"""Initiative (Vorhaben) API — AP0.5."""

from __future__ import annotations

from datetime import datetime
from typing import Literal, Optional

from capabilities import require_capability
from data_layer import initiative_snapshot as dl_initiative_snapshot
from fastapi import APIRouter, Depends, HTTPException
from pydantic import BaseModel, Field
from services import actions as action_service
from services import backlog as backlog_service
from services import blockers as blocker_service
from services import decisions as decision_service
from services import evidence as evidence_service
from services import initiatives as initiative_service
from services import milestones as milestone_service
from services import recurring as recurring_service
from services import reviews as review_service
from tenant_context import TenantContext

router = APIRouter(prefix="/api/initiatives", tags=["initiatives"])


class InitiativeCreateRequest(BaseModel):
    title: str = Field(min_length=1, max_length=255)
    goal: str = ""
    status: Literal["active", "paused", "completed", "archived"] = "active"
    priority: Literal["low", "normal", "high"] = "normal"
    owner_actor_id: Optional[str] = None


class InitiativeUpdateRequest(BaseModel):
    title: Optional[str] = Field(default=None, min_length=1, max_length=255)
    goal: Optional[str] = None
    status: Optional[Literal["active", "paused", "completed", "archived"]] = None
    priority: Optional[Literal["low", "normal", "high"]] = None
    owner_actor_id: Optional[str] = None


class ActionCreateRequest(BaseModel):
    title: str = Field(min_length=1, max_length=255)
    description: str = ""
    status: Literal[
        "open", "ready", "in_progress", "blocked", "review_required", "done", "discarded"
    ] = "open"
    priority: Literal["low", "normal", "high"] = "normal"
    due_at: Optional[str] = None
    assigned_actor_ids: list[str] = Field(default_factory=list)


class BlockerCreateRequest(BaseModel):
    title: str = Field(min_length=1, max_length=255)
    description: str = ""
    status: Literal["open", "in_progress", "resolved", "accepted_risk", "dismissed"] = "open"
    action_id: Optional[str] = None
    set_action_blocked: bool = False


class BacklogCreateRequest(BaseModel):
    title: str = Field(min_length=1, max_length=255)
    description: str = ""
    status: Literal["new", "triaged", "accepted", "rejected"] = "new"
    priority: Literal["low", "normal", "high"] = "normal"


class MilestoneCreateRequest(BaseModel):
    title: str = Field(min_length=1, max_length=255)
    goal_description: str = ""
    status: Literal["planned", "active", "at_risk", "reached", "moved", "discarded"] = "planned"
    target_date: Optional[str] = None


class EvidenceCreateRequest(BaseModel):
    title: str = Field(min_length=1, max_length=255)
    description: str = ""
    status: Literal["submitted", "accepted", "rejected"] = "submitted"
    action_id: Optional[str] = None
    milestone_id: Optional[str] = None


class DecisionCreateRequest(BaseModel):
    title: str = Field(min_length=1, max_length=255)
    description: str = ""
    status: Literal["proposed", "decided", "superseded"] = "proposed"
    outcome: str = ""


class ReviewCreateRequest(BaseModel):
    title: str = Field(min_length=1, max_length=255)
    summary: str = ""
    status: Literal["planned", "completed", "skipped"] = "planned"
    due_at: Optional[str] = None
    action_id: Optional[str] = None
    milestone_id: Optional[str] = None


class RecurringCreateRequest(BaseModel):
    title: str = Field(min_length=1, max_length=255)
    description: str = ""
    status: Literal["active", "paused", "ended"] = "active"
    interval_days: Optional[int] = Field(default=None, gt=0)
    next_due_at: Optional[str] = None


def _parse_optional_datetime(value: Optional[str], field_name: str) -> Optional[datetime]:
    if not value:
        return None
    try:
        return datetime.fromisoformat(value.replace("Z", "+00:00"))
    except ValueError as exc:
        raise HTTPException(status_code=400, detail=f"Ungültiges {field_name}") from exc


@router.get("")
def list_initiatives(
    ctx: TenantContext = Depends(require_capability("kairo.initiative.read")),
):
    return initiative_service.list_initiatives(tenant_id=ctx.tenant_id)


@router.post("", status_code=201)
def create_initiative(
    body: InitiativeCreateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.initiative.manage")),
):
    owner_actor_id = body.owner_actor_id or ctx.actor_id
    if not owner_actor_id:
        raise HTTPException(status_code=400, detail="Kein Actor im TenantContext")
    try:
        return initiative_service.create_initiative(
            tenant_id=ctx.tenant_id,
            title=body.title,
            goal=body.goal,
            status=body.status,
            priority=body.priority,
            owner_actor_id=owner_actor_id,
            user_id=ctx.user_id,
        )
    except ValueError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc


@router.get("/{initiative_id}")
def get_initiative(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.initiative.read")),
):
    item = initiative_service.get_initiative(
        tenant_id=ctx.tenant_id, initiative_id=initiative_id
    )
    if not item:
        raise HTTPException(status_code=404, detail="Vorhaben nicht gefunden")
    return item


@router.get("/{initiative_id}/steering-snapshot")
def get_initiative_steering_snapshot(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.initiative.read")),
):
    snapshot = dl_initiative_snapshot.get_initiative_steering_snapshot(
        ctx, initiative_id=initiative_id
    )
    if not snapshot:
        raise HTTPException(status_code=404, detail="Vorhaben nicht gefunden")
    return snapshot


@router.patch("/{initiative_id}")
def update_initiative(
    initiative_id: str,
    body: InitiativeUpdateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.initiative.manage")),
):
    try:
        item = initiative_service.update_initiative(
            tenant_id=ctx.tenant_id,
            initiative_id=initiative_id,
            user_id=ctx.user_id,
            title=body.title,
            goal=body.goal,
            status=body.status,
            priority=body.priority,
            owner_actor_id=body.owner_actor_id,
        )
    except ValueError as exc:
        raise HTTPException(status_code=400, detail=str(exc)) from exc
    if not item:
        raise HTTPException(status_code=404, detail="Vorhaben nicht gefunden")
    return item


@router.delete("/{initiative_id}", status_code=204)
def delete_initiative(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.initiative.manage")),
):
    if not initiative_service.delete_initiative(
        tenant_id=ctx.tenant_id,
        initiative_id=initiative_id,
        user_id=ctx.user_id,
    ):
        raise HTTPException(status_code=404, detail="Vorhaben nicht gefunden")


@router.get("/{initiative_id}/actions")
def list_initiative_actions(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.action.read")),
):
    if not initiative_service.get_initiative(
        tenant_id=ctx.tenant_id, initiative_id=initiative_id
    ):
        raise HTTPException(status_code=404, detail="Vorhaben nicht gefunden")
    return action_service.list_actions_for_initiative(
        tenant_id=ctx.tenant_id, initiative_id=initiative_id
    )


@router.post("/{initiative_id}/actions", status_code=201)
def create_initiative_action(
    initiative_id: str,
    body: ActionCreateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.action.manage")),
):
    try:
        due_at = _parse_optional_datetime(body.due_at, "due_at")
        return action_service.create_action(
            tenant_id=ctx.tenant_id,
            initiative_id=initiative_id,
            title=body.title,
            description=body.description,
            status=body.status,
            priority=body.priority,
            due_at=due_at,
            assigned_actor_ids=body.assigned_actor_ids,
            user_id=ctx.user_id,
        )
    except ValueError as exc:
        detail = str(exc)
        if detail == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=detail) from exc
        raise HTTPException(status_code=400, detail=detail) from exc


@router.get("/{initiative_id}/blockers")
def list_initiative_blockers(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.blocker.read")),
):
    try:
        return blocker_service.list_blockers_for_initiative(
            tenant_id=ctx.tenant_id, initiative_id=initiative_id
        )
    except ValueError as exc:
        if str(exc) == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=str(exc)) from exc
        raise HTTPException(status_code=400, detail=str(exc)) from exc


@router.post("/{initiative_id}/blockers", status_code=201)
def create_initiative_blocker(
    initiative_id: str,
    body: BlockerCreateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.blocker.manage")),
):
    try:
        return blocker_service.create_blocker(
            tenant_id=ctx.tenant_id,
            initiative_id=initiative_id,
            title=body.title,
            description=body.description,
            status=body.status,
            action_id=body.action_id,
            reported_by_actor_id=ctx.actor_id,
            user_id=ctx.user_id,
            set_action_blocked=body.set_action_blocked,
        )
    except ValueError as exc:
        detail = str(exc)
        if detail == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=detail) from exc
        raise HTTPException(status_code=400, detail=detail) from exc


@router.get("/{initiative_id}/backlog")
def list_initiative_backlog(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.backlog.read")),
):
    try:
        return backlog_service.list_backlog_for_initiative(
            tenant_id=ctx.tenant_id, initiative_id=initiative_id
        )
    except ValueError as exc:
        if str(exc) == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=str(exc)) from exc
        raise HTTPException(status_code=400, detail=str(exc)) from exc


@router.post("/{initiative_id}/backlog", status_code=201)
def create_initiative_backlog_item(
    initiative_id: str,
    body: BacklogCreateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.backlog.manage")),
):
    try:
        return backlog_service.create_backlog_item(
            tenant_id=ctx.tenant_id,
            initiative_id=initiative_id,
            title=body.title,
            description=body.description,
            status=body.status,
            priority=body.priority,
            user_id=ctx.user_id,
        )
    except ValueError as exc:
        detail = str(exc)
        if detail == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=detail) from exc
        raise HTTPException(status_code=400, detail=detail) from exc


@router.get("/{initiative_id}/milestones")
def list_initiative_milestones(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.milestone.read")),
):
    try:
        return milestone_service.list_milestones_for_initiative(
            tenant_id=ctx.tenant_id, initiative_id=initiative_id
        )
    except ValueError as exc:
        if str(exc) == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=str(exc)) from exc
        raise HTTPException(status_code=400, detail=str(exc)) from exc


@router.post("/{initiative_id}/milestones", status_code=201)
def create_initiative_milestone(
    initiative_id: str,
    body: MilestoneCreateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.milestone.manage")),
):
    from datetime import date as date_type

    target_date = None
    if body.target_date:
        try:
            target_date = date_type.fromisoformat(body.target_date)
        except ValueError as exc:
            raise HTTPException(status_code=400, detail="Ungültiges target_date") from exc
    try:
        return milestone_service.create_milestone(
            tenant_id=ctx.tenant_id,
            initiative_id=initiative_id,
            title=body.title,
            goal_description=body.goal_description,
            status=body.status,
            target_date=target_date,
            user_id=ctx.user_id,
        )
    except ValueError as exc:
        detail = str(exc)
        if detail == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=detail) from exc
        raise HTTPException(status_code=400, detail=detail) from exc


@router.get("/{initiative_id}/evidence")
def list_initiative_evidence(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.evidence.read")),
):
    try:
        return evidence_service.list_evidence_for_initiative(
            tenant_id=ctx.tenant_id, initiative_id=initiative_id
        )
    except ValueError as exc:
        if str(exc) == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=str(exc)) from exc
        raise HTTPException(status_code=400, detail=str(exc)) from exc


@router.post("/{initiative_id}/evidence", status_code=201)
def create_initiative_evidence(
    initiative_id: str,
    body: EvidenceCreateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.evidence.manage")),
):
    try:
        return evidence_service.create_evidence(
            tenant_id=ctx.tenant_id,
            initiative_id=initiative_id,
            title=body.title,
            description=body.description,
            status=body.status,
            action_id=body.action_id,
            milestone_id=body.milestone_id,
            submitted_by_actor_id=ctx.actor_id,
            user_id=ctx.user_id,
        )
    except ValueError as exc:
        detail = str(exc)
        if detail == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=detail) from exc
        raise HTTPException(status_code=400, detail=detail) from exc


@router.get("/{initiative_id}/decisions")
def list_initiative_decisions(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.decision.read")),
):
    try:
        return decision_service.list_decisions_for_initiative(
            tenant_id=ctx.tenant_id, initiative_id=initiative_id
        )
    except ValueError as exc:
        if str(exc) == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=str(exc)) from exc
        raise HTTPException(status_code=400, detail=str(exc)) from exc


@router.post("/{initiative_id}/decisions", status_code=201)
def create_initiative_decision(
    initiative_id: str,
    body: DecisionCreateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.decision.manage")),
):
    try:
        return decision_service.create_decision(
            tenant_id=ctx.tenant_id,
            initiative_id=initiative_id,
            title=body.title,
            description=body.description,
            status=body.status,
            outcome=body.outcome,
            decided_by_actor_id=ctx.actor_id if body.status == "decided" else None,
            user_id=ctx.user_id,
        )
    except ValueError as exc:
        detail = str(exc)
        if detail == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=detail) from exc
        raise HTTPException(status_code=400, detail=detail) from exc


@router.get("/{initiative_id}/reviews")
def list_initiative_reviews(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.review.read")),
):
    try:
        return review_service.list_reviews_for_initiative(
            tenant_id=ctx.tenant_id, initiative_id=initiative_id
        )
    except ValueError as exc:
        if str(exc) == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=str(exc)) from exc
        raise HTTPException(status_code=400, detail=str(exc)) from exc


@router.post("/{initiative_id}/reviews", status_code=201)
def create_initiative_review(
    initiative_id: str,
    body: ReviewCreateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.review.manage")),
):
    due_at = _parse_optional_datetime(body.due_at, "due_at")
    try:
        return review_service.create_review(
            tenant_id=ctx.tenant_id,
            initiative_id=initiative_id,
            title=body.title,
            summary=body.summary,
            status=body.status,
            due_at=due_at,
            action_id=body.action_id,
            milestone_id=body.milestone_id,
            reviewed_by_actor_id=ctx.actor_id,
            user_id=ctx.user_id,
        )
    except ValueError as exc:
        detail = str(exc)
        if detail == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=detail) from exc
        raise HTTPException(status_code=400, detail=detail) from exc


@router.get("/{initiative_id}/recurring")
def list_initiative_recurring(
    initiative_id: str,
    ctx: TenantContext = Depends(require_capability("kairo.recurring.read")),
):
    try:
        return recurring_service.list_recurring_for_initiative(
            tenant_id=ctx.tenant_id, initiative_id=initiative_id
        )
    except ValueError as exc:
        if str(exc) == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=str(exc)) from exc
        raise HTTPException(status_code=400, detail=str(exc)) from exc


@router.post("/{initiative_id}/recurring", status_code=201)
def create_initiative_recurring(
    initiative_id: str,
    body: RecurringCreateRequest,
    ctx: TenantContext = Depends(require_capability("kairo.recurring.manage")),
):
    next_due_at = _parse_optional_datetime(body.next_due_at, "next_due_at")
    try:
        return recurring_service.create_recurring_element(
            tenant_id=ctx.tenant_id,
            initiative_id=initiative_id,
            title=body.title,
            description=body.description,
            status=body.status,
            interval_days=body.interval_days,
            next_due_at=next_due_at,
            user_id=ctx.user_id,
        )
    except ValueError as exc:
        detail = str(exc)
        if detail == "Initiative nicht gefunden":
            raise HTTPException(status_code=404, detail=detail) from exc
        raise HTTPException(status_code=400, detail=detail) from exc