/**
 * Database schema for Codewalkers.
 *
 * Defines the three-level task hierarchy:
 * - Initiative: Top-level project
 * - Phase: Major milestone within initiative
 * - Task: Individual work item (can have parentTaskId for decomposition relationships)
 *
 * Plus a task_dependencies table for task dependency relationships.
 */

import { sqliteTable, text, integer, uniqueIndex, index } from 'drizzle-orm/sqlite-core';
import { relations, type InferInsertModel, type InferSelectModel } from 'drizzle-orm';

// ============================================================================
// INITIATIVES
// ============================================================================

export const initiatives = sqliteTable('initiatives', {
  id: text('id').primaryKey(),
  name: text('name').notNull(),
  status: text('status', { enum: ['active', 'completed', 'archived'] })
    .notNull()
    .default('active'),
  mergeRequiresApproval: integer('merge_requires_approval', { mode: 'boolean' })
    .notNull()
    .default(true),
  branch: text('branch'), // Auto-generated initiative branch (e.g., 'cw/user-auth')
  executionMode: text('execution_mode', { enum: ['yolo', 'review_per_phase'] })
    .notNull()
    .default('review_per_phase'),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
});

export const initiativesRelations = relations(initiatives, ({ many }) => ({
  phases: many(phases),
  pages: many(pages),
  initiativeProjects: many(initiativeProjects),
  tasks: many(tasks),
  changeSets: many(changeSets),
}));

export type Initiative = InferSelectModel<typeof initiatives>;
export type NewInitiative = InferInsertModel<typeof initiatives>;

// ============================================================================
// PHASES
// ============================================================================

export const phases = sqliteTable('phases', {
  id: text('id').primaryKey(),
  initiativeId: text('initiative_id')
    .notNull()
    .references(() => initiatives.id, { onDelete: 'cascade' }),
  name: text('name').notNull(),
  content: text('content'),
  status: text('status', { enum: ['pending', 'approved', 'in_progress', 'completed', 'blocked', 'pending_review'] })
    .notNull()
    .default('pending'),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
});

export const phasesRelations = relations(phases, ({ one, many }) => ({
  initiative: one(initiatives, {
    fields: [phases.initiativeId],
    references: [initiatives.id],
  }),
  tasks: many(tasks),
  // Dependencies: phases this phase depends on
  dependsOn: many(phaseDependencies, { relationName: 'dependentPhase' }),
  // Dependents: phases that depend on this phase
  dependents: many(phaseDependencies, { relationName: 'dependencyPhase' }),
}));

export type Phase = InferSelectModel<typeof phases>;
export type NewPhase = InferInsertModel<typeof phases>;

// ============================================================================
// PHASE DEPENDENCIES
// ============================================================================

export const phaseDependencies = sqliteTable('phase_dependencies', {
  id: text('id').primaryKey(),
  phaseId: text('phase_id')
    .notNull()
    .references(() => phases.id, { onDelete: 'cascade' }),
  dependsOnPhaseId: text('depends_on_phase_id')
    .notNull()
    .references(() => phases.id, { onDelete: 'cascade' }),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
});

export const phaseDependenciesRelations = relations(phaseDependencies, ({ one }) => ({
  phase: one(phases, {
    fields: [phaseDependencies.phaseId],
    references: [phases.id],
    relationName: 'dependentPhase',
  }),
  dependsOnPhase: one(phases, {
    fields: [phaseDependencies.dependsOnPhaseId],
    references: [phases.id],
    relationName: 'dependencyPhase',
  }),
}));

export type PhaseDependency = InferSelectModel<typeof phaseDependencies>;
export type NewPhaseDependency = InferInsertModel<typeof phaseDependencies>;

// ============================================================================
// TASKS
// ============================================================================

/**
 * Task category enum values.
 * Defines what kind of work a task represents.
 */
export const TASK_CATEGORIES = [
  'execute',    // Standard execution task
  'research',   // Research/exploration task
  'discuss',    // Discussion/context gathering
  'plan',       // Plan initiative into phases
  'detail',     // Detail phase into tasks
  'refine',     // Refine/edit content
  'verify',     // Verification task
  'merge',      // Merge task
  'review',     // Review/approval task
] as const;

export type TaskCategory = (typeof TASK_CATEGORIES)[number];

export const tasks = sqliteTable('tasks', {
  id: text('id').primaryKey(),
  // Parent context - at least one should be set
  phaseId: text('phase_id').references(() => phases.id, { onDelete: 'cascade' }),
  initiativeId: text('initiative_id').references(() => initiatives.id, { onDelete: 'cascade' }),
  // Parent task for detail hierarchy (child tasks link to parent detail task)
  parentTaskId: text('parent_task_id').references((): ReturnType<typeof text> => tasks.id, { onDelete: 'cascade' }),
  name: text('name').notNull(),
  description: text('description'),
  type: text('type', {
    enum: ['auto', 'checkpoint:human-verify', 'checkpoint:decision', 'checkpoint:human-action'],
  })
    .notNull()
    .default('auto'),
  category: text('category', {
    enum: TASK_CATEGORIES,
  })
    .notNull()
    .default('execute'),
  priority: text('priority', { enum: ['low', 'medium', 'high'] })
    .notNull()
    .default('medium'),
  status: text('status', {
    enum: ['pending_approval', 'pending', 'in_progress', 'completed', 'blocked'],
  })
    .notNull()
    .default('pending'),
  requiresApproval: integer('requires_approval', { mode: 'boolean' }), // null = inherit from initiative
  order: integer('order').notNull().default(0),
  summary: text('summary'), // Agent result summary — propagated to dependent tasks as context
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
});

export const tasksRelations = relations(tasks, ({ one, many }) => ({
  phase: one(phases, {
    fields: [tasks.phaseId],
    references: [phases.id],
  }),
  initiative: one(initiatives, {
    fields: [tasks.initiativeId],
    references: [initiatives.id],
  }),
  // Parent task (for detail hierarchy - child links to parent detail task)
  parentTask: one(tasks, {
    fields: [tasks.parentTaskId],
    references: [tasks.id],
    relationName: 'parentTask',
  }),
  // Child tasks (tasks created from decomposition of this task)
  childTasks: many(tasks, { relationName: 'parentTask' }),
  // Dependencies: tasks this task depends on
  dependsOn: many(taskDependencies, { relationName: 'dependentTask' }),
  // Dependents: tasks that depend on this task
  dependents: many(taskDependencies, { relationName: 'dependencyTask' }),
}));

export type Task = InferSelectModel<typeof tasks>;
export type NewTask = InferInsertModel<typeof tasks>;

// ============================================================================
// TASK DEPENDENCIES
// ============================================================================

export const taskDependencies = sqliteTable('task_dependencies', {
  id: text('id').primaryKey(),
  taskId: text('task_id')
    .notNull()
    .references(() => tasks.id, { onDelete: 'cascade' }),
  dependsOnTaskId: text('depends_on_task_id')
    .notNull()
    .references(() => tasks.id, { onDelete: 'cascade' }),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
});

export const taskDependenciesRelations = relations(taskDependencies, ({ one }) => ({
  task: one(tasks, {
    fields: [taskDependencies.taskId],
    references: [tasks.id],
    relationName: 'dependentTask',
  }),
  dependsOnTask: one(tasks, {
    fields: [taskDependencies.dependsOnTaskId],
    references: [tasks.id],
    relationName: 'dependencyTask',
  }),
}));

export type TaskDependency = InferSelectModel<typeof taskDependencies>;
export type NewTaskDependency = InferInsertModel<typeof taskDependencies>;

// ============================================================================
// ACCOUNTS
// ============================================================================

export const accounts = sqliteTable('accounts', {
  id: text('id').primaryKey(),
  email: text('email').notNull(),
  provider: text('provider').notNull().default('claude'),
  configJson: text('config_json'),    // .claude.json content (JSON string)
  credentials: text('credentials'),    // .credentials.json content (JSON string)
  isExhausted: integer('is_exhausted', { mode: 'boolean' }).notNull().default(false),
  exhaustedUntil: integer('exhausted_until', { mode: 'timestamp' }),
  lastUsedAt: integer('last_used_at', { mode: 'timestamp' }),
  sortOrder: integer('sort_order').notNull().default(0),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
});

export const accountsRelations = relations(accounts, ({ many }) => ({
  agents: many(agents),
}));

export type Account = InferSelectModel<typeof accounts>;
export type NewAccount = InferInsertModel<typeof accounts>;

// ============================================================================
// AGENTS
// ============================================================================

export const agents = sqliteTable('agents', {
  id: text('id').primaryKey(),
  name: text('name').notNull().unique(), // Human-readable alias (e.g., 'jolly-penguin')
  taskId: text('task_id').references(() => tasks.id, { onDelete: 'set null' }), // Task may be deleted
  initiativeId: text('initiative_id').references(() => initiatives.id, { onDelete: 'set null' }),
  sessionId: text('session_id'), // Claude CLI session ID for resumption (null until first run completes)
  worktreeId: text('worktree_id').notNull(), // Agent alias (deterministic path: agent-workdirs/<alias>/)
  provider: text('provider').notNull().default('claude'),
  accountId: text('account_id').references(() => accounts.id, { onDelete: 'set null' }),
  status: text('status', {
    enum: ['idle', 'running', 'waiting_for_input', 'stopped', 'crashed'],
  })
    .notNull()
    .default('idle'),
  mode: text('mode', { enum: ['execute', 'discuss', 'plan', 'detail', 'refine', 'chat'] })
    .notNull()
    .default('execute'),
  pid: integer('pid'),
  exitCode: integer('exit_code'), // Process exit code for debugging crashes
  outputFilePath: text('output_file_path'),
  result: text('result'),
  pendingQuestions: text('pending_questions'),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
  userDismissedAt: integer('user_dismissed_at', { mode: 'timestamp' }),
});

export const agentsRelations = relations(agents, ({ one, many }) => ({
  task: one(tasks, {
    fields: [agents.taskId],
    references: [tasks.id],
  }),
  initiative: one(initiatives, {
    fields: [agents.initiativeId],
    references: [initiatives.id],
  }),
  account: one(accounts, {
    fields: [agents.accountId],
    references: [accounts.id],
  }),
  changeSets: many(changeSets),
}));

export type Agent = InferSelectModel<typeof agents>;
export type NewAgent = InferInsertModel<typeof agents>;

// ============================================================================
// CHANGE SETS
// ============================================================================

export const changeSets = sqliteTable('change_sets', {
  id: text('id').primaryKey(),
  agentId: text('agent_id')
    .references(() => agents.id, { onDelete: 'set null' }),
  agentName: text('agent_name').notNull(),
  initiativeId: text('initiative_id')
    .notNull()
    .references(() => initiatives.id, { onDelete: 'cascade' }),
  mode: text('mode', { enum: ['plan', 'detail', 'refine', 'chat'] }).notNull(),
  summary: text('summary'),
  status: text('status', { enum: ['applied', 'reverted'] })
    .notNull()
    .default('applied'),
  revertedAt: integer('reverted_at', { mode: 'timestamp' }),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
}, (table) => [
  index('change_sets_initiative_id_idx').on(table.initiativeId),
]);

export const changeSetsRelations = relations(changeSets, ({ one, many }) => ({
  agent: one(agents, {
    fields: [changeSets.agentId],
    references: [agents.id],
  }),
  initiative: one(initiatives, {
    fields: [changeSets.initiativeId],
    references: [initiatives.id],
  }),
  entries: many(changeSetEntries),
}));

export type ChangeSet = InferSelectModel<typeof changeSets>;
export type NewChangeSet = InferInsertModel<typeof changeSets>;

export const changeSetEntries = sqliteTable('change_set_entries', {
  id: text('id').primaryKey(),
  changeSetId: text('change_set_id')
    .notNull()
    .references(() => changeSets.id, { onDelete: 'cascade' }),
  entityType: text('entity_type', { enum: ['page', 'phase', 'task', 'phase_dependency', 'task_dependency'] }).notNull(),
  entityId: text('entity_id').notNull(),
  action: text('action', { enum: ['create', 'update', 'delete'] }).notNull(),
  previousState: text('previous_state'), // JSON snapshot, null for creates
  newState: text('new_state'), // JSON snapshot, null for deletes
  sortOrder: integer('sort_order').notNull().default(0),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
}, (table) => [
  index('change_set_entries_change_set_id_idx').on(table.changeSetId),
]);

export const changeSetEntriesRelations = relations(changeSetEntries, ({ one }) => ({
  changeSet: one(changeSets, {
    fields: [changeSetEntries.changeSetId],
    references: [changeSets.id],
  }),
}));

export type ChangeSetEntry = InferSelectModel<typeof changeSetEntries>;
export type NewChangeSetEntry = InferInsertModel<typeof changeSetEntries>;

// ============================================================================
// MESSAGES
// ============================================================================

export const messages = sqliteTable('messages', {
  id: text('id').primaryKey(),
  senderType: text('sender_type', { enum: ['agent', 'user'] }).notNull(),
  senderId: text('sender_id').references(() => agents.id, { onDelete: 'set null' }), // Agent ID if senderType='agent', null for user
  recipientType: text('recipient_type', { enum: ['agent', 'user'] }).notNull(),
  recipientId: text('recipient_id').references(() => agents.id, { onDelete: 'set null' }), // Agent ID if recipientType='agent', null for user
  type: text('type', { enum: ['question', 'info', 'error', 'response'] })
    .notNull()
    .default('info'),
  content: text('content').notNull(),
  requiresResponse: integer('requires_response', { mode: 'boolean' })
    .notNull()
    .default(false),
  status: text('status', { enum: ['pending', 'read', 'responded'] })
    .notNull()
    .default('pending'),
  parentMessageId: text('parent_message_id').references((): ReturnType<typeof text> => messages.id, { onDelete: 'set null' }), // Links response to original question
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
});

export const messagesRelations = relations(messages, ({ one, many }) => ({
  // Sender agent (optional - null for user senders)
  senderAgent: one(agents, {
    fields: [messages.senderId],
    references: [agents.id],
    relationName: 'senderAgent',
  }),
  // Recipient agent (optional - null for user recipients)
  recipientAgent: one(agents, {
    fields: [messages.recipientId],
    references: [agents.id],
    relationName: 'recipientAgent',
  }),
  // Parent message (for threading responses)
  parentMessage: one(messages, {
    fields: [messages.parentMessageId],
    references: [messages.id],
    relationName: 'parentMessage',
  }),
  // Child messages (replies to this message)
  childMessages: many(messages, { relationName: 'parentMessage' }),
}));

export type Message = InferSelectModel<typeof messages>;
export type NewMessage = InferInsertModel<typeof messages>;

// ============================================================================
// PAGES
// ============================================================================

export const pages = sqliteTable('pages', {
  id: text('id').primaryKey(),
  initiativeId: text('initiative_id')
    .notNull()
    .references(() => initiatives.id, { onDelete: 'cascade' }),
  parentPageId: text('parent_page_id').references((): ReturnType<typeof text> => pages.id, { onDelete: 'cascade' }),
  title: text('title').notNull(),
  content: text('content'), // JSON string from Tiptap
  sortOrder: integer('sort_order').notNull().default(0),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
});

export const pagesRelations = relations(pages, ({ one, many }) => ({
  initiative: one(initiatives, {
    fields: [pages.initiativeId],
    references: [initiatives.id],
  }),
  parentPage: one(pages, {
    fields: [pages.parentPageId],
    references: [pages.id],
    relationName: 'parentPage',
  }),
  childPages: many(pages, { relationName: 'parentPage' }),
}));

export type Page = InferSelectModel<typeof pages>;
export type NewPage = InferInsertModel<typeof pages>;

// ============================================================================
// PROJECTS
// ============================================================================

export const projects = sqliteTable('projects', {
  id: text('id').primaryKey(),
  name: text('name').notNull().unique(),
  url: text('url').notNull().unique(),
  defaultBranch: text('default_branch').notNull().default('main'),
  lastFetchedAt: integer('last_fetched_at', { mode: 'timestamp' }),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
});

export const projectsRelations = relations(projects, ({ many }) => ({
  initiativeProjects: many(initiativeProjects),
}));

export type Project = InferSelectModel<typeof projects>;
export type NewProject = InferInsertModel<typeof projects>;

// ============================================================================
// INITIATIVE PROJECTS (junction)
// ============================================================================

export const initiativeProjects = sqliteTable('initiative_projects', {
  id: text('id').primaryKey(),
  initiativeId: text('initiative_id')
    .notNull()
    .references(() => initiatives.id, { onDelete: 'cascade' }),
  projectId: text('project_id')
    .notNull()
    .references(() => projects.id, { onDelete: 'cascade' }),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
}, (table) => [
  uniqueIndex('initiative_project_unique').on(table.initiativeId, table.projectId),
]);

export const initiativeProjectsRelations = relations(initiativeProjects, ({ one }) => ({
  initiative: one(initiatives, {
    fields: [initiativeProjects.initiativeId],
    references: [initiatives.id],
  }),
  project: one(projects, {
    fields: [initiativeProjects.projectId],
    references: [projects.id],
  }),
}));

export type InitiativeProject = InferSelectModel<typeof initiativeProjects>;
export type NewInitiativeProject = InferInsertModel<typeof initiativeProjects>;

// ============================================================================
// AGENT LOG CHUNKS
// ============================================================================

export const agentLogChunks = sqliteTable('agent_log_chunks', {
  id: text('id').primaryKey(),
  agentId: text('agent_id').notNull(),            // NO FK — survives agent deletion
  agentName: text('agent_name').notNull(),         // Snapshot for display after deletion
  sessionNumber: integer('session_number').notNull().default(1),
  content: text('content').notNull(),              // Raw JSONL chunk from file
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
}, (table) => [
  index('agent_log_chunks_agent_id_idx').on(table.agentId),
]);

export type AgentLogChunk = InferSelectModel<typeof agentLogChunks>;
export type NewAgentLogChunk = InferInsertModel<typeof agentLogChunks>;

// ============================================================================
// CONVERSATIONS (inter-agent communication)
// ============================================================================

export const conversations = sqliteTable('conversations', {
  id: text('id').primaryKey(),
  fromAgentId: text('from_agent_id').notNull().references(() => agents.id, { onDelete: 'cascade' }),
  toAgentId: text('to_agent_id').notNull().references(() => agents.id, { onDelete: 'cascade' }),
  initiativeId: text('initiative_id').references(() => initiatives.id, { onDelete: 'set null' }),
  phaseId: text('phase_id').references(() => phases.id, { onDelete: 'set null' }),
  taskId: text('task_id').references(() => tasks.id, { onDelete: 'set null' }),
  question: text('question').notNull(),
  answer: text('answer'),
  status: text('status', { enum: ['pending', 'answered'] }).notNull().default('pending'),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
}, (table) => [
  index('conversations_to_agent_status_idx').on(table.toAgentId, table.status),
  index('conversations_from_agent_idx').on(table.fromAgentId),
]);

export type Conversation = InferSelectModel<typeof conversations>;
export type NewConversation = InferInsertModel<typeof conversations>;

// ============================================================================
// CHAT SESSIONS
// ============================================================================

export const chatSessions = sqliteTable('chat_sessions', {
  id: text('id').primaryKey(),
  targetType: text('target_type', { enum: ['phase', 'task'] }).notNull(),
  targetId: text('target_id').notNull(),
  initiativeId: text('initiative_id')
    .notNull()
    .references(() => initiatives.id, { onDelete: 'cascade' }),
  agentId: text('agent_id').references(() => agents.id, { onDelete: 'set null' }),
  status: text('status', { enum: ['active', 'closed'] })
    .notNull()
    .default('active'),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
}, (table) => [
  index('chat_sessions_target_idx').on(table.targetType, table.targetId),
  index('chat_sessions_initiative_id_idx').on(table.initiativeId),
]);

export const chatSessionsRelations = relations(chatSessions, ({ one, many }) => ({
  initiative: one(initiatives, {
    fields: [chatSessions.initiativeId],
    references: [initiatives.id],
  }),
  agent: one(agents, {
    fields: [chatSessions.agentId],
    references: [agents.id],
  }),
  messages: many(chatMessages),
}));

export type ChatSession = InferSelectModel<typeof chatSessions>;
export type NewChatSession = InferInsertModel<typeof chatSessions>;

// ============================================================================
// CHAT MESSAGES
// ============================================================================

export const chatMessages = sqliteTable('chat_messages', {
  id: text('id').primaryKey(),
  chatSessionId: text('chat_session_id')
    .notNull()
    .references(() => chatSessions.id, { onDelete: 'cascade' }),
  role: text('role', { enum: ['user', 'assistant', 'system'] }).notNull(),
  content: text('content').notNull(),
  changeSetId: text('change_set_id').references(() => changeSets.id, { onDelete: 'set null' }),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
}, (table) => [
  index('chat_messages_session_id_idx').on(table.chatSessionId),
]);

export const chatMessagesRelations = relations(chatMessages, ({ one }) => ({
  chatSession: one(chatSessions, {
    fields: [chatMessages.chatSessionId],
    references: [chatSessions.id],
  }),
  changeSet: one(changeSets, {
    fields: [chatMessages.changeSetId],
    references: [changeSets.id],
  }),
}));

export type ChatMessage = InferSelectModel<typeof chatMessages>;
export type NewChatMessage = InferInsertModel<typeof chatMessages>;

// ============================================================================
// REVIEW COMMENTS
// ============================================================================

export const reviewComments = sqliteTable('review_comments', {
  id: text('id').primaryKey(),
  phaseId: text('phase_id')
    .notNull()
    .references(() => phases.id, { onDelete: 'cascade' }),
  filePath: text('file_path').notNull(),
  lineNumber: integer('line_number').notNull(),
  lineType: text('line_type', { enum: ['added', 'removed', 'context'] }).notNull(),
  body: text('body').notNull(),
  author: text('author').notNull().default('you'),
  resolved: integer('resolved', { mode: 'boolean' }).notNull().default(false),
  createdAt: integer('created_at', { mode: 'timestamp' }).notNull(),
  updatedAt: integer('updated_at', { mode: 'timestamp' }).notNull(),
}, (table) => [
  index('review_comments_phase_id_idx').on(table.phaseId),
]);

export type ReviewComment = InferSelectModel<typeof reviewComments>;
export type NewReviewComment = InferInsertModel<typeof reviewComments>;