None:
			raise HTTPException(status_code=404, detail="No content for subpage")
		content_lc = content.lstrip().lower()
		pre = PREAMBLE.render(
			title=f"{jinja_escape(subpage.link_name(project) or subpage_name)} - {jinja_escape(project)}",
			site_name=settings.SITE_NAME,
		)
		if content_lc.startswith("<!doctype html") or "<html" in content_lc:
			if raw:
				stylesheet_href = "/static/main.css"
				link_tag = f'<link rel="stylesheet" href="{stylesheet_href}">'
				if "<head" in content.lower():
					return HTMLResponse(content.replace("</head>", f"{link_tag}</head>", 1))
				return HTMLResponse(f"{link_tag}{content}")
			project_enc = quote(project, safe="/")
			subpage_enc = quote(subpage_name, safe="")
			iframe_src = f"/project/{project_enc}/subpage/{subpage_enc}?raw=true"
			return HTMLResponse(
				f"{pre}<h1>{jinja_escape(project)}</h1>"
				f'<iframe class="subpage-frame" src="{iframe_src}" title="{jinja_escape(subpage_name)}"></iframe>'
				f"{POSTAMBLE}"
			)
		return HTMLResponse(f"{pre}<h1>{jinja_escape(project)}</h1>{content}{POSTAMBLE}")
	raise HTTPException(status_code=404, detail="Unknown subpage")


@app.get("/project/{project:path}", response_class=HTMLResponse)
def dispatch(
	request: Request,
	project: str,
	a: Annotated[str | None, Query(alias="a")] = None,
	h: Annotated[str | None, Query(alias="h")] = None,
	hb: Annotated[str | None, Query(alias="hb")] = None,
	f: Annotated[str | None, Query(alias="f")] = None,
	fp: Annotated[str | None, Query(alias="fp")] = None,
	page: Annotated[str | None, Query(alias="page")] = None,
	pagecount: Annotated[str | None, Query(alias="pagecount")] = None,
):
	"""
	Dispatch by path: /project/{project} -> summary; /project/{project}/action/... -> action.
	Port of dispatch + run_request path handling.
	"""
	if not project or project == "":
		raise HTTPException(status_code=400, detail="Project needed")
	_validate_project(project)
	action = a
	hash_param = h or hb
	file_name = f
	file_parent = fp
	# If no action, infer: hash only -> object type; project only -> summary
	if not action:
		if hash_param and file_name:
			obj_type = git_get_type(project, f"{hash_param}:{file_name}")
			if not obj_type:
				raise HTTPException(status_code=404, detail="File or directory does not exist")
			action = "tree" if obj_type == "tree" else "blob_plain"
		elif hash_param:
			obj_type = git_get_type(project, hash_param)
			if not obj_type:
				raise HTTPException(status_code=404, detail="Object does not exist")
			action = {
				"commit": "commit",
				"tree": "tree",
				"blob": "blob",
				"tag": "tag",
			}.get(obj_type, "object")
		else:
			action = "summary"
	if action not in ACTIONS:
		raise HTTPException(status_code=400, detail="Unknown action")
	if action in ("opml", "project_list", "project_index"):
		raise HTTPException(status_code=400, detail="Project not needed for this action")
	# Route to handler
	if action == "summary":
		return git_summary(project, extra_rows=_project_subpage_rows(project))
	if action == "tree":
		return git_tree(project, hash_param, file_name)
	if action in ("blob", "blob_plain"):
		return git_blob(project, hash_param, file_name, raw=(action == "blob_plain"))
	if action == "blobdiff":
		return git_blobdiff(project, h, hb, file_name, file_parent)
	if action == "blobpatch":
		return git_blobpatch(project, h, hb, file_name, file_parent)
	if action == "log":
		p, pc = parse_pagination(page, pagecount)
		return git_log(project, hash_param, request, p, pc)
	if action == "shortlog":
		p, pc = parse_pagination(page, pagecount)
		return git_shortlog(project, hash_param, request, p, pc)
	if action == "history":
		p, pc = parse_pagination(page, pagecount)
		return git_history(project, hash_param, file_name, request, p, pc)
	if action == "heads":
		return git_heads(project)
	if action == "tags":
		p, pc = parse_pagination(page, pagecount)
		return git_tags(project, request, p, pc)
	if action == "tag":
		return git_tag(project, hash_param)
	if action == "commit":
		return git_commit(project, hash_param)
	if action == "patch":
		return git_patch(project, h)
	if action == "patches":
		return git_patches(project, h, hb)
	if action == "commitdiff":
		return git_commitdiff(project, hash_param)
	if action == "remotes":
		return git_remotes(project)
	if action == "object":
		return git_object(project, hash_param)
	# Stub others with minimal response
	pre = PREAMBLE.render(title=f"{action} - {project}", site_name=settings.SITE_NAME)
	return HTMLResponse(f"{pre}<p>Action: {jinja_escape(action)}</p><p>Project: {jinja_escape(project)}</p>{POSTAMBLE}")


if __name__ == "__main__":
	import uvicorn

	uvicorn.run(app, host="0.0.0.0", port=8000)