from __future__ import annotations

from collections import Counter

from services.data_migration.entities import ReportContext, ResourceIdMapping, ResourceReportItem


class MigrationReportService:
    """Render structured migration resource results into CLI-friendly summary lines."""

    def render(self, items: list[ResourceReportItem], *, context: ReportContext | None = None) -> list[str]:
        counts = Counter((item.resource_type.value, item.status) for item in items)
        lines = self._render_context(context)
        lines.extend(
            [f"{resource_type} {status}: {count}" for (resource_type, status), count in sorted(counts.items())]
        )
        actionable_items = [
            item for item in items if item.status in {"dependency-only", "skipped", "unresolved"} and item.message
        ]
        for item in actionable_items:
            lines.append(self._render_actionable_detail(item))
        return lines

    def _render_context(self, context: ReportContext | None) -> list[str]:
        if context is None:
            return []
        lines: list[str] = []
        if context.output_path:
            lines.append(f"output: {context.output_path}")
        if context.source_scope:
            lines.append(f"source scope: {context.source_scope}")
        if context.selected_app_count is not None:
            lines.append(f"selected apps: {context.selected_app_count}")
        if context.include_secrets is not None:
            lines.append(f"include secrets: {str(context.include_secrets).lower()}")
        if context.target_tenant:
            lines.append(f"target tenant: {context.target_tenant}")
        if context.operator_email:
            lines.append(f"operator: {context.operator_email}")
        if context.app_api_tokens_created or context.app_api_tokens_reused:
            lines.append(
                f"app api tokens: {context.app_api_tokens_created} created, {context.app_api_tokens_reused} reused"
            )
        if context.id_mappings:
            lines.append(f"resource references resolved: {len(context.id_mappings)}")
            if context.id_mapping_details:
                lines.extend(
                    self._render_id_mapping_detail(item)
                    for item in sorted(
                        context.id_mapping_details,
                        key=lambda item: (item.resource_type.value, item.name or "", item.source_id),
                    )
                )
            else:
                lines.extend(
                    f"- {source_id} -> {target_id}" for source_id, target_id in sorted(context.id_mappings.items())
                )
        elif context.id_mapping_count:
            lines.append(f"resource references resolved: {context.id_mapping_count}")
        return lines

    def _render_id_mapping_detail(self, item: ResourceIdMapping) -> str:
        label = item.resource_type.value
        if item.name:
            label = f"{label} {item.name}"
        return f"- {label}: {item.source_id} -> {item.target_id}"

    def _render_actionable_detail(self, item: ResourceReportItem) -> str:
        if item.resource_type.value == "dependency" and item.name and self._has_dependency_type_prefix(item.name):
            if item.identifier and item.identifier not in item.name:
                return f"dependency {item.name}: {item.identifier}: {item.message}"
            return f"dependency {item.name}: {item.message}"
        return f"{item.resource_type.value} {item.identifier}: {item.message}"

    def _has_dependency_type_prefix(self, name: str) -> bool:
        return name.startswith(("workflow ", "api_tool ", "workflow_tool ", "mcp_tool ", "builtin_or_plugin_tool "))