-- Legacy Tasks Tables extracted from consolidated

-- Core tasks table
CREATE TABLE IF NOT EXISTS tasks (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    title TEXT NOT NULL,
    description TEXT,
    status TEXT NOT NULL DEFAULT 'todo',
    priority TEXT NOT NULL DEFAULT 'medium',
    assignee_id UUID REFERENCES users(id) ON DELETE SET NULL,
    reporter_id UUID REFERENCES users(id) ON DELETE SET NULL,
    project_id UUID,
    due_date TIMESTAMPTZ,
    tags TEXT[] DEFAULT '{}',
    dependencies UUID[] DEFAULT '{}',
    estimated_hours FLOAT8,
    actual_hours FLOAT8,
    progress INT DEFAULT 0,
    created_at TIMESTAMPTZ DEFAULT NOW(),
    updated_at TIMESTAMPTZ DEFAULT NOW(),
    completed_at TIMESTAMPTZ,
    CONSTRAINT check_task_status CHECK (status IN ('todo', 'in_progress', 'review', 'blocked', 'on_hold', 'done', 'completed', 'cancelled')),
    CONSTRAINT check_task_priority CHECK (priority IN ('low', 'medium', 'high', 'urgent'))
);

CREATE INDEX IF NOT EXISTS idx_tasks_assignee ON tasks(assignee_id);
CREATE INDEX IF NOT EXISTS idx_tasks_reporter ON tasks(reporter_id);
CREATE INDEX IF NOT EXISTS idx_tasks_project ON tasks(project_id);
CREATE INDEX IF NOT EXISTS idx_tasks_status ON tasks(status);
CREATE INDEX IF NOT EXISTS idx_tasks_due_date ON tasks(due_date);
CREATE INDEX IF NOT EXISTS idx_tasks_created ON tasks(created_at);

-- Task dependencies
CREATE TABLE IF NOT EXISTS task_dependencies (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    task_id UUID NOT NULL REFERENCES tasks(id) ON DELETE CASCADE,
    depends_on_task_id UUID NOT NULL REFERENCES tasks(id) ON DELETE CASCADE,
    dependency_type VARCHAR(20) DEFAULT 'finish_to_start',
    lag_days INTEGER DEFAULT 0,
    created_at TIMESTAMPTZ DEFAULT NOW(),
    CONSTRAINT check_dependency_type CHECK (dependency_type IN ('finish_to_start', 'start_to_start', 'finish_to_finish', 'start_to_finish')),
    CONSTRAINT unique_task_dependency UNIQUE (task_id, depends_on_task_id)
);

CREATE INDEX IF NOT EXISTS idx_task_dependencies_task ON task_dependencies(task_id);
CREATE INDEX IF NOT EXISTS idx_task_dependencies_depends ON task_dependencies(depends_on_task_id);

-- Task time tracking
CREATE TABLE IF NOT EXISTS task_time_entries (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    task_id UUID NOT NULL REFERENCES tasks(id) ON DELETE CASCADE,
    user_id UUID NOT NULL REFERENCES users(id) ON DELETE CASCADE,
    description TEXT,
    started_at TIMESTAMPTZ NOT NULL,
    ended_at TIMESTAMPTZ,
    duration_minutes INTEGER,
    is_billable BOOLEAN DEFAULT false,
    created_at TIMESTAMPTZ DEFAULT NOW()
);

CREATE INDEX IF NOT EXISTS idx_task_time_task ON task_time_entries(task_id);
CREATE INDEX IF NOT EXISTS idx_task_time_user ON task_time_entries(user_id, started_at);

-- Task recurring rules
CREATE TABLE IF NOT EXISTS task_recurrence (
    id UUID PRIMARY KEY DEFAULT gen_random_uuid(),
    task_template_id UUID NOT NULL REFERENCES tasks(id) ON DELETE CASCADE,
    recurrence_pattern VARCHAR(20) NOT NULL,
    interval_value INTEGER DEFAULT 1,
    days_of_week_json TEXT,
    day_of_month INTEGER,
    month_of_year INTEGER,
    end_date TIMESTAMPTZ,
    occurrence_count INTEGER,
    next_occurrence TIMESTAMPTZ,
    is_active BOOLEAN DEFAULT true,
    created_at TIMESTAMPTZ DEFAULT NOW(),
    CONSTRAINT check_recurrence CHECK (recurrence_pattern IN ('daily', 'weekly', 'monthly', 'yearly', 'custom'))
);

CREATE INDEX IF NOT EXISTS idx_task_recurrence_next ON task_recurrence(next_occurrence) WHERE is_active = true;